the space science enterprise - NASA40 years, space probes and space observatories have played a cen-tral role in this fascinating process. Today, NASA addresses these four profound

t h e s p a c e s c i e n c e e n t e r p r i s en o v e m b e r 2 0 0 0

Cassiopeia A: The 320-year-old remnant of a massive star that exploded. Locatedin the constellation Cassiopeia, it is 10 light years across and 10,000 light yearsfrom Earth. This X-ray image of Cassiopeia A is the official first light image of theChandra X-ray Observatory. The 5,000-second image was made with the AdvancedCCD Imaging Spectrometer (ACIS). Two shock waves are visible: a fast outer shockand a slower inner shock. The inner shock wave is believed to be due to thecollision of the ejecta from the supernova explosion with a circumstellar shell ofmaterial, heating it to a temperature of ten million degrees. The outer shock waveis analogous to a tremendous sonic boom resulting from this collision. The brightobject near the center may be the long sought neutron star or black hole thatremained after the explosion that produced Cassiopeia A. (Credit: NASA/CXC/SAO)

Dedicated to the memories of

Herbert Friedman and John A. Simpson

– Pioneers of Space Science–

National Aeronautics andSpace Administration

the space science enterprise

strategic plan

NP-2000-08-258-HQ

n o v e m b e r 2 0 0 0

November 2000

Dear Colleagues and Friends of Space Science,

It is a pleasure to present our new Space Science Strategic Plan. It represents contributions by hundreds ofmembers of the space science community, including researchers, technologists, and educators, working withstaff at NASA, over a period of nearly two years.

Our time is an exciting one for space science. Dramatic advances in cosmology, planetary research, and solar-terrestrial science form a backdrop for this ambitious plan. Our program boldly addresses the most funda-mental questions that science can ask: how the universe began and is changing, what are the past and future ofhumanity, and whether we are alone. In taking up these questions, researchers and the general public—for weare all seekers in this quest—will draw upon all areas of science and the technical arts. Our Plan outlines howwe will communicate our findings to interested young people and adults.

The program that you will read about in this Plan includes forefront research and technology development onthe ground as well as development and operation of the most complex spacecraft conceived. The proposed flightprogram is a balanced portfolio of small missions and larger spacecraft. Our goal is to obtain the best science atthe lowest cost, taking advantage of the most advanced technology that can meet our standards for expected mis-sion success. In driving hard to achieve this goal, we experienced some very disappointing failures in 1999. ButNASA, as an R&D agency, makes progress by learning also from mistakes, and we have learned from these.

Over the coming years, I invite you to watch as our plans come to fruition. This is your program, and we aremanaging it for you to answer the profoundest questions that we all share. I fully expect exciting surprises as ourvoyage of discovery continues to expand our knowledge about the history and future of our universe and ofhumankind within it.

Edward J. WeilerAssociate Administrator for Space Science

the space science enterprise seeks tothe space science enterprise seeks to

discover

• how the universe began and evolved

• how we got here

• where we are going

• and whether we are alone

discover

• how the universe began and evolved

• how we got here

• where we are going

• and whether we are alone

| the space science enterprise strategic plan

Letter from the Associate Administrator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Section I-1: Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Section I-2: Goals and Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

Section I-3: The Role of Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18

Section I-4: The Role of Education and Public Outreach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

Section II-1: Recent Accomplishments and Current Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28

Section II-2: Principles and Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44

Section II-3: Flight Program: 2003 and Beyond . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50

4

t ab l e o f con ten t s

our

our program

our goals

Section II-4: Technology Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76

Section II-5: Research and Data Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86

Section II-6: Education and Public Outreach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94

Section II-7: Partnerships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98

Section II-8: A Vision of the Future . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104

Section A-1: Science Goals and Missions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110

Section A-2: Glossary of Missions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114

Section A-3: Enterprise Concurrence and Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122

table of contents | 5

appendices

our goalsthe space science enterprise

our goalsthe space sciencethe space science enterprise


i n t roduc t i onThousands of years ago, on a small rocky planet orbiting a modest star in an

ordinary spiral galaxy, our remote ancestors looked up and wondered about their

place between Earth and sky. On the threshold of the 21st century, we ask the

same profound questions:

• How did the universe begin and evolve?

• How did we get here?

• Where are we going?

• Are we alone?

Section I-1Section I-1

8

Today, after only the blink of aneye in cosmic time, we arebeginning to answer these pro-found questions. Using tools ofscience that range from abstractmathematics and computermodeling to laboratories andobservatories, humans are fillingin the details of the amazingstory of the universe. In the last40 years, space probes and spaceobservatories have played a cen-tral role in this fascinatingprocess. Today, NASA addressesthese four profound questionsthrough its many space scienceactivities.

How did the universe beginand evolve? We seek to explainthe earliest moments of the uni-verse, how stars and galaxiesformed, and how matter andenergy are entwined on the grand-est scales. We study astrophysicalobjects, such as neutron stars andblack holes, with extreme condi-tions that demonstrate fundamen-tal laws of physics at work. Westudy the behavior of matter, radi-ation, and magnetic fields under

less severe conditions, in the giantlaboratory of our Solar System.The understanding thus gainedapplies directly to the history andbehavior of stars and galaxies.

How did we get here? We inves-tigate how the chemical elementsnecessary for life have been builtup and dispersed throughout the

cosmos. We look for evidenceabout how the Sun has behavedover time and what effect this hashad on Earth and everything onit. We send probes to other plan-ets to learn about their similaritiesand differences as keys to howthey formed and evolved, andstudy the comets and asteroids inour Solar System for clues to their

introduction | 9

Following the successful December 1999 servicing mission, the Hubble Space

Telescope observed the gravitational bending and focusing of light from very dis-

tant objects by a massive foreground cluster of galaxies.

effects on the evolving Earth. Wecarry out ground-based researchon the environmental limits of lifeto learn how it might have arisenand evolved on early Earth.

Where are we going? Our ultimateplace in the cosmos is wrapped upin the fate of the universe. Nearerto home, the variability of our Sunand vulnerability of Earth to possi-ble impacts by small Solar Systembodies are being investigated. Weare comparing the climate historiesof Earth and its sibling planets.Humanity has taken its first stepsoff our home world, and we will

contribute to making it safe to trav-el throughout the Solar System andwill ascertain what resources possi-ble destinations could offer tohuman explorers.

Are we alone? Beyond astro-physics and cosmology, there liesthe central human question: Arewe on Earth an improbable acci-dent of nature? Or is life, perhapseven intelligent life, scatteredthroughout the cosmos? We seekto explain how planets originatedaround our Sun and other stars—planets that might support life. Weobserve nearby stars for indirect

evidence of other planets, and lookto the future when advancedobservatories in space might beable to directly image such rela-tively small objects across the vastinterstellar void. Beginning withlife found in astonishing places onEarth, we conjecture about whatkinds of environments could bearand support life, and how com-mon habitable planets might be. Isthere now, or has there ever been,life in our own Solar System otherthan on Earth?

Answers to these deep questionswill not be extracted from narrow

| the space science enterprise strategic plan10

Some Recent Space Science Discoveries

In recent years, space research has returned momentous results. Observations from the Hubble SpaceTelescope have yielded much better estimates of the age and size of the universe and the amount ofmatter within it, while x-ray observations from the Rossi X-ray Timing Explorer have led to the discoveryof magnetars, a special type of neutron star that has the most powerful magnetic field known. By map-ping the structure of leftover radiation from the Big Bang, NASA balloon-borne experiments have pro-vided the first firm evidence to date for the “inflation” theory in cosmology. Exotic objects like blackholes, for most of a century just a prediction of abstract mathematics, are now known to be common-place. We are revealing secrets of the inconceivably luminous quasars and gamma ray bursters, nowknown to be in the remotest regions of the early universe. The Chandra X-ray Observatory has revealeda new class of medium mass black holes. Dozens of planet-like objects have been discovered aroundother stars, suggesting that our Solar System is not unique. Interest in the possibility of life elsewherethan on Earth has been galvanized by images of Mars from the Mars Global Surveyor and by evidencefrom the Galileo spacecraft that Jupiter’s moon, Europa, might have a liquid water ocean under an icyouter crust. The structure of our own star, the Sun, and its complex effects on Earth are becoming muchbetter understood. U.S. instruments on the European Solar and Heliospheric Observatory and theJapanese Yohkoh mission have detected “rivers” of flowing gas beneath the Sun’s surface, as well asnew predictors for the occurrence of solar activity that can affect Earth. We have learned much aboutcauses of the solar wind, and even traced individual solar disturbances all the way from the Sun to Earth.

inquiries, but will be built up bycombining innumerable individ-ual clues over the years to come.The broad outlines of much of thepuzzle are discernible now, but aclear picture of the whole awaitsyears of varied research that willundoubtedly produce many sur-prises along the way.

This Space Science EnterpriseStrategic Plan tells about the sci-ence goals and objectives that willlead us toward answers to the fun-damental questions. It lays outour near-term program of activi-ties to pursue these goals andobjectives. It tells how we willinvent and demonstrate the newtechnologies that we need to pur-sue our ambitious vision, and howwe will contribute to human space

flight. And it explains how weplan to share the excitement andunderstanding from our discover-ies with teachers, schoolchildren,and the general public.

In Part I of the Plan, we describeour science goals and objectives,outline how progress in technolo-gy goes hand in hand with ourability to pursue them, and thenpresent our approach to sharingour findings with the public onwhose behalf we are conductingthis important task of discovery.

In Part II we present in moredetail our plans and hopes for theprogram. We describe some excit-ing recent accomplishments andprojects currently under develop-ment, general principles that

guide us in structuring and carry-ing out the program, and our spe-cific mission and research plansfor new activities beginning in2003. In subsequent sections wegive more detail about the tech-nology program that supports ourbold vision, about our basicresearch programs, and about ourpublic education and outreachprograms. NASA cannot succeedwithout the active participation ofscientists, technologists, and engi-neers all over the U.S. and collab-oration with other nations as well.We therefore describe our manypartnerships within the FederalGovernment, across the country,and around the world. The lastsection of Part II presents a visionof the future of the scientificexploration of the cosmos.

introduction | 11

Astrobiology: Science of Synthesis

Answering our fundamental questions will call on all of modern science’s tools of inquiry, ranging fromastronomy, biology, and chemistry, through zoology. To gather these capabilities together and focusthem on our fundamental questions, NASA is nurturing a new multidisciplinary science, Astrobiology.The place of life in the universe and its roots in the origin of the cosmos itself are the themes that runthrough this Strategic Plan to weave the Space Science Enterprise’s many programs together into aunified voyage of discovery.


The Space Act of 1958, which charters NASA as a Federal agency, defines a

broad spectrum of goals and purposes for the Agency. The NASA Strategic

Plan separates responsibility for its programs into Strategic Enterprises, which

identify at the most fundamental level what we do and for whom. Each Strategic

Enterprise has a unique set of goals, objectives, and strategies that address

the requirements of its primary external customers.

12

goa l s and ob j ec t i vesSection I-2Section I-2

Within NASA’s Enterprise struc-ture, the space sciences are gath-ered together into the SpaceScience Enterprise. These spacesciences include space astronomy,planetary exploration, the physicsof the Sun and the space betweenthe Sun and planets, and funda-mental physics experimentationcarried out in space. This docu-ment is the enterprise-levelStrategic Plan for the SpaceScience Enterprise.

The Agency Plan establishes athree-part Agency mission: advanc-ing and communicating knowl-edge, human exploration of space,and developing new technology.Our Enterprise’s programs con-tribute directly to these threeAgency missions. Our role in tech-nology development serves notonly our Enterprise’s and NASA’spurposes, but also the broader pur-pose of strengthening our Nation’stechnology base.

The Space Science Enterprise worksclosely with the scientific communi-ty to articulate science goals that

directly support the Agency researchmission. To address the other ele-ments of the NASA mission, wealso establish Enterprise goals foreducation and public outreach,support to human space flight,and technology. These four goalsdefine the framework for formu-

lating and managing the space sci-ence program.

Within this context, all of ourstrategic planning and manage-ment, including selections formission implementation andrelated research activities, are

goals and objectives | 13

NASA Mission

• To advance and communicate scientific knowledge andunderstanding of Earth, the Solar System, and the universe

• To advance human exploration, use, and development ofspace

• To research, develop, verify, and transfer advanced aeronau-tics and space technologies

The Space Science Enterprise’s foremost role in support of theNASA mission is the discovery of new scientific knowledge aboutthe universe. The Space Science Enterprise will:

Discover how the universe began and evolved, howwe got here, where we are going, and whether weare alone.


Chart the evolution of the universe,from origins to destiny, and under-stand its galaxies, stars, planets,and life

Share the excitement and knowledgegenerated by scientific discovery andimprove science education

Use robotic science missions as fore-runners to human exploration beyondlow-Earth orbit

Develop new technologies to enableinnovative and less expensive researchand flight missions

Enterprise Goals

To advance and commu-nicate scientific knowl-edge and understandingof Earth, the SolarSystem, and the universe

To advance humanexploration, use, anddevelopment of space

To research, develop,verify, and transferadvanced aeronauticsand space technologies

NASA Mission

Table I—Enterprise Goals and Objectives

Science Objectives• Understand the structure of the uni-

verse, from its earliest beginnings toits ultimate fate

• Explore the ultimate limits of gravityand energy in the universe

• Learn how galaxies, stars, and planets form, interact, and evolve

• Look for signs of life in other planetary systems

• Understand the formation and evolution of the Solar System and Earth within it

• Probe the origin and evolution of lifeon Earth and determine if life existselsewhere in our Solar System

• Understand our changing Sun and itseffects throughout the Solar System

• Chart our destiny in the Solar System

Education and Public Outreach Objectives*

• Share the excitement of space sci-ence discoveries with the public

• Enhance the quality of science,mathematics, and technology education, particularly at the pre-college level

• Help create our 21st century scientific and technical workforce

Human Space Flight Objectives• Investigate the composition,

evolution, and resources of Mars, theMoon, and small bodies

• Develop the knowledge to improvespace weather forecasting

Technology Objectives*• Acquire new technical approaches

and capabilities• Validate new technologies in space • Apply and transfer technology

* Associated activities are discussed in Sections I-3 and I-4

Enterprise Objectives

goals and objectives | 15

• Identify dark matter and learn how it shapes galaxies and systems ofgalaxies

• Determine the size, shape, age, and energy content of the universe

• Discover the sources of gamma ray bursts and high energy cosmic rays• Test the general theory of relativity near black holes and in the early uni-

verse, and search for new physical laws using the universe as a laboratory• Reveal the nature of cosmic jets and relativistic flows

• Observe the formation of galaxies and determine the role of gravity in thisprocess

• Establish how the evolution of a galaxy and the life cycle of stars influ-ence the chemical composition of material available for making stars,planets, and living organisms

• Observe the formation of planetary systems and characterize their proper-ties

• Use the exotic space environments within our Solar System as natural sci-ence laboratories and cross the outer boundary of the Solar System toexplore the nearby environment of our galaxy

• Discover planetary systems of other stars and their physical characteristics

• Search for worlds that could or do harbor life

• Inventory and characterize the remnants of the original material fromwhich the Solar System formed

• Learn why the planets in our Solar System are so different from each other• Learn how the Solar System evolves

• Investigate the origin and early evolution of life on Earth, and explore thelimits of life in terrestrial environments that might provide analogues forconditions on other worlds

• Determine the general principles governing the organization of matter intoliving systems and the conditions required for the emergence and mainte-nance of life

• Chart the distribution of life-sustaining environments within our SolarSystem, and search for evidence of past and present life

• Identify plausible signatures of life on other worlds

• Understand the origins of long- and short-term solar variability• Understand the effects of solar variability on the solar atmosphere and

heliosphere• Understand the space environment of Earth and other planets

• Understand forces and processes, such as impacts, that affect habitabilityof Earth

• Develop the capability to predict space weather• Find extraterrestrial resources and assess the suitability of Solar System

locales for future human exploration

Research Focus Areas

Understand the structure of the universe, from its earliest beginnings to its ultimate fate

Explore the ultimate limits of gravity and energy in theuniverse

Learn how galaxies, stars, andplanets form, interact, andevolve

Look for signs of life in otherplanetary systems

Understand the formation andevolution of the Solar Systemand Earth within it

Probe the origin and evolutionof life on Earth and determine iflife exists elsewhere in ourSolar System

Understand our changing Sunand its effects throughout theSolar System

Chart our destiny in the SolarSystem

Science Objectives

Table II—Science Objectives and Research Focus Areas

founded on our science goals andobjectives (Table I). While theseare formulated at a high enoughlevel that we expect them toremain stable over many decades,we continue to refine their articu-lation. In doing so, we work withour research community toupdate our strategic plan, rephras-ing our objectives periodically toreflect our growing knowledge.

Another major function of the tri-ennial review of our EnterpriseStrategic Plan is to articulate nearer-term focus areas for research thatprovide more specific guidance over

a 5-10 year period (Table II). Theseresearch focus areas are derived fromour science objectives in consulta-tion with our research communi-ties, and are phrased to help missionand research decisionmaking andprogress assessment.

The next two sections (I-3 and I-4)describe the roles of technologyand education and public outreachin the space science program. PartII of the plan presents the programitself, beginning in section II-1with our fundamental principles.Sections II-2 and II-3 of the plandescribe our current program and

our proposed flight mission pro-gram for the future. To be as clearas possible about how these mis-sions will advance us toward ourlong-range science aspirations, thepresentation organizes the mis-sions in these sections by the eightEnterprise science objectives laidout above. Appendix A maps themissions onto the more specificEnterprise research activity areas.The remainder of Part II presentsour programs in technology, basicresearch, and education and publicoutreach, as well as our overallstrategies for partnering with otherentities to reach our goals.


Another major function of the triennial review of our Enterprise

Strategic Plan is to articulate nearer-term focus areas for research

that provide more specific guidance over 5-10 year periods.


The space science technology development program develops and makes available

new space technologies needed to enable or enhance exploration, expand our

knowledge of the universe, and ensure continued national scientific, technical,

and economic leadership. It strives to improve reliability and mission safety, and

to accelerate mission development. Since the early 1990’s, the average space sci-

ence mission development time has been reduced from over nine years to five

years or less, partly by integration and early infusion of advanced technologies

into missions. For missions planned in the years 2000 to 2004, we hope to fur-

ther reduce development time to less than four years.

18

t he ro l e o f t echno logySection I-3Section I-3

Our technology program encom-passes three key objectives. First,we strive to develop new and bet-ter technical approaches andcapabilities. Where necessary, wethen validate these capabilities in

space so that they can be confi-dently applied to science flightprojects. Finally, we use theseimproved and demonstratedcapabilities in the science pro-grams and ultimately transfer

them to U.S. industry for publicuse.

To achieve the technology goals formeeting future space science mis-sions capability requirements for-

the role of technology | 19

• Focus technology development on a well-defined set of performance requirements covering the needs of near-term tomid-term strategic plan missions (“mission pull”)

• Guide basic technology research to meet projected long-rangeneeds (“vision pull”)

• Promote partnerships with other agencies, industry, academia, andforeign collaborators to take advantage of capabilities developedelsewhere

• Identify technologies of high value to future Enterprise missionsand fund their development to the point that they are ready forground or space demonstration

• Formulate, develop, and implement cost-effective space demon-strations of selected technologies on suitable carriers

• Use new technologies, in multiple missions where possible, to reducecosts and shorten mission development time across the program

• Maximize benefits to the Nation by stimulating cooperation withindustry, other Government agencies, and academia

Enterprise Technology Activities

Acquire new technical approaches andcapabilities

Validate new technologies in space

Apply and transfer technology

Enterprise Technology Objectives

mulated in science roadmaps, theEnterprise technology strategy is to:

Focus technology developmenton science program requirements.When near-term Enterprise missionconcepts are defined sufficientlyto begin detailed scoping of theirinstrumentation, systems, andinfrastructure, performance require-ments are derived. Technologydevelopment is focused on meeting

the identified requirements (“mis-sion pull” technologies). Basictechnology research is focused onperceived longer range technologyneeds (they are characterized withless precision than near-termrequirements). These longer rangeneeds are generated fromadvanced mission concepts devel-oped by mission study groupsworking with science advisorygroups. Identified needs are then

used to allocate support for matura-tion of more revolutionary technicalapproaches (“vision pull” technolo-gies). The balance between “missionpull” and “vision pull” contributesto program agility and results inlong-term continuing progress ofthe overall program notwith-standing short-term changes incircumstances.

Fund technologies of highvalue to future Enterprise mis-sions to the point that they areready for ground or spacedemonstration. A large numberof technology concepts are giventhe benefit of exploratory researchin the expectation that a fractionof these will emerge as promis-ing. It is critical that these prom-ising candidates for use inmissions are identified and fund-ed to the point where they aretested in a relevant environmenton the ground, adopted by aflight project for further matura-tion, or are proposed as a candi-date for space flight validation.

Formulate and implementcost-effective space demonstra-tions of selected technologieson suitable carriers. Projectmanagers need assurance thatadopted new technology willperform in the relevant spaceenvironment. In many cases thisenvironment can be simulatedon the ground in a satisfactorymanner. Often this is not the


The Space Science Enterprise provides requirements to, and in turn benefits

from, a broad spectrum of Agencywide technology programs.

case, however. It is necessary toidentify those technologies thatrequire space flight demonstra-tion and perform these demon-strations.

Use these technologies in multi-ple missions to reduce costs andshorten mission developmenttime across the program. Sincethe early 1990’s, the average sci-ence mission development timehas been reduced from over nineyears to five years. Although manyfactors can compress missiondevelopment time, infusion of val-idated new technology in the earlymission phases can facilitate this.We compare requirements forfuture missions to look for com-mon needs that can be metthrough a coordinated technologydevelopment effort. Where possi-ble, we sequence missions so thatlater projects build on technologydeveloped and successfully demon-strated for earlier ones.

Promote partnerships with otheragencies, industry, and academiato take advantage of externalcapabilities. Technology infusionsucceeds best through formal andinformal interactions between mis-sion developers, scientific principalinvestigators, and technologyproviders. In the early phases ofdevelopment, detailed analyses andtrade-off studies are conducted todetermine technical feasibility andto establish technology priorities.

Joint activities and partnershipswith universities, industry, andother Government agencies can beparticularly important in speedingidentification and realization of themost attractive technology for spe-cific needs. Technical capabilitiescan sometimes be efficientlyacquired through cooperation withinternational partners. In conduct-ing cooperative activities in tech-nology, the Enterprise protectsproprietary data and intellectualproperty.

Maintain excellence by engag-ing the outside community intechnology development andevaluation. The Enterprise inte-grates industry, academia, andother Federal agencies’ laborato-ries into the program. Industry,for example, develops valuabletechnology by using internalresources (IR&D and profit dol-lars), and through service tonon-NASA customers. Similarly,the university community holdsa vast and unique technologicalresource. University groups,receiving significant fundingfrom other sources, are oftenleaders in essential technologyareas. This approach—of using amix of dedicated peer-reviewedefforts at NASA Centers, otherGovernment agencies, industry,and universities—ensures thatthe “best and brightest” aretapped for the required develop-ments. This approach dovetailswith the practices of followingparallel paths in early develop-ment followed by descoping anddown-selecting. Independentmerit review will be used toassure excellence in both inter-nal NASA and external technol-ogy development efforts. Thesereviews will consider whetherwork is “best-in-class,” con-tributes to specific, document-ed, and otherwise unaddressedEnterprise requirements, and isadvancing significantly thestate-of-the-art.

the role of technology | 21

Technology

infusion succeeds

best through

formal and

informal

interactions

between mission

developers,

scientific principal

investigators,

and technology

providers.


Space science missions have revealed the universe through new eyes and opened

up new worlds to explore and understand. They have shown us that black holes

really exist and have given us fundamental new information about the origin and

evolution of planets, stars, galaxies, and the universe itself. They have opened up the

tantalizing prospect of searching for life beyond Earth. By engaging the imaginations

of teachers, students, and the general public, space science has demonstrated

extraordinary potential for strengthening interest in science and improving the

quality of science, mathematics, and technology education in America. By attracting

bright individuals to advanced study in technical fields, space science also plays

a significant role in ensuring a continuing cadre of trained scientists, engineers, and

technologists to meet our society’s needs in the 21st century.

22

t he ro l e o f educa t i on andSection I-4Section I-4

To meet our goals and objectives,we integrate education and pub-lic outreach into all space science

missions and research programs.The resulting program is animportant element of NASA’s

overall education effort, and wasdesigned in close collaborationwith the NASA Office

the role of education and public outreach | 23

d pub l i c ou t reach

• Incorporate a substantial, funded education and outreach program intoevery space science flight mission and research program

• Increase the fraction of the space science community that contributes to a broad public understanding of science and is directly involved ineducation at the pre-college level

• Establish strong and lasting partnerships between the space science andeducation communities

• Develop a national network to identify high-leverage education and out-reach opportunities and to support long-term partnerships

• Provide ready access to the products of space science education andoutreach programs

• Promote the participation of underserved and underutilized groups in thespace science program by providing new opportunities for minorities andminority universities to compete for and participate in space sciencemissions, research, and education programs

• Develop tools for evaluating the quality and impact of space science education and outreach programs

Education and Public Outreach Activities

Share the excitement of space science discoveries with the public

Enhance the quality of science,mathematics, and technology education, particularly at the pre-college level

Help create our 21st centuryscientific and technical workforce

Education and Public Outreach Objectives

of Human Resources andEducation and the Office of EqualOpportunity Programs. NASAmandates that the Agency “involvethe education community in ourendeavors to inspire America’s stu-dents, create learning opportuni-ties, enlighten inquisitive minds,”and “communicate widely the con-tent, relevance, and excitement ofNASA’s missions and discoveries toinspire and to increase understand-

ing and the broad application ofscience and technology.”

It is our fundamental premisethat all Americans should be ableto participate in the adventure ofexploring and understanding theuniverse. The Enterprise worksclosely with both the space scienceand education communities toidentify education and outreachopportunities focused on the

needs of educators and the gener-al public. Establishing productive,long-term partnerships betweeneducators and space scientistshelps maintain this focus. Oureducation and outreach informa-tion and materials are made read-ily available in a variety of formatsuseful to educators and suitablefor bringing the accomplishmentsof the Space Science Enterprise tothe general public.


Children from the Daniel Boone Regional Library, Columbia, Missouri (a Space Place partner), displaying their own spacecraft—

all made from recycled materials.

our programthe space science enterprise


In section II-3 of this Strategic Plan, we will present missions under study for

development over the 15-year period from 2003 through about 2018. To under-

stand these plans and how they were derived, it helps to review the progress we

have made since our last plan was released in late 1997. In Recent

Accomplishments in this section, we highlight achievements since the last Plan.

Then, in Missions Currently Under Development, we describe missions in an

advanced study stage today that we will begin to implement before the end of

2002. Some of the missions described there will be launched after 2002 and

most will be operating in 2003 and beyond. Missions are presented in bold when

they are first introduced.

28

recen t accomp l i shmen ts Section II-1Section II-1

Recent Accomplishments

The Space Science Enterprise hasmade exciting advances in manygoal areas during recent years. Inthis subsection, we brieflydescribe progress in astrophysicsand cosmology, Solar Systemexploration, technology, andeducation and public outreachprograms.

How did our universe, startingwith what we have come to callthe “Big Bang,” a featurelessprocess that produced only thelightest elements, come to be theplace that we know, rich in therest of the chemical elementsfrom which stars, planets, andlife itself formed? The opportu-nity to put instruments in spacethat observe at many wave-lengths has provided us with anexplosion of evidence addressingthese questions.

In the late 1980’s, the CosmicBackground Explorer (COBE)satellite gave us a glimpse of thebeginnings of structure very earlyin the history of the universe, a view sharpened by the subse-quent BOOMERANG balloon-borne observations. The ComptonGamma Ray Observatory (CGRO)observed evidence for the synthesisof heavy elements in supernovaexplosions and their subsequentspread throughout the Milky Way.It observed large numbers of mys-terious gamma ray bursts; believednow to originate in very distantsources, these brief gamma ray

“flashes” must represent enormousamounts of emitted energy. Vastamounts of energy in gamma raysare also seen to be coming from thejets in distant galaxies.

Two x-ray satellites, the Rossi X-rayTiming Explorer (RXTE) and theJapanese-U.S. ASCA mission, havehelped us understand disks ofaccreting material in binary systemsand provided evidence for spinningblack holes in active galactic nuclei.

Recently, the newly launchedChandra X-ray Observatory(CXO) is showing us details of the

recent accomplishments and current program | 29

s and cu r ren t p rog ram

The Chandra x-ray image shows the

complex region around Eta Carinae,

a massive supergiant star that is

7,500 light-years from Earth. The

outer horseshoe shaped ring is about

two light-years in diameter and was

probably caused by an outburst that

occurred more than a thousand

years ago.

structure and composition of objectswe could only begin to see a fewyears ago. For example, Cassiopeia-Ais a supernova remnant alreadyknown to be a powerful emitter ofradio waves. A CXO x-ray image ofit (shown on the Plan cover) showswith remarkable clarity, not only thewispy structure characteristic of asupernova remnant, but also whatappears to be a neutron star at thecenter, the remaining denselypacked core of the original star.These exciting results are show-cased through a nationally-distrib-uted planetarium show “Journeyto the Edge of Space and Time,”co-produced by the BostonMuseum of Science, which takeshundreds of thousands of viewersper year on a spectacular voyagefrom the Milky Way to the farthestreaches of our universe.

New results on the elemental andisotopic composition of solar parti-cles, galactic cosmic rays, and thesolar wind are being achieved by the Advanced CompositionExplorer (ACE). The observa-tions have shown that galactic cos-mic rays are boosted to theirenormous energies from thedebris of supernovae, but longafter the supernova explosionsthemselves. In a surprising andunrelated discovery, ACE foundthat the solar wind came to a vir-tual standstill for two days in May1999. This event, believed to berelated to a massive ejection of

material from the Sun, stronglyaffected Earth’s magnetosphere.

Another recent mission, theSubmillimeter Wave AstronomySatellite (SWAS) studies theprocesses of star formation byobservations of water, molecularoxygen, isotopic carbon monox-ide, and atomic carbon. Results ofobservations of dark interstellarclouds, evolved stars, external

galaxies, and planetary nebulaeconfirm some of our ideas aboutinterstellar chemistry, but havecontradicted our expectationsabout the amount of oxygen andwater in many cool molecularclouds.

NASA has made rapid advances inits goal toward tracing our cosmicroots through a better understand-ing of the formation of galaxies,


Glowing like a multi-faceted jewel, the planetary nebula IC 418 lies about 2,000

light-years from Earth in the constellation Lepus. The Hubble Space Telescope

reveals some remarkable textures weaving through the nebula. Their origin is

still uncertain.

stars, heavy elements, and plane-tary systems. Discoveries by theHubble Space Telescope (HST)have invigorated astronomy inmany areas. Astronomers haveobserved details of the surfaces orouter layers of Mars, Saturn,Jupiter, Uranus, and Plutothrough visible, ultraviolet, andinfrared images taken by HST.The crisp resolution of HST hasrevealed various stages of the lifecycle of stars in images of galacticnebulae. After a multi-year observ-ing and analysis program, HSThas enabled us to refine our esti-mate of the Hubble Constant, therate at which the universe isexpanding. This determines theage of the universe since the BigBang to a precision of 10 percent,compared to the previous factor-of-two uncertainty. Thousands of

never before seen galaxies havebeen observed in the Hubble DeepFields, doubling the number offar-flung galaxies available fordeciphering the history of the uni-verse. HST continues to hold thefascination of students, teachers,and the public, making the “NewViews of the universe” travelingexhibit a highly popular destina-tion for museum and science cen-ter visitors nationwide. Twoversions of the exhibit, appropriatefor large and small museums, arenow traveling around the country,allowing visitors to experienceHubble’s discoveries and knowl-edge through interactive learning.

The Far Ultraviolet SpectroscopicExplorer (FUSE) is providingvery high resolution ultravioletspectra of the interstellar medi-um, giving information on thechemical content of materialbetween stars and galaxies. Theultimate goal is to discover theconditions at the time of the BigBang and how the universe hasevolved since then.

Over the past few years, NASA-supported ground-based researchhas discovered dozens of sub-stellarcompanions orbiting nearby stars.

Turning to the Solar System, datafrom the Mars Orbiter LaserAltimeter (MOLA) instrumenton the Mars Global Surveyorspacecraft show evidence for an


Galactic assembly and reconstruction: A typical high-latitude sight line through

the Milky Way encounters interstellar clouds near the galactic plane and dis-

tant clouds in the outer regions of the galactic halo. Distant clouds fall in on the

galaxy from the outside (assembly), while nearby gas is circulated and ener-

gized by supernovae (reconstruction). FUSE can diagnose these processes by

examining the absorption of light passing through these clouds.

Astronauts replace gyroscopes

inside the Hubble Space Telescope

during the HST-3A mission.

ancient ocean basin around theplanet’s north pole. These data,which comprise over 200 millionhigh-precision measurements ofthe height of Mars’ surface, indi-cate an ancient shoreline about18,000 km long. The amount ofwater that would have been con-tained in the ocean is about whatwould be expected on the basis of other geological features suchas the outflow channels that draininto the northern lowlands of the planet.

Since its continuation in 1998as the Galileo Europa Mission(GEM), Galileo has concentrat-ed on intensive study of Jupiter’sice-covered satellite Europa. Ithas been known for nearly 30years that Europa is coveredwith a crust of water ice; what is

not known is whether the iceextends all the way down tobedrock or floats on an ocean ofliquid water. The possibility of aliquid ocean is extremely excit-

ing because of the implicationsfor Europa as a possible habitatfor life. GEM has yielded sever-al lines of evidence that supportthe hypothesis of liquid water


Top:

Global topographic map of Mars.

The Mars Orbiter Laser Altimeter

(MOLA) instrument on the Mars

Global Surveyor spacecraft suggests

what was once a vast ocean (blue

indicates lower elevations).

Bottom:

Eruption in Tvashtar Catena, a chain

of volcanic calderas (craters) on

Jupiter’s moon Io, as seen by NASA’s

Galileo spacecraft. The temperature

of the lava is much higher than is typ-

ical for volcanic eruptions on pres-

ent-day Earth.

beneath its icy crust. Galileo hasalso obtained dramatic images ofother satellites of Jupiter,including vulcanism on thesatellite Io.

The Cassini mission to Saturn,launched in 1998, has successfullycompleted three gravity assistmaneuvers, two at Venus and oneat Earth. A fourth and final gravi-ty assist maneuver at Jupiter inDecember 2000 will put Cassini

on a trajectory for arrival at Saturnin July 2004.

The first two Discovery missionswere Mars Pathfinder and theNear Earth Asteroid Rendezvous(NEAR). Pathfinder dramatical-ly brought Mars exploration totelevision viewers and Internetusers all over the world with itsclose-ups of the Mars surface.After missing its first rendezvouswith asteroid 433 Eros in 1998,

NEAR has returned to be suc-cessfully placed into orbitaround the asteroid and returnhigh quality images, spectra, andaltimetry.

Lunar Prospector, the thirdDiscovery mission, successfullycompleted global spectroscopyand gravitational mapping of theMoon. The highlight of this mis-sion was the discovery of evidencefor trapped hydrogen, possibly inthe form of water ice, in perma-nently shadowed craters near bothlunar poles. Lunar Prospectorepitomized the “faster, better,cheaper” goals of the Discoveryprogram. It was developed, fromproject initiation to launch, in lessthan three years; it successfullycompleted all of its scientificgoals; and it was by far the leastexpensive planetary explorationmission ever flown by NASA.Stardust, the fourth Discoverymission, was launched in January1999. It will collect a sample ofdust from the coma of cometWild-2 in 2004 and return thesample to Earth for detailedanalysis in 2006.

In 1998, the Transition Regionand Coronal Explorer (TRACE)joined an international fleet of spacecraft, including theInternational Solar TerrestrialProgram (ISTP) satellites Windand Polar, Yohkoh, Ulysses, andACE, for coordinated multi-


Left: This NEAR-Shoemaker image taken from an orbital altitude of 38 kilome-

ters brings home the irregularity of the tiny world called Eros. Looking down the

length of the asteroid, one sees near, middle, and far horizons. The whole

scene is about one kilometer across.

Right: The million-degree solar plasma shown by TRACE shows a set of loops,

possibly brought on by a large flare occurring a few hours earlier.

dimensional study of the Sun-Earth connection and the impactsof solar variability on Earth. Atthe very low cost of a SmallExplorer mission, TRACE hasprovided dramatic, high resolu-tion motion pictures of evolvingstructures in the solar atmos-phere that clearly show theeffects of magnetic activity. ThePolar spacecraft obtained thefirst global images of Earth’sspace environment using fast

neutral atoms instead of light to“see” the plasma motions. TheESA Solar and HeliosphericObservatory (SOHO), in whichNASA is a major collaborator, hasprovided evidence for streams of hotplasma under the solar surface, aswell as dramatic movies of massiveblobs of ionized gas, a billion tons insize, being expelled from the Sun.

The Fast Auroral SnapshotExplorer (FAST) satellite, which

measures particles and fields inEarth’s auroras with fast time reso-lution and high spatial resolution,has found the origin of long-wavelength radio emission fromthese regions. This process, whichdepends on the geometry of mag-netic and electric fields, mayexplain previously mysterious par-ticle acceleration in astrophysicalplasmas in many settings outsidethe Solar System. The Imager forMagnetospheric to AuroraGlobal Exploration (IMAGE) isgiving us a new perspective on theresponse of Earth’s magnetosphereto the solar wind using a combi-nation of neutral atom, ultravio-let, and radio imaging techniques.

These measurements are beingcomplemented by data from U.S.instruments on ESA’s Cluster-IImission, which consists of fouridentical spacecraft flying in for-mation between 25,000 and125,000 km above Earth.

The popularity of total solar eclipseshas provided unique, high-leverageopportunities to highlight solar andgeospace research conducted bymissions such as SOHO, TRACE,and IMAGE. Eclipse webcastevents produced by the Live@TheExploratorium program from thepath of totality offer participatingspace scientists the chance to discusstheir research with thousands of vis-itors at museum sites around thecountry and through the Internet.


The IMAGE spacecraft observed highly dynamic auroral activity over the ter-

restrial pole during the major geomagnetic storm that occurred May 2000.

The New Millennium Programfor flight technology validation wasinitiated with the Deep Space 1(DS-1) mission. DS-1 successfullyvalidated all twelve new technolo-gies onboard for demonstration.Some of these technologies willenable future spacecraft to be builtsmaller and less expensively; otherswill increase spacecraft navigationautonomy, reducing operationscosts.

Deriving the full benefit of thepublic investment in space sciencerequires that its discoveries beshared with all Americans. Since

the publication of the 1997 SpaceScience Enterprise Strategic Plan,we have made major progresstoward incorporating Educationand Public Outreach into everyfacet of our programs. This sec-tion highlights a few examples ofEducation and Public Outreachprograms connected with flightmissions. In addition, an activepublic information program,including widely reported SpaceScience Update press events, hashelped bring results of space sci-ence missions to public attentionthrough print and electronicmedia. All flight missions are now

required to have substantive,funded education and public out-reach programs as integral compo-nents. Participants in researchgrant programs are also stronglyencouraged to include an educa-tion and outreach component aspart of their research proposals. Asa result, literally hundreds of edu-cation and public outreach activi-ties of many different types arenow underway in communitiesacross the country. These activitieshave already benefited many stu-dents and educators and havereached a large segment of thepublic.


New Technologies Successfully Space-Validated by Deep Space 1Ion Drive for Primary PropulsionSolar Concentrator Arrays Autonomous Navigation Ion and Electron Spectrometer Small Deep Space Transponder Ka-Band Solid State Amplifier Beacon Monitor Operations Autonomous Remote AgentLow Power Electronics Power Actuation and Switching Module Multifunctional StructureMiniature Integrated Camera

and lmaging Spectrometer

During a highly successful primary

mission, DS-1 tested 12 advanced

technologies in space.


Examples of Education and Public Outreach Activities Underway

1. A teacher resource directory provides access to space scienceeducation and outreach products for use by educators.

2. We have used workshops for teachers in communities across thecountry and national education conferences to test and distributeeducation products to tens of thousands of teachers.

3. Space science-centered exhibits are on display at a number ofmajor science museums, and space science-based shows areplaying at large and small planetariums across the country.

4,5. The internet is being routinely used as a tool for disseminatingspace science classroom materials and bringing major space sci-ence events to the public.

1

2 3

4 5

Missions CurrentlyUnder Development

Building on the exciting resultsof missions completed or stilloperating, many missions thatwere only proposals in our 1997plan are graduating from theirstudy phases into developmentand will be launched within thenext few years.

The Microwave AnisotropyProbe (MAP) Explorer will meas-ure fluctuations in the microwavebackground on angular scalesmuch finer than COBE, fluctua-tions out of which the largeststructures in the universe—thesuper-clusters of galaxies—even-tually emerged. MAP shouldenable us to measure directly thesize and contents of our universeat an age of only 300,000 years.Later, with even finer angularresolution and sensitivity, theEuropean Space Agency (ESA)/NASA Planck mission will pro-vide precision measurements ofdark-matter, baryon, vacuum-energy densities, and the Hubbleconstant, and thus forecast theultimate fate of the universe.Planck’s polarization measure-ment capabilities will allow newand unique tests of cosmologicalinflation and perhaps measure itsenergy scale.

HST’s new instruments areexpected to continue the observato-

ry’s spectacular accomplishments.These upgrades include the instal-

lation of the Advanced Camera forSurveys, a new cooling system toreactivate the Near Infrared Cameraand Multi Object Spectrometer, theCosmic Origins Spectrograph,and the Wide Field Camera-3.The next major space observatorywill be the Space Infrared Tele-scope Facility (SIRTF). Once inoperation, SIRTF will contributeextensively to the understandingof formation of stars and planetsand will investigate the formationand early evolution of luminousgalaxies.

While SIRTF will have unsur-passed sensitivity throughout theinfrared wavelength regime, the


SIRTF is the final element in NASA’s family of “Great Observatories,” and con-

sists of a cryogenic telescope and science instruments for infrared imaging and

spectroscopy.

HST’s new

instruments are

expected to

continue the

observatory’s

spectacular

accomplishments.

Stratospheric Observatory forInfrared Astronomy (SOFIA)will complement the space mis-sion with much better spatial andspectral resolution for the detailedstudy of bright objects. A key sci-entific goal of SOFIA will be theinvestigation of conditions withinthe interstellar medium thatenable the formation of stars andplanets. As an aircraft, rather thana space observatory, SOFIA hasseveral unique characteristics. Itcan continually upgrade its instru-mentation and serve as a criticaltraining ground for new genera-tions of instrument builders.

The ESA-led Far-Infrared andSubmillimeter Telescope (FIRST)will be able to observe very dustygalaxies with active star forma-tion out to large distances, andtherefore early in the universe.FIRST will also be able to studymolecule formation in the densemolecular clouds in our owngalaxy where stars and perhapsplanets are forming.

The Keck Interferometer, aground-based facility, will com-bine the infrared light collected bythe world’s two largest optical tel-escopes, the twin 10-meter Kecktelescopes on Mauna Kea inHawaii, to undertake a variety ofastrophysical investigations.

The most violent events in the Uni-verse emit bursts of gamma rays for

a few seconds. Observations withthe Italian/Dutch Beppo-SAXsatellite, complemented withresults from the Compton GammaRay Observatory (CGRO), haveshown that these mysterious eventsoccur early in the history of galax-ies and are clues to major events intheir evolution. The Explorer mis-sion Swift, and later the GammaRay Large Area Space Telescope(GLAST) will enable us to unlockthe mysteries of these dramatic stel-lar explosions. Because of their greatdistances from us, spectral studies ofthese explosions will allow us toprobe the intervening infrared back-ground light, which absorbs the

higher energy gamma ray photonsthrough electron-positron pair pro-duction. GLAST will also study thenature of cosmic jets and relativisticbipolar flows emanating from dis-tant active galactic nuclei, anddetermine how much of the generalall-sky diffuse gamma ray back-ground is due to such sources,which were unresolved by instru-ments of the Compton GammaRay Observatory. In addition,GLAST will pursue the surprisingdiscovery of the trickle of highenergy gamma rays observed tocontinue to issue from somegamma ray bursters, sometimesfor hours.


SOFIA will involve educators directly in its research programs by flying them on

the observatory itself and centering its education and public outreach pro-

grams on these opportunities.

Explorer missions with targetedscience objectives will comple-ment major missions and insome cases provide key informa-tion that will help maximize thescientific return from them. TheGalaxy Evolution Explorer(GALEX) will use high resolu-tion ultraviolet spectroscopy andimaging to observe star forma-tion over 80 percent of the life-time of the universe, the periodthat spans the origins of moststars, elements, and galaxy disksand over which galaxies haveevolved dramatically. The Full-Sky Astrometric Explorer(FAME) will be a space astrome-

try mission that offers theunique opportunity to measurethe positions, proper motions,parallaxes, and photometry offorty million stars to unprece-dented accuracy. Through thesedata, the variability of 40,000solar type stars will be character-ized, the frequency of solar typestars orbited by brown dwarf andgiant planet companions will bedetermined, and the distancescale of the universe will beimproved. The Cosmic HotInterstellar Plasma Spectrometer(CHIPS) will carry out spec-troscopy of the diffuse back-ground in the extreme ultraviolet

to determine the evolution of themillion degree gas that lies out-side the Solar System. This willlead to an understanding of keymechanisms responsible for recy-cling gas within the interstellarmedium.

Planning and development con-tinues for new missions in theMars Exploration Program(MEP). The losses of the MarsClimate Orbiter and Mars PolarLander in 1999 were severeblows to the program, but scien-tific interest in Mars as a labora-tory for comparative planetologyand as a possible home for pastor present life continues undi-minished. Responding to reviewsof these failures, we are planninga flight program firmly based onscientific objectives and will exe-cute it at a pace consistent withtechnical readiness and availableresources. Return of samples toEarth for analysis remains animportant objective, but near-term missions will focus onorbital science, in situ analysison the surface, and characteriza-tion of possible landing sites.The next mission will be anorbiter to be launched in 2001,and two enhanced rovers will fol-low in 2003.

The Galileo Europa Mission’sintensive study of Europa hasyielded evidence for a global liq-uid water ocean beneath the icy


The innermost and outermost circles outline the volume covered by the

Hipparcos and FAME missions, while the symbols mark the positions of two

types of stars that can be used as cosmic yardsticks.

crust. Although this evidence isnot conclusive, this would be sucha momentous discovery that weare planning a Europa Orbitermission system to obtain a defini-tive answer. Advanced technolo-gies needed for this mission arebeing developed, and implemen-tation of this follow-on missioncould begin in the 2002-2003timeframe.

A number of new Discovery mis-sions that address related topics arein development. The CometNucleus Tour (CONTOUR) willfly by the nuclei of at least twocomets at different evolutionarystages. CONTOUR will analyzethe surface structure and compo-sition of these nuclei to probethe diversity of comets. DeepImpact will excavate a crater incomet Temple-1 to study thestructure of the cometary nucleusand to compare its interior com-position with that of its surface.The objective of doing so is togain a better understanding ofthe history of primordial materi-al from the outer Solar System.As one component of the mis-sion’s public outreach program,the International AstronomicalLeague will set up opportunitiesaround the world to allow thepublic to observe the impact.

Another Discovery mission nowunder development, the MercurySurface, Space Environment,


Mariner 10’s first image of Mercury, acquired on March 24, 1974. Closer study

of Mercury’s high density, global magnetic field, and ancient surface will pro-

vide important clues for understanding the evolution of the inner Solar System.

Geochemistry and Ranging(MESSENGER) mission, willstudy how the inner Solar Systemformed by analyzing the physicalproperties and chemical compo-sition of the closest planet to theSun. The planet Mercury will be the focus of an ambitiouseducation and public outreachprogram aligned with NationalScience Education Standards forteaching and learning under theauspices of the AmericanAssociation for the Advancementof Science, the Challenger Centerfor Space Science Education, andseveral other national partners.

New insight into the materialfrom which the Sun itself origi-nally formed, still preserved inthe outer atmosphere of the Sun,will be obtained by the Genesismission when it collects andreturns to Earth samples of thesolar wind that streams out fromthe Sun.

The Sun profoundly affects allthe bodies in the Solar System, aswell as the space between them.To explain these effects, we needto understand both the inherentcharacteristics of the Sun andhow its emissions interact withthe rest of the Solar System.Missions currently under devel-opment will advance our knowl-edge of the Sun’s interiordynamics. Coordinated measure-ments of events that originate on

the Sun, propagate through inter-planetary space, and ultimatelyimpact on Earth’s magnetosphereand upper atmosphere areenabling us for the first time todetermine cause and effect unam-biguously. This research will bepursued within the new Livingwith a Star initiative, which willaccelerate some currently plannedmissions and support new onesnow being defined. For Livingwith a Star, the University ofCalifornia-Berkeley Space ScienceLaboratory and the LawrenceHall of Science are developingelementary and middle schoolactivities highlighting the impactof the active Sun on Earth andsociety. These activities will be

part of the “Great Explorations inMath and Science” series, whichis already used by thousands ofschool districts nationwide.

The Solar Terrestrial Probe (STP)program is a line of missions thatstudy the Sun-Earth system. TheSTP program seeks to understandsolar variability on time scales froma fraction of a second to many cen-turies. It will also correlate cause(solar variability) with effect overvast distances. The STP programwill begin with the launch of theThermosphere-Ionosphere-Mesosphere Energetics andDynamics (TIMED) mission,which will provide a first globalcharacterization of the regionwhere the atmosphere tails off intospace. TIMED will be followed by two missions that will addresssolar variability from differentperspectives. NASA’s contribution to Solar-B (a mission of theJapanese Institute of Space andAstronautical Science) will be thesecond STP mission. Solar-B willinvestigate the creation anddestruction of the Sun’s magneticfield and provide quantitativemeasurements of the photosphericfield with greatly improved spatialresolution. The third STP missionis the Solar Terrestrial RelationsObservatory (STEREO), twoidentical spacecraft that willobserve the Sun stereoscopicallyfor the first time. STEREO willtrack the origin, propagation, and


The Galileo

Europa Mission’s

intensive study

of Europa has

yielded evidence

for a global

liquid water

ocean beneath

the icy crust.

evolution of coronal mass ejections,powerful disturbances that trav-el from the Sun to Earth’s orbitand beyond.

Explorer program missions nowunder development will supple-

ment the STP missions. The HighEnergy Solar SpectrographicImager (HESSI) will explore thebasic physics of particle accelera-tion and energy release in solarflares using simultaneous, high res-olution imaging and spectroscopy

in x-rays and gamma rays withhigh time resolution. The TwoWide-angle Imaging Neutral-atom Spectrometer (TWINS)mission, in combination withIMAGE, will enable a three-dimensional visualization of Earth’s


STEREO will measure coronal mass ejections from the Sun in three dimensions for research to increase reliability of space

weather alerts.

magnetosphere and resolution oflarge scale structures and dynam-ics within it by applying tech-niques similar to those of theIMAGE mission from two widelyspaced high-altitude, high-incli-nation spacecraft.

The frequent access to space pro-vided by smaller space missionshas accelerated scientific and tech-nical innovation in the space sci-ences. Balloon-borne payloadsprovide similar benefits at stilllower cost. Observing from thetop of the stratosphere, a new gen-eration of Ultra-Long Duration

Balloons (ULDB’s) that offer 100days or more of observing time perflight is now under development.We expect this new capability toenable important and very cost-effective observations in suchdiverse areas as solar physics andinfrared and hard x-ray astronomy.

All of the missions under devel-opment include substantial edu-cation and public outreachcomponents that are well inte-grated with the activities of thescience and technical teams. Insupport of these space scienceeducation and outreach efforts,

we have established a nationalnetwork of 10 institutions acrossthe country to serve as a bridgebetween the education, publicoutreach, and space science com-munities. The goals of this insti-tutional infrastructure are toimprove effectiveness of the spacescience community’s participa-tion in education and public out-reach, to coordinate the diverseeducation and public outreachactivities undertaken by space sci-ence researchers across the coun-try, and to assure nationalavailability of the resulting pro-grams and products.



Our approach to accomplishing Enterprise science goals is founded on a set of

fundamental principles that encompass the role of space science within NASA,

program planning and structure, project management axioms, our relationship

to our scientific stakeholders, the role of technology, our responsibilities to the

public, and guidelines for international cooperation. This section presents these

principles and then describes our strategic and tactical planning processes.

44

pr i nc ip l es and p rocessesSection II-2Section II-2

General Principles

Use scientific merit as the pri-mary criterion for program plan-ning and resource commitment.The Space Science Enterprise is firstand foremost a science program,among many activities conducted

by NASA. The scope of NASA’smission as provided in the SpaceAct of 1958 ranges from pureknowledge to advancing the state ofpractical know-how in many areasfor the benefit of U.S. industry. Inthis context, NASA’s space scienceprograms also contribute to other

national purposes as secondaryobjectives. The primary means forestablishing merit for Enterpriseprograms are open solicitation andcompetitive peer review.

Base the Enterprise Strategic Planon science goals and objectives,

principles and processes | 45

es

Peer Review

It is Enterprise policy that funding to support research and mission development be allocated byprocesses that use peer review to establish scientific merit. NASA uses the following uniform,Agencywide definition for peer review:

Peer review is a scientific evaluation by an independent in-house specialist, a specialist out-side of NASA, or both, of proposals submitted in response to NASA research announcements,announcements of opportunity, and cooperative agreement notices. Peer review is also usedto evaluate unsolicited proposals. Peer reviews evaluate relevance to NASA’s objectives,intrinsic merit that includes scientific or technical merit of research methods, the researcher’scapabilities and qualifications, and cost.

All selected science investigations must achieve a top rating for peer reviewed science merit. In mak-ing final selections, however, other factors besides science merit also have a role. These factors includealignment with Enterprise goals, national and Agency policy, program balance, available budgets, tech-nological readiness, various types of risk, and contributions to education and public outreach.

For the special class of the New Millennium technology flight validation missions, technology consid-erations provide the primary selection criteria.

and structure its research andflight programs to implementthese goals. These plans are devel-oped every three years. Scienceobjectives are set in partnershipwith the scientific community, andmission formulation is based onthese science objectives within poli-cy and budget constraints estab-lished by the Administrator, thePresident’s Office of Managementand Budget (OMB), and Congress.In planning, the first rule is to com-plete missions already started,except in the case of insuperabletechnical or cost obstacles. TheEnterprise defines missions via itsstrategic planning process (generallylarger missions) and incorporatesmissions formulated by the scientif-ic community (e.g., Explorer andDiscovery). While recognizing thatnot all scientific objectives can be

attained by small missions, theEnterprise emphasizes the “faster,better, cheaper” paradigm, whereappropriate, to accelerate exploita-tion of new technological and scien-tific opportunities.

Aggregate consecutive missionsthat address related science objec-tives into “mission lines.” It ismuch easier to explain broad scienceobjectives and a program of relatedmissions to Agency stakeholders andthe general public than it is to con-vey the significance of individualmissions, which is often much moretechnical. Further, a stable fundingprofile for a series of related missionspromotes continuity and flexibilityin budget and technology planning.In structuring the flight programinto mission lines, the first priorityis to preserve and extend existing

lines. The second priority is todevelop and establish new missionlines corresponding to new highpriority science objectives. This isdone by identifying and advocatingcompelling pathfinder missions forthe new lines.

Preserve safety as NASA’s numberone priority; this includes missionsuccess for robotic flight projects.Properly implemented, the “faster,better, cheaper” approach does notjeopardize this priority. Projectswill not be approved for implemen-tation until a clear technology pathto successful implementation isdemonstrated. Each Enterpriseflight project will maintain reservesappropriate to its level of technicalrisk, and testing and reviews will beadequate to provide positive engi-neering assurance of sound imple-


Mission Formulation

Strategic, or NASA-formulated, missions are defined by NASA, with guidance from members of thespace science community. Science payloads and investigations are then selected competitively bymeans of peer review in accordance with the principles set forth in NASA’s Science Policy Guide.Examples of this category of missions are major space observatories, Mars Exploration Program mis-sions, and Solar Terrestrial Probes.

Community-formulated missions, in contrast, are designed totally by science community-industryteams and selected by NASA through competitive peer review as complete packages. These missionsadd flexibility, rapid response to new opportunities, and frequent access to space. This category ofmissions includes the Explorer and Discovery lines.

All selected and implemented missions, whether NASA-formulated or community-formulated, addressscience goals and objectives in the Enterprise Strategic Plan.

mentation. In the event of projectcost growth, reserves will be main-tained by reallocation of resourceswithin the project’s science themearea, by schedule delays, or bydescoping. If these measures are notsufficient, or if the necessarydescoping diminishes expected sci-entific returns below the project’sscience requirements floor, the mis-sion may be canceled. Resourceshortfalls will not be relieved bydeviating from proven space systemengineering and test practices.

Ensure active participation of theresearch community outside NASAbecause it is critical to success. Theoutside community contributesvitally to strategic and program-matic planning, merit assurance viapeer review, mission executionthrough participation in flight pro-grams, and investigations support-ed by research grants programs. Inaddition, NASA science and tech-nology programs conducted at theuniversities play an important rolein maintaining the Nation’s aca-demic research infrastructure andin developing the next generationof science and engineering profes-sionals, whether they pursue spaceresearch careers of their own orapply their technical skills else-where in the economy.

Maintain essential technical capa-bilities at the NASA Centers.NASA has significant scientific andtechnological capabilities at its

Centers. NASA Center scientistsprovide enabling support to thebroader research community byserving as project scientists andoperating unique Center facilities,and compete with external re-searchers for funding to conducttheir own original research. Centerstaff maintain “corporate memory”for Enterprise programs and provideessential engineering support as well.

Apply new technology aggres-sively, within the constraints of prudent stewardship of publicinvestment. Research in space sci-ence pushes the boundaries of ourtechnical capabilities. The relation-ship between science and technolo-gy continues to be bi-directional:scientific goals define directions forfuture technology investment anddevelopment, while emerging tech-nology expands the frontier of pos-sibilities for scientific investigation(sections I-3 and II-4). To maintainthe balance between risk andreward, new technologies aredemonstrated wherever possible viavalidation in flight before incorpo-ration into science missions. Thispolicy is implemented through theNew Millennium program, inwhich technology demonstration isthe primary objective and scienceplays a secondary role.

Share the results and excitementof our programs through the formal education system and pub-lic engagement. A fundamental

consideration in planning andconducting all of our programs isthe recognition that the nationalinvestment in space science is apublic trust and the public has aright to benefit from our work. Todischarge this commitment, weuse not only print and electronicnews media, but also museum andother exhibits and material forformal pre-college education. Toensure infusion of fresh resultsfrom our programs into theseeducational efforts, our policy isthat each flight project must havean education and outreach com-ponent. The Enterprise has estab-lished a nationwide supportinfrastructure to coordinate theplanning, development, and dis-semination of educational materi-al (sections I-4 and II-6).

Structure cooperation with inter-national partners to maximizescientific return within the frame-work of Enterprise Strategic Planpriorities. The Space Act of 1958provides that NASA shall cooper-ate in peaceful space activitieswith other nations. Today, most ofthe Enterprise’s flight programshave international components(section II-7). In establishingthese cooperative relationships, asindeed in all other aspects of ourprogram, funding is allocated toU.S. participants in internationalprograms through competitivepeer review. Foreign participants inU.S. missions are likewise selected


on the basis of merit. In general,NASA seeks to lead where possible,and participate with our partnersthrough collaborative roles in otherdeserving areas.

Strategic Planning

From its beginnings, NASA spacescience has based its planning on a foundation provided by theNational Academy of Sciences. TheAcademy’s Space Studies Board (for-merly the Space Science Board) andits committees critically assess thestatus of various space science disci-plines, identify the most promisingdirections for future research, outlinethe capabilities required, identifytechnologies needed to attain thosecapabilities, and examine the role ofeach mission in the context of thetotal space science program.Enterprise science goals, objectives,and missions can all be traced toAcademy recommendations.

Synchronized with the triennial revi-sion of the Agency Strategic Planmandated by the GovernmentPerformance and Results Act of1993 (GPRA), the Enterprise revis-es its own Strategic Plan at the sameinterval. In addition to general infor-mation about program and plan-ning processes, the Enterprise Planlays out science goals and scienceobjectives and mission plans for thenear- and mid-term. The near-termis a five-year period that starts

approximately two fiscal years fromthe date of issue of the Plan, whilethe mid-term extends about adecade beyond that. The EnterprisePlan describes near-term missionsand how they address science goalsand objectives in more detail than itdoes mid-term missions, which arepresented briefly and schematically.Each release of the Plan also presentsinformation about the Enterprise’stechnology needs and activities anda review of education and publicoutreach goals and programs.

The Enterprise works with thespace science community todevelop each Enterprise StrategicPlan. This work is done throughNASA-formed advisory commit-tees (the Space Science AdvisoryCommittee and its subcommit-tees) with assistance from ad hocplanning groups, input from thegeneral science community, andtechnical support from NASA’sCenters. Development of the2000 Plan illustrates the process.

Work on the 2000 plan began in late1998, when the Enterprise’s ScienceBoard of Directors initiated thedevelopment of science and technol-ogy roadmaps for each Enterprisescience theme (Astronomical Searchfor Origins, Structure and Evolutionof the Universe, Solar SystemExploration, and Sun-Earth Con-nection). These roadmaps—whichwere developed by roadmappingteams that included scientists, engi-

neers, technologists, educators, andcommunicators of science—addressscience goals, strategies for achievingthese goals, missions to implementthese strategies, technologies toenable these missions, and opportu-nities for communicating with thepublic. Each roadmapping team waseither built from or overseen by itstheme subcommittee of the SpaceScience Advisory Committee. Theteams each held a series of meetingsto obtain science priority views fromcommunity scientists, hear advocacypresentations for specific missions,examine technology readiness foralternative mission options, and dis-cuss relative science priorities, balance, and optimum activitysequencing in light of this informa-tion. One technique used to fosterconvergence was taking straw pollsamong team members during suc-cessive meetings.

At the end of the roadmapping period, each of the four themeroadmapping activities submitteda summary document outliningscience and mission recommenda-tions to the Space ScienceAdvisory Committee and toEnterprise Headquarters manage-ment. Enterprise managementthen combined the mission rec-ommendations of the roadmap-ping teams into an integratedmission plan, guided by the cur-rent OMB five-year budget pro-file, realistic estimates of mostlikely future resource availability


beyond that, and additionalAgency-level and Administrationguidance. Likewise, science goalsin the roadmaps were used toexamine and restate those present-ed in the 1997 Enterprise Plan.

An integrated roadmap was present-ed and discussed at a planning work-shop that expanded the membershipof the Space Science AdvisoryCommittee with other communitymembers and representatives fromthe technology and education andpublic outreach communities.Attendees at the workshop also ana-lyzed and revised the proposedupdated science objectives, andderived a new set of shorter-termresearch activity areas. The resultingconsensus mission plan and goals,objectives, and research activitiesserve as the nucleus for the currentStrategic Plan.

A draft of this Plan was provided tothe Space Studies Board and its

committees for review and feed-back, and guidance received wasused in finalizing the Plan. Thefindings and recommendations ofthe Academy’s recently completedten-year astronomy and astro-physics survey were consulted toassure consistency with the draftPlan. Finally, the Space ScienceAdvisory Committee had an oppor-tunity to review the revised Planand suggest any final changes beforethe Plan went to press.

Tactical Planning and Budgeting

Congress appropriates funding toNASA for its programs on a yearlybasis. While each Administration-submitted budget provides a five-year profile for the Agency’sprograms, only the first is imple-mented each year by Congress.Somewhat more than a year beforethe beginning of a fiscal year, the

Enterprise assembles a detailedbudget proposal for submissionto the Agency Administrator.Preparation of this budget, whilebased on the Enterprise StrategicPlan, is also guided by the previousyear’s budget estimate for the newyear, policies and guidance provid-ed by the Administrator and theOMB, and the current budget andtechnical status of missions in devel-opment or operating. Ongoing pro-gram balance and technologyreadiness are also considered. AGPRA performance plan for thesame fiscal year is assembled inparallel with the new Enterprisebudget request. Twelve monthsbefore the beginning of the newfiscal year, both the Agency budg-et and its GPRA performance planare submitted to the OMB, andafter a period of negotiations andadjustments, the President sub-mits NASA’s budget request withthose of other Federal agencies toCongress for action.


Government Performance and Results Act of 1993 (GPRA)

This legislation requires each Federal agency to periodically develop and deliver to Congress threedocuments:

• A strategic plan that presents goals and objectives over a five year period; this plan must berevised at least every three years;

• A yearly performance plan that projects which measurable outcomes that support goals andobjectives of the strategic plan will occur during the upcoming fiscal year; the performance plan isto be closely coordinated with the requested budget; and

• A yearly performance report, to be delivered six months after the end of the fiscal year in question,that summarizes the agency’s achievements against projections in that fiscal year’s performance plan.


Here we present missions that we expect to graduate from the study and design

phase and begin building in 2003 and beyond. We have grouped these projects

to show how they address our science objectives. While the section mentions for

context some of the missions that will already be under development or flying by

2003, those that will proceed from study and preliminary design to implementa-

tion (detailed design and fabrication) beginning in 2003 are named in bold when

they are first mentioned under each objective. Note, however, that although many

of our missions address more than one science objective, no effort has been

made to mention every mission in every connection in which it can make a

contribution.

50

f l i gh t p rog ram: 2003 andSection II-3Section II-3

This section emphasizes mis-sions that will begin implemen-tation in the period 2003-2007.Planning for the period 2008through the following decade isnecessarily less certain. The endof each subsection also presentsideas for missions in this moreremote timeframe based on rea-sonable extrapolations from ourcurrent scientific understandingand nearer-term mission plans.These future mission concepts arealso introduced in bold in theirpart of each subsection.

OBJECTIVE ONE:Understand the structureof the universe, from itsearliest beginnings to itsultimate fate

The universe we see today is richin structure, containing hundredsof billions of galaxies, each withhundreds of billions of stars.Clusters and super-clusters ofgalaxies are interspersed with vast,virtually empty voids, and thegalaxies themselves can appear

totally isolated or in the process ofmerging with local companions.Yet observations to date of the veryearly universe show it to have beenvery smooth and almost feature-less. How did the later structure,the basic extragalactic buildingblocks of the universe, come tobe? What laws of physics workedto fill the gap between the primi-tive universe and the complexitywe observe in the present?

With the Cosmic BackgroundExplorer (COBE), we have cap-

flight program: 2003 and beyond | 51

d beyond

Detailed analysis of the cosmic

microwave background can deter-

mine the geometry of the universe

to high precision and shed light on

the nature of the matter and energy

that fill the universe. BOOMERANG

observed this background over

approximately 2.5 percent of the

sky with angular resolution 35 times

finer than COBE, and MAP and

Planck will continue to extend and

refine these measurements.

tured a glimmer of the earliestclumpings in the remnant pri-mordial fireball through ripples intoday’s pervasive microwave back-ground. Balloon-borne instru-ments such as BOOMERANGmap a small portion of the cosmicmicrowave background radiation,the fossil remnant of the BigBang. The Microwave AnisotropyProbe (MAP) Explorer and theESA/NASA Planck mission willextend these measurements andpermit precise determination of a

number of critical cosmologicalparameters that constrain modelsof the early universe.

But there is a missing link betweenthe first condensations of matterafter the Big Bang and the galaxiesand clusters we see in the present.With the ability to identify the darkmatter and learn how it shapes thegalaxies and systems of galaxies, wewill begin to determine the size,shape, and energy content of theuniverse. Ground-based surveys

such as the Two Micron All SkySurvey (2MASS), Sloan Digital SkySurvey (SDSS), and Explorer-classspace missions will provide aninventory of low-mass objects in theneighborhood of the Sun. Mass inthe gaseous state will be studied at avariety of wavelengths, correspon-ding to the temperature of the gas.These range from millimeter wavesobserved by ground-based interfer-ometers to the x-rays from hot clus-ter gas seen by the Chandra X-rayObservatory (CXO).

An important advance will be toestimate the total mass in galaxies,clusters of galaxies, and even innon-luminous, dense regions bymeasuring the gravitational bend-ing of light from background galax-ies. Observing this “gravitationallensing” is among many motiva-tions for the Next GenerationSpace Telescope (NGST), alongwith investigating the birth of galax-ies, the fundamental structures ofthe universe. These observationsmust be made at near-infraredwavelengths and require a telescopewith a large aperture (for sensitivityto faint objects), excellent angularresolution, and the stable images ofa space observatory.

The evolution of the universe willalso be probed by Constellation-X,the x-ray equivalent of a verylarge optical telescope. It willimprove significantly on the spec-tral information returned by the


The Constellation-X spacecraft will work in unison to simultaneously observe

the same distant objects. By combining their data, these satellites become 100

times more powerful than any previous single x-ray telescope.

current ESA X-ray Multi-MirrorMission (XMM) and comple-ment the high spatial resolutionof CXO. Constellation-X willexplore the epoch of formation ofclusters of galaxies and how theyevolve. The mission will traceblack hole evolution with cosmictime and provide new insightinto the contribution that theaccretion of matter around blackholes and other compact objectsmakes to the total energy outputof the universe. Technologicaladvances that will be needed forConstellation-X are under devel-opment: x-ray optics, x-raycalorimetry, reflection gratings,detectors for high-energy x-rays,

cryogenic coolers, and focusingoptics for hard x-rays.

For Possible Implementation After 2007

The very highest energy cosmicrays are extremely rare, and a hugedetector would be needed toobserve any significant number ofthem. Earth’s atmosphere, withmillions of square kilometers ofexposed area and an interactiontarget up to 1013 tons, can act as agiant detector for the extreme ener-gy cosmic rays and neutrinos. Wedo not know where these particlescome from or how they are acceler-

ated. It has been suggested thatthey might come from the annihi-lation of space-time defects formedat the beginning of the universe, soobserving these mysterious parti-cles with an orbiting wide-anglelight collector could probe the BigBang itself.

Beyond 2007, expected advancesin detectors, interferometry, light-weight optics and cryogenics willallow a mission that can extendthe Hubble Space Telescope-like(HST) resolution into the mid-and far-infrared to resolve theinfrared background and to learnthe history of energy generationand chemical element formation


Cosmic Journeys

The new Cosmic Journeys initiative is a series of major astrophysics observatories that will addressaspects of three Enterprise science objectives:

• Understand the structure of the universe, from its earliest beginnings to its ultimate fate;• Explore the ultimate limits of gravity and energy in the universe; and• Learn how galaxies, stars, and planets form, interact, and evolve.

Beyond the fundamental scientific importance of these goals, can we discover new physics that wecould use? For example, to send machines or people beyond our Solar System to even the neareststar at today’s fastest speeds would take tens of thousands of years. As a result, we are particularlyinterested in the physics of these extreme phenomena:

• The source of cosmic gamma ray bursts;• The acceleration of ultra-high energy cosmic rays;• Energetics of black holes; and• Gravitational waves: whether they exist, and whether they travel at the speed of light.

in the universe. A pathfinder mis-sion using one of two alternatetechnologies would provide muchgreater angular resolution thanthat of the Space Infrared Teles-cope Facility (SIRTF), as well asbetter sensitivity and signal-to-noise. This descendant of theHST, discussed further in connec-tion with Objective Three, couldbe either a space infrared interfer-ometric telescope or a filled-aper-ture infrared telescope. Technicalrequirements on the mirrors forsuch an instrument are challenging,but the necessary capabilities mayevolve from earlier development forthe NGST and the TerrestrialPlanet Finder (Objective Four).

Measuring the cosmic microwavebackground polarization couldprovide an important test of theinflation theory, possibly detectingcosmological background gravita-tional waves produced when theuniverse was much less than a sec-ond old.

OBJECTIVE TWO:Explore the ultimate limits of gravity andenergy in the universe

Cosmic rays, whose origin has longbeen a mystery, are important trac-ers of the dynamics and structureof our galaxy. The magnetic fieldsand shock structures with which

cosmic rays interact along theirjourney are not directly visible to us,so we must study these fields andstructures by detailed measurementof the arriving particles themselves.We currently believe that most cos-mic rays are accelerated by theshock fronts produced by super-novae. The Advanced Cosmic RayComposition Experiment for theSpace Station (ACCESS) is beingdesigned to explore this connec-tion of cosmic rays with super-novae. ACCESS will have thesensitivity needed to study cosmicrays up to the highest energiesbelieved achievable by supernovashock acceleration, and will enableus to analyze their compositionand thus address the origin, accel-

eration, and ultimate fate of theindividual nuclei, from hydrogento iron and heavier ions. ACCESSwill require a number of techno-logical advances. For the chargedparticle detectors and calorimeter,silicon pixel detectors with a largedynamic range readout and goodspatial resolution will be needed.Advances are also needed in read-out electronics for gas-filled detec-tor tubes used in the transitionradiation detectors.

Do gravitational waves exist, andwhat is the structure of space-timenear black holes? Complementingthe ground-based gravitationalwave detectors that will becomeoperational within the next few


ACCESS instrument mounted on the International Space Station will explore

the connection of cosmic rays with supernovae.

years, the Laser InterferometerSpace Antenna (LISA) will be ableto observe low-frequency gravita-tional waves not detectable fromthe ground. A joint NASA-ESAundertaking, LISA will search forgravitational waves from massiveobjects, ranging from the very earlyuniverse before light could propa-gate, to super-massive black holesin the centers of galaxies, as well asshort-period compact binary starsin the Milky Way. Three key tech-nologies are needed to make LISA areality. First, the experiment willrequire inertial sensors whose proofmasses can be isolated from allforces other than gravitation.Micro-thrusters must keep each ofLISA’s three independent spacecraftcentered on its proof mass. Then,to measure the motions of the iso-

lated and widely separated proofmasses, laser metrology to measuresubpicometer changes betweenthem is needed.

Constellation-X observations ofbroadened x-ray emission lines ofiron in active galactic nuclei willmeasure black hole masses andspin, on the basis of relativisticeffects that occur in the limit ofvery strong gravity fields.


The key to understanding how con-densed objects like quasars and pul-sars work is to obtain more detailedobservations of them. By using anorbiting telescope as part of a space

very long baseline interferometer(SVLBI), radio astronomy canachieve resolutions of about 25microarcseconds. Such a missioncould show us how matter is accret-ed onto black holes, how relativisticjets of matter are formed, and howgamma rays are produced near blackholes. SVLBI can also investigatestellar evolution and the interstellarmedium through observations ofmasers, pulsars, and close binarystellar systems. Among technicalinnovations in amplifiers and cool-ers, such a system would requirevery fast (gigabits per second) down-link communications to Earth.

Beyond this, the prize is to directlyimage a black hole, whose existenceheretofore has been based on indi-rect evidence. This will require about


The Chandra x-ray image of Pictor A shows a spectacular jet that emanates from the center of the galaxy (left), probably

a black hole, and extends across 360 thousand light-years toward a brilliant hot spot (right). The hot spot is thought to be

the advancing head of the jet, which brightens where it plows into the tenuous gas of intergalactic space. By observing

dramatic phenomena like this spectroscopically, Constellation-X will enable us to unravel their underlying physical causes.

0.1 microarcsecond resolution, oralmost ten million times better thanCXO, which is itself about a factorof ten improvement over the earlierEinstein observatory. This is a tech-nology leap that cannot be achievedin one step, so the plan is to focuson a mid-term mission as an inter-mediate step to this goal. Thestrawman configuration for amicroarcsecond x-ray imagingmission pathfinder is a workinginterferometer with 100 microarc-second resolution and about 100cm2 effective area. This would pro-vide a substantial advance in scien-tific capability of its own, and allowus to detect and resolve an accre-tion disk around the massive blackhole at the center of the Milky Way.It would also give us detailedimages of jets, outflows, and broad-line regions in bright active galaxynuclei, and to map the center ofcooling flows in clusters of galaxies.The technology development forthis investigation involves primarilymatters of scale. The detectorswould build upon both theConstellation-X micro-calorimeterand the CCD’s designed for CXO,but with much larger arrays.Approaches to the technology forx-ray interferometry have beendemonstrated in the laboratory.

A high-resolution x-ray spec-troscopy mission (see ObjectiveThree) would provide diagnosticsof supernova mechanisms and anew view of accreting neutron stars

and black holes in our galaxy, aswell as the local group of galaxies.

The only full-sky survey we have inhigh energy x-rays dates from1979. Observations of these hardx-ray emissions are key to studyingaccreting neutron stars, galacticblack holes, active galaxies, andcreation of the chemical elements.The needed x-ray observations inthe 10-500 KeV range could beacquired by a proposed energeticx-ray imaging survey telescope.

As described in the previous sec-tion, an orbiting wide-anglelight collector would enable us toobserve the very highest energycosmic rays. Observing these mys-terious particles would be aninvestigation of the highest energyprocesses in the universe and aprobe of the Big Bang within theframework of Grand UnifiedTheories of fundamental physics.

OBJECTIVE THREE: Understand how galaxies, stars, and planets form, interact, and evolve

One of our fundamental sciencegoals is to understand how structurefirst arose in the extremely densebut featureless early uni-verse.Images that show that galaxieslooked very different billions of

years ago from our familiar modernuniverse are clues to the linkbetween the first condensations ofmatter after the Big Bang and thegalaxies and clusters of galaxies wesee today. The HST has shown thatafter galaxies form, they can beobserved colliding with one anotheror being badly disrupted. SIRTFwill expand on these investigationsby studying the evolution of themost energetic galaxies. But theseimportant observations will not fullyanswer the core question of howgalaxies—the fundamental buildingblocks of the universe —originated.

The HST’s aperture is too small togather enough faint light from theremote past to detect galaxies in theprocess of formation. To do so, wewill need observations at near-infrared wavelengths from a tele-scope with a larger aperture (toprovide sensitivity to faint objects)and superb angular resolution (toobserve structure in distantobjects)—the Next Generation


One possible concept for an NGST

design, showing the telescope

beneath a large Sun shade.

Space Telescope (NGST). First ofthe Origins Observatories, NGSTwill have about ten times the light-collecting area of HST and will bemost sensitive at the infrared wave-lengths where galaxies being bornare expected to be brightest. Also,although the HST and ground-based observatories have revealedmuch about the formation of stars

and their potential retinues of plan-ets—and SIRTF and SOFIA willreveal much more—essentialprocesses and events in the earlylives of stars and planets are poorlyknown. Very young stars, as well asplanets in the process of formation,will be important targets forNGST’s powerful infrared instru-ments. When stars are first born,

they are cocooned in the dusty gasclouds from which they formed.This dust very effectively absorbsvisible light but emits copiousinfrared radiation. NGST will beable to peer into the clouds inwhich the youngest stars and plan-ets are found, and will reveal theirlocation, mass, chemical composi-tion, and dynamics. (As an exam-ple of scientific synergy, Cassini’sobservations of Saturn’s rings willhelp us interpret observations ofthese clouds by providing a close-up view of the behavior of dust,ice, and magnetic fields in a rela-tively nearby setting.) To achieveNGST’s demanding scientificgoals, we are developing very light-weight optical structures, new gen-erations of infrared detectors,energy-efficient cooling tech-niques, and precision deployablestructures.

NGST observations will be complemented by data from theESA/NASA Far Infrared andSubmillimeter Telescope (FIRST).Observing at longer wavelengthswhere many galaxies emit most oftheir radiation, FIRST will bewell suited to finding high red-shift galaxies and studying themost luminous galaxies, comple-menting NGST’s searches in thenear-infrared. The ESA-led INTE-GRAL gamma ray mission will besupplying information on stellarformation via both high-energyspectroscopy and imaging.


An image of the darkest portion of the sky reveals the structure of young galax-

ies at cosmological distances, as shown by the near infrared camera (NICMOS)

on the Hubble Space Telescope. Some of the reddest and faintest objects may

be over 12 billion light-years away.

The Space InterferometryMission (SIM) will serve impor-tant objectives in both technolo-gy and science. For technology,it will demonstrate precisionmetrology and aperture synthe-sis imaging, both vital for futureoptical space interferometermissions. Its science contribu-tions stem from its anticipatedtiny positional error circle forobserved objects, only fourmicro-arcseconds; this is about100 times better than theHipparcos astrometry mission.This precision will make SIM apowerful tool for studying thedistances, dynamics, and evolu-tion of star clusters in ourgalaxy, helping us understandhow stars and our galaxy wereformed and will evolve. It willextend our census of nearby plan-etary systems into the range ofsmall, rocky planets for the firsttime. SIM will also improve thecalibration of luminosities ofstandard stellar distance indica-tors to enable us to more accu-rately measure distances in theuniverse.

The Terrestrial Planet FInder(TPR) (see Objective Four) willbuild on these missions toextend our understanding ofplanetary systems.

With a hundred-fold increase insensitivity for high resolutionspectroscopy over previous obser-

vatories, Constellation-X willlook across a broad range of red-shifts to date the formation ofclusters of galaxies. Matter predict-ed by Big Bang creation and sub-sequent stellar processing seems tobe missing, and Constellation-Xwill search for it in the hot, metal-enriched intergalactic medium.Constellation-X will also be ableto analyze the chemical composi-tion of stellar coronae, supernovaremnants, and the interstellarmedium by observing x-ray spec-tral lines.

For Possible ImplementationAfter 2007

An exciting new approach tostudying the origin of the chem-ical elements (nucleosynthesis)is embodied in a concept for ahigh-resolution x-ray spec-troscopy mission, which wouldenable sensitive spectroscopicand imaging observations ofemitted radiation related tonucleosynthesis. Many of thesespectral features lie in the hard x-ray range. Observations of thespectra of young supernova rem-nants, and studies of the time-evolution of prompt emissionsfrom recent explosions, wouldprovide diagnostics on the pro-duction and distribution ofheavy elements, and on theexplosion mechanism itself. Sucha mission would also providesensitive spectral studies of active

galaxies and measurements ofmagnetic field strengths ingalaxy clusters. Technologydevelopment is needed for boththe optics and the focal planesensors. More complex multilay-ers will be needed to extendinstrument response to the 200KeV region. Germanium sensorswill need the development ofcontact technologies and verylarge scale integration readoutelectronics operable at cryogenictemperatures.

An x-ray interferometry pathfind-er system, such as the onedescribed for Objective Twoabove, would add importantly toour knowledge of stellar struc-ture, stellar plasma interactions,jets and outflows from activegalactic nuclei, cooling flows inclusters of galaxies, as well aslocate and resolve star formationregions.

Within our own galaxy, we are atthe brink of understanding howplanetary systems form. We haveobtained spectacular images ofstellar nurseries, and possibly ofdust disks in the process of creat-ing new planetary systems. We arebeginning to peer more deeplyinto dusty clouds to identify theyoungest members of new stellarclusters and probe the structureand basic physical properties ofstar forming regions. A filled-aperture infrared telescope,


which would also serve ObjectiveOne above, would determinehow planetary system-formingdisks evolve. With its keeninfrared vision, it would probedeeper into protostellar disks andjets to investigate the physicalprocesses that govern their for-mation, evolution, and dissipa-tion, as well as those thatdetermine their temperature,density, and compositional struc-ture. As outlined above, a com-peting concept with the samescience goals would be a spaceinfrared interferometric tele-scope, whose high sensitivity,spectral, and angular resolutionwould allow the far infraredbackground to be resolvedalmost completely into individ-ual sources. Major technologydevelopment for both is neededin the areas of ultra-lightweight

aperture technology, active sens-ing wavefront control, passiveand active cooling, and enablingdetector technologies. Thesetechnologies will build upon theones developed for precedingmissions such as NGST, SIRTF,and the Terrestrial Planet Finder.

Once the NGST has given us anunderstanding of the formationof the first galaxies in the earlyuniverse, we will be challengedto trace galaxy evolution back tothe initial era of star formation,super-massive black holes, andmetal element production in thepresent epoch. Capable of highresolution ultraviolet spec-troscopy at a sensitivity a hun-dred times that of the HST, afollow-on space ultravioletoptical telescope would enableastronomers to follow the chem-

ical evolution of the universe anddetermine its fate. Tracing thedistribution of visible matterwould make it possible to quanti-fy the birth rate of galaxies andthe energetics of quasars. Itmight also shed light on the dis-tribution of the underlying darkmatter.

Ultimately, we would like tomake in situ measurements ofmatter and magnetic fields out-side the bubble of space filled bythe Sun’s solar wind. An inter-stellar probe mission wouldexplore the structure of theheliosphere and go on to samplematter and magnetic fields inthe interstellar medium directly,for the first time. To travel thisdistance in just two decades willrequire a new approach topropulsion, perhaps solar sails.


Origins Observatories

The Origins Observatories are a series of astronomical telescopes in which each successive missionbuilds on the technological and scientific capabilities of previous ones. The vision is to observe thebirth of the earliest galaxies in the universe, to detect all planetary systems in the solar neighbor-hood, and to find those planets that are capable of supporting life. To achieve this vision, the OriginsObservatories line includes these components:

• A series of spectroscopic, imaging, interferometric missions, observing at visual and infraredwavelengths to answer the vision’s fundamental scientific questions.

• A systematic technology development program in which technology enabling one mission leadsnaturally into the technology needed for the next one.

• Basic research to understand new observations.• A comprehensive education and public outreach effort.

OBJECTIVE FOUR:Look for signs of life inother planetary systems

Determining whether habitable orlife-bearing planets exist aroundnearby stars is a fundamentalEnterprise goal. In addition,learning about other nearby plan-etary systems will provide pre-cious context for research on theorigin and evolution of our ownSolar System. By measuring thevelocity variation of a star’smotion caused by the gravitation-al effect of unseen companions,ground-based observations haverevealed dozens of circumstellarobjects in the solar neighborhoodthat are much less massive thanstars, but still far heavier thanEarth. It is not certain, however,that the objects so far discoveredare “planets” as we usually thinkof them, and new generations ofmissions will be required to dis-cover orbiting objects that aremore like Earth.

In 2003, several important proj-ects that promise to detect planetssubstantially lower in mass thanthose known today will be nearingoperation. These include the KeckInterferometer and the Full-skyAstrometric Mapping Explorer(FAME) mission.

While detecting the presence ofEarth-mass planets is an impor-

tant objective, determining theirkey characteristics—above all, thepossibility of life—is much moredifficult. Astrobiology research isdeveloping a working catalogue ofpossible atmospheric signaturesthat would be indicative of life ona planetary scale. For example,today’s Earth is recognizable as liv-ing primarily because of its oxy-genated atmosphere, but this wasnot always the case. Astrobiologyis seeking to discover what Earth’sbiosignature would have looked

like at a time when free oxygenwas negligible and other biogenicproducts would have been presentin atmosphere.

Looking outside the SolarSystem, the discovery of numer-ous low-mass “non-stellar” bodiesorbiting other stars is challengingour understanding of planet formation and implying thatplanetary systems may be com-monplace. With our Solar Systemas a model for the propensity for


The atmospheric infrared spectra of Venus, Earth, and Mars all show a domi-

nant carbon dioxide feature. In addition, Earth's spectrum exhibits water and

ozone—the simultaneous presence of all three gases indicates a living planet.

life, we can conjecture that thereare other worlds in our galacticneighborhood capable of sup-porting life. Our exploration ofthe diversity of planetary systemsaround other stars will emphasizesystems that may have character-istics necessary for life. In addi-tional to contributing to ourknowledge of the structure anddynamics of our galaxy, SIM,described under Objective Three,will be the first observatory capa-ble of indirectly detecting plane-tary bodies with only a fewtimes the mass of Earth inorbit around other stars.

Continuing the Origins Observa-tories line, the Terrestrial PlanetFinder (TPF) will extend thesearch for signatures of life beyondour Solar System. TPF will be aninterferometric telescope array thatwill separate the infrared light of aplanet from that of the star that itorbits in order to measure the spec-trum of the planet. It will be ableto search about 200 nearby starsfor planets that possess warmatmospheres containing significantamounts of water or oxygen, whichwould indicate the possible pres-ence of biological activity of somekind. To do so, the design for TPF

will build upon large aperture,cryogenic optics, and infrareddetector technologies also neededfor the NGST, the beam controland nulling capabilities of theground-based Keck Interferometerand SIM, and the precision free-flying demonstration of the SpaceTechnology-3 (ST-3) mission.

For Possible ImplementationAfter 2007

The first decade of the new mil-lennium should have yielded tan-talizing clues about the nature ofthe planets in the solar neighbor-


Left: The Space Technology-3 (ST-3) mission will test new technologies by flying two spacecraft in formation and using

laser beams to keep the spacecraft aligned in precise positions relative to each other.

Right: By combining the high sensitivity of space telescopes with the high resolution of an interferometer, TPF will be able

to reduce the glare of parent stars by a factor of more than one hundred-thousand to see planetary systems as far away

as 50 light-years. TPF’s spectroscopy will allow atmospheric chemists and biologists to analyze the relative amounts of

gases like carbon dioxide, water vapor, ozone, and methane to ascertain whether a planet might support life.

hood, and about the presence—orabsence—of life there. However,the TPF will be only the first steptoward a detailed understandingof planetary systems in our neigh-borhood. The modest collectingarea of the elements of TPF willpermit only the first reconnais-sance of these systems. The nextstep in studying other planetarysystems will be observatories withsignificantly larger apertures andwider wavelength coverage.

The sensitivity of astronomicalobservatories depends strongly onthe size of the light-collectingaperture, so that much larger suc-cessors to TPF would be able toobserve far more target systemsand search for rarer chemicalspecies in planetary atmospheres.This will allow a less ambiguousinterpretation of planetary spectraand permit a much wider range ofplanetary types to be observed. Twoconcepts on the horizon are a spec-troscopic mission, a “life finder,”and later, a complementary “planetimager.” The prize from this newgeneration of observatories wouldbe a truly comprehensive pictureof planetary systems, includingtheir physical characteristics andmore conclusive signatures of lifeoutside our Solar System. Thesemissions to follow TPF willdepend on even more ambitiousoptical systems, in particular, mir-rors tens of meters in diameter.Since current space telescope tech-

nologies appear limited to smallercollecting areas, large optical sys-tems technology will continue tohave high priority for the SpaceScience Enterprise. Astronaut-assisted deployment or position-ing approaches might be of greatvalue in assembling and operatingthese future observatories, andadvanced remotely-supervisedrobotic systems may also be avail-able in that time frame.

OBJECTIVE FIVE: Understand the formation and evolutionof the Solar System andEarth within it

Earth and all of the other bodies inthe Solar System formed at aboutthe same time from the same reser-voir of material—a disk of gas anddust encircling the early Sun. Thesebodies have similarities, but alsoexhibit striking differences. Forexample, Jupiter and Saturn bothhave massive hydrogen-heliumatmospheres apparently surround-ing ice and rock cores, whileUranus and Neptune are mostlylarge ice and rock cores with muchless surrounding gas. All of theseouter planets, in turn, differ dra-matically from Earth and the other“rocky” bodies that inhabit theinner Solar System. What were thedifferences in formation and evolu-tion that led to these and other

striking differences among thediverse bodies of the Solar System?

Looking more closely at the innerplanets, we see that they are simi-lar in size, but differ dramaticallyfrom one another in their atmos-pheres and surface properties. Webelieve that these rocky planetsprobably shared common originsbut followed very different pathsto the present. What evolution-ary processes account for thesedifferences? Are these processesstill at work, and what do theyimply about our future on Earth?

Superficially so different fromEarth, Mars appears to have beenmuch more Earthlike earlier in itshistory. One of the major objec-tives of the Mars ExplorationProgram (MEP) is to trace theevolutionary history of our neigh-bor planet. The Mars scientificcommunity has adopted a "seek,in situ, sample" approach thatemploys surface and orbital recon-naissance to gain an understand-ing of the planet that will lead tomultiple sample returns. To sup-port this strategy, high-resolutionorbital imaging will follow up onMars Global Surveyor results thatsuggest the presence of near-sur-face water in recent times.Increasingly advanced landers willbe interspersed with these orbitalmissions. One aspect of the pro-gram approach is to establish highbandwidth data return capabilities


to support the “seek, in situ, sam-ple” approach.

Key capabilities for near-termMars missions include precisionguidance and landing, surfacehazard avoidance or tolerance,surface and atmospheric mobili-ty, and aero-entry systems. Aero-capture would reduce propellantrequirements. We need advancesin systems for in situ analysis ofmaterials that can help guide theselection of the small samplesthat we will be able to return.Sample return missions will also

require development of high-specific thrust, compact ascentpropulsion systems. A variety ofadvanced information system andcommunications technologies,including autonomy, inter-space-craft communication systems, andoptical communications, will beapplied to future missions.

Valuable information about theearly history of the Solar Systemresides at its boundaries. A Pluto-Kuiper Express mission wouldcarry out the first reconnaissanceof the last planet not visited by

spacecraft and scout the inneredge of the Kuiper Belt. Plutoand its large satellite Charon rep-resent a poorly understood class ofremote and icy dwarf planets. TheKuiper Belt is a flattened disk oficy debris, believed to be in aprimitive state, remaining fromthe processes that formed themajor planets in our Solar System.

Other candidate missions in theOuter Planets Program to followthe Europa Orbiter include theTitan Explorer and EuropaLander. These missions would


Left: High-resolution images from the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) suggest that liquid water

has seeped onto the surface in the geologically recent past.

Right: The surface of Pluto is resolved in these Hubble Space Telescope pictures. These images show that Pluto is an

unusually complex object, with more large-scale contrast than any planet besides Earth. Variations across Pluto’s surface

may be caused by topographic features such as basins or fresh impact craters. However, most of the surface features,

including the northern polar cap, are likely produced by a distribution of frosts and chemical byproducts.

build on the results from preced-ing missions to conduct in-depthanalyses of these icy, organic-rich environments to determinewhether they hold the possibili-ty of life. Mission sequence deci-sions will be based on continuingscientific discoveries and theprogress of our technology pro-grams. For example, excitingresults from the Cassini-Huygensmission arriving in the Saturn sys-tem in 2004 might advance the

Titan Explorer ahead of othermissions under study.

Highly capable, autonomousmicro-avionics and very efficienton-board power subsystems are keyto all future outer planetary mis-sions. Multi-megarad radiation tol-erance is a stringent requirement forall missions that operate in theJovian environment. Avionics tech-nologies projected for readiness in2003 could support the Europa

missions, while further advanceswill be required for the TitanExplorer. The Titan mission willrely on advanced solar electricpropulsion and aerocapture. Specialrequirements for Europa Landerreadiness include progress inbioload reduction and advancedchemical propulsion for landing onthis massive airless body.

The so-called primitive bodies,comets and asteroids, containimportant clues to the early historyof the Solar System. It is hypothe-sized that comets and asteroids werethe fundamental “building blocks”of planet formation and that most ofthese bodies that we see today arethe debris left over from this process.Impacts on Earth by comets mayhave delivered the materials neededfor the origin of life here: water,atmospheric gases, and perhapsorganic chemicals. The Deep Impactmission, which will advance the


Outer Planets Program

Exploration of the outer Solar System has revealed that the outer planets and their moons are rich in organ-ic material, that subsurface liquid water may exist in some places, and that prebiotic chemical processesoccur in some of these environments. The Galileo spacecraft has returned fascinating information aboutthe moon Europa. The Cassini-Huygens mission, now en route to Saturn, will extend this explorationthrough intensive investigations of the organic-rich atmosphere and surface of Saturn’s giant moon, Titan.

Continuing this exploration thrust, the Outer Planets program will focus on prebiotic chemistry in likely placesin the outer Solar System. Mission sequence decisions will be based on ongoing scientific discoveries andtechnological progress. Destinations for missions in this line include returns to Europa and Titan, reconnais-sance of the Kuiper Belt, and a more comprehensive study of the Neptune system, including its moon Triton.

Artist’s concept: The Cassini spacecraft flies by with its high gain antenna

pointed at ESA’s Huygens probe as it reaches the surface of Titan. Saturn is

dimly visible in the background through Titan’s thick atmosphere of methane,

ethane, and (mostly) nitrogen. Cassini is a joint mission of NASA, the European

Space Agency, and the Italian Space Agency.

study of the composition of primi-tive bodies pioneered by earlier mis-sions to Halley’s comet, will belaunched in mid-decade. To take thenext step, a Comet Nucleus SampleReturn is a high priority new imple-mentation start to complementongoing Solar System explorationprograms. The goal of this mission,which could initiate a new “ToBuild a Planet” mission line, is toreturn a pristine sample of materialfrom a comet nucleus for detailedchemical analysis. The CometNucleus Sample Return will dependon micro-avionics, advanced com-puting, and spacecraft autonomytechnologies that are currently beingdeveloped. Advances in solar electricpropulsion that focus on increasedlifetime and reliability are needed.Other key capabilities include anEarth-entry system that can survivevery large entry speeds into ouratmosphere.


According to current planning,the Europa Orbiter, Pluto-KuiperExpress, Titan Explorer, and EuropaLander could be followed withinthe Outer Planets line by aNeptune orbiter. This mission is animportant component of our inves-tigation of the outer Solar System,including Neptune’s moon, Triton,which may be an icy, organic-rich,captured Kuiper Belt object.

A number of other exciting oppor-tunities are being considered forimplementation as follow-ons inthe “To Build a Planet” line after2007. For example: so Earth-like insome respects, but so alien in others,Venus presents a genuine puzzle.Why did a planet with strikinglyEarth-like size, composition, andgeological activity develop a radical-ly different surface and atmosphericenvironment? Understanding thisevolutionary divergence has impor-tant implications for the study oflife-sustaining environments as well

as for our understanding of Earth’sfragile, changing environment. AVenus surface sample return mis-sion would help us to answer fun-damental questions about theevolution of Earth-like planets.

Understanding the behavior of gas,dust, and radiation together is animportant key to understanding theformation of the Solar System. Insome ways, the rings of Saturn con-stitute a laboratory for the behaviorof uncoalesced material in the prim-itive solar nebula. A Saturn ring


The composition and physical and chemical processes of comets are key to

unlocking the secrets of the early Solar System. This dramatic pioneering

image of the nucleus of Halley’s Comet was obtained by the ESA Giotto space-

craft in March 1985.

observer mission could performdetailed investigations of complexdynamic processes in Saturn’s rings.In effect, we would be able to peerback in time to the epoch of plane-tary formation, when the materialnow contained in the planets wasspread out in a disk encircling theSun. It would also provide critical“ground truth” for a variety ofobservational and theoretical astro-physical studies. The Venus andSaturn ring missions would contin-ue the “To Build a Planet” line.

The Mars Exploration Programwill continue its search for evidenceof water, the quintessential ingredi-ent for life. A Mars synthetic aper-ture radar orbiter mission coulddetect buried water channels andhelp direct our search for ancientand modern water reservoirs.Advanced missions that could fol-low initial sample return missionscould drill deeply (perhaps 10 to100 meters) into the Martian

cryosphere and hydrosphere to fol-low up results from earlier samplereturn missions. Surface, subsur-face, orbiting, and airborne ele-ments would extend our ability tocarry out wide-area exploration andsampling in three dimensions. Far-term missions will require many ofthe technology advances that will bedeveloped for the nearer-term, aswell as further progress in the areasof thermal control, inflatables, aero-braking, precision landing, autono-my, advanced electric propulsion,advanced power systems, opticalguidance, and control.

Other mission candidates for laterimplementation include a Jupiterpolar orbiter for long-term detailedinvestigations of Jupiter’s interior,atmosphere, and magnetosphere;giant planet deep probes to meas-ure bulk composition, chemicalprocesses, and atmospheric dynam-ics of the giant planets; a lunar giantbasin sample return to collect sam-

ples from a very old impact basin farfrom previously sampled sites onthe Moon; and a multiple asteroidmission/protoplanet explorer toinvestigate the relationship of main-belt asteroids to planetary evolu-tion. As technological progresscontinues, some of these missionscome within the scope of theDiscovery program.

OBJECTIVE SIX:Probe the origin andevolution of life on Earthand determine if lifeexists elsewhere in ourSolar System

NASA research on the origin, evo-lution, and distribution of life inthe universe is focused on tracingthe pathways of the biologicallycritical elements from the originof the universe through the majorepochs in the evolution of living


To Build a Planet

An understanding of the formation and development of planets and their environments is a crucial miss-ing link in our understanding of the Solar System and the development of life. At this juncture, we havelearned enough to frame this subject in terms of three fundamental questions:

• What are the building blocks of which planets are made?• What dynamic processes are involved in the initial formation of planets and planetary systems?• What determines the diverse outcomes of planetary formation and evolution?

Answers to these questions are accessible to us in present-day Solar System objects: comets andasteroids, planetary rings, and the planets themselves.

systems. To understand the possi-bilities for life, we need to studythe only known example, life hereon Earth. NASA has made majorcontributions to discoveries in thisarea, such as the recognition thatlife began very early in Earth’s his-tory (3.85 billion years ago) andthat our earliest microbial ancestormay have been a heat-loving,hydrogen-utilizing microbe. Majorchanges in the evolution of lifehave been tied to biological andgeological processes (for example,the oxygenation of our atmos-phere) and to extraterrestrial eventssuch as an asteroid impact 65 mil-lion years ago that ended the age ofthe dinosaurs. Stellar evolutionmodels suggesting that the Sun wasmuch fainter at the time life wasarising on Earth have called atten-tion to the influence of solar vari-


A computer-generated dynamic model of a primitive cell used to test theories

about the formation and behavior of Earth’s earliest life.

The Astrobiology Institute

The new science of astrobiology synthesizes many scientific disciplines—astronomy to biology,geology to ecology, chemistry to informatics. Scientists from these disciplines, working toward thecommon goal of discovering the thread of life in the universe, have developed an AstrobiologyRoadmap with three fundamental questions, ten goals, and 17 specific program objectives(http://astrobiology.arc.nasa.gov).

To pursue these goals and objectives, NASA has adopted an innovative approach to integrating effortsin these disparate disciplines by establishing the NASA Astrobiology Institute. The Institute advances ourknowledge by forming interdisciplinary teams of researchers to attack major questions across a broadscientific front. It is a “virtual institute,” in that it is a collaborative activity rather than a physical location.The members of these teams are geographically dispersed, but synthesize expertise in diverse fields bycoordinating research goals, by frequent personnel exchanges, and by ongoing series of workshops,seminars, and courses, supported by the Institute’s electronic networks.

ability on both the emergence andpersistence of life on Earth.

A new space science research andanalysis initiative, the AstrobiologyInitiative, will study life in the Uni-verse to determine how life beganand evolves, whether there is lifeelsewhere than on Earth, and whatthe future of life is, on Earth andpossibly beyond it. Understoodbroadly, the new field of astrobiolo-gy encompasses not only fundamen-tal biology, but also cosmochemistry,exobiology, evolutionary biology,

gravitational biology, and even ter-restrial environmental science andecology. At NASA, some elementsof this syncretic discipline fall intothe purview of other enterprises.But the space science programaddresses many of its most funda-mental issues.

While not strictly a mission, theAstrobiology Initiative is compara-ble in scope and ambition to amajor flight program. As a newresearch field, astrobiology intendsto expand exobiology research and

encompass areas of evolutionarybiology to further our understand-ing of how life may persist andevolve to exert a global environ-mental influence. One objective ofastrobiology is to reconstruct theconditions on early Earth that wererequired for the origin of life and todetermine the nature of processesthat govern the evolution of life.Two approaches to learn about lifeon early Earth are to investigate the geological record and to use the genetic record, contained incontemporary microorganisms, to


Goals of Astrobiology

Question: How does life begin and develop?

Goal 1: Understand how life arose on Earth.Goal 2: Determine the general principles governing the organization of matter into living systems.Goal 3: Explore how life evolves on the molecular, organism, and ecosystem levels.Goal 4: Determine how the terrestrial biosphere has co-evolved with Earth.

Question: Does life exist elsewhere in the universe?

Goal 5: Establish limits for life in environments that provide analogues for conditions on other worlds.Goal 6: Determine what makes a planet habitable and how common these worlds are in the

universe.Goal 7: Determine how to recognize the signature of life on other worlds.Goal 8: Determine whether there is (or once was) life elsewhere in our Solar System, particularly on

Mars and Europa.

Question: What is life’s future on Earth and beyond?

Goal 9: Determine how ecosystems respond to environmental change on time-scales relevant tohuman life on Earth.

Goal 10: Understand the response of terrestrial life to conditions in space or on other planets.

characterize traits of our microbialancestors. From an experimentalapproach, researchers will developand test pathways by which thecomponents of life assemble intoreplicating systems that can evolve.Current research is expanding ourunderstanding of the possibilitiesfor the earliest life, utilizing simplermolecules and systems that couldhave been the precursors to the pro-tein/RNA/DNA system used by alllife today. It is only recently that wehave been able to measure the scopeof biological diversity. We havefound that life thrives on Earthacross the widest range of environ-ments, inhabiting hydrothermalvents, extreme cold-deserts, envi-ronments at the limits of pH andsalinity, and rocks kilometersbeneath Earth’s surface. This infor-mation will give us clues to how lifemay have evolved and where itcould persist elsewhere.

In order to develop a complete pro-gram, the Astrobiology Initiative isbeing complemented by newthrusts in advanced concepts andtechnology. Elements already iden-tified are sample acquisition, prepa-ration, processing, and quarantine;hyperspectral remote sensing andimaging; in situ detection of life and“smartlabs;” detection and analysisof non-equilibrium thermochemi-cal states; extreme environmentsimulation chambers; biotechnolo-gy and bioinformatics; technologiesto access planetary surfaces and sub-surfaces; and next-generation planetimaging and analysis techniques.The intent is to identify specificareas in biotechnology, instrumen-tation, field studies, and missionswhere investment will significantlyadvance this new field.

Astrobiology is a major compo-nent of the Research and Analysis

Program (R&A, described atgreater length in section II-5). TheR&A program also supports theanalysis of primitive meteorites—and will extend this work toreturned samples from asteroidsand comets—to learn about theearly Solar System and the biolog-ic potential of planetary bodies.

Flight missions will also contributedirectly to the search for life or itsantecedents in the Solar System.Cassini, en route since 1997, willarrive at Saturn in 2004. ItsHuygens probe (provided by theEuropean Space Agency) willexplore the organic-rich atmos-phere of Titan, Saturn’s largestmoon, to broaden our understand-ing of organic chemistry in ourSolar System, perhaps discoveringan organic sea or a record of thesatellite’s organic history.

A number of flight programs thatwill go into implementation after2003 will also contribute vitally tothe search for life and its origins.For example, it is ironic that theancient surface on Mars may con-tain the best record in the SolarSystem of the processes that haveled to life on Earth. The MarsExploration Program will expandour understanding of volatiles onthe planet, study its atmospherichistory, and determine the elemen-tal composition and global charac-teristics of Mars’ surface. Futuremissions will explore the ancient


Studies of hot springs on Earth will help guide the search for life on other plan-

etary bodies by showing life at its limits and fossilization processes.

terrain and return samples, unveil-ing the Mars of over three billionyears ago and, perhaps, also unveil-ing the precursors to life on ancientEarth. Part of the challenge will beto establish criteria to distinguishbetween materials of biological andnon-biological origin both duringsample selection and in subsequentdetailed analysis of these sampleson Earth. We will continue tosearch for and analyze Martianmeteorites present on Earth tounderstand Mars and the exchangeof materials between planets.

An understanding of Saturn’smoon Titan could provide animportant bridge between thestudy of life’s chemical buildingblocks and the study of moreevolved environments such asMars and Earth. Follow-on toHuygens, Titan Explorer couldinvestigate chemical conditionsthat might be similar to the earlyenvironment of Earth, andcould offer a key to an ultimateunderstanding of the origin oflife.

Images of Europa, an ice-cov-ered moon of Jupiter, suggestexistence of a sub-surface worldof liquid water. We will pursuethis suggestion of a second liq-uid water world in our SolarSystem with the Europa Orbiter,scheduled for launch in mid-decade. Actually, the presence ofsubsurface liquid water worlds

now seems plausible in a num-ber of satellites of the outerplanets. These findings and ourunderstanding of the earlyappearance and ubiquity of lifeon Earth reinforce the suspicionthat life could exist elsewhere inthe Solar System. By applying anunderstanding of the early evo-lution of life on Earth, as well asof its ability to thrive in extremeenvironments here, we cansearch for evidence of life else-where in our Solar System. AEuropa Lander could be animportant next step for thisobjective.


If a Europa Lander returns evidenceof a subsurface water ocean, wecould consider how to carry outmore technologically difficult pene-tration of the frozen crust to huntfor life below by a Europa sub-surface explorer. As we learnmore about the potential for lifein the universe, astrobiologyresearch will suggest new targetsfor missions. For instance, alreadybeing contemplated as otherpotential water habitats areCallisto and the deep subsurface


Images of Europa’s surface indicate that water or slush may have oozed up

through cracks in its icy crust. This suggests that a subsurface ocean has

existed on this moon of Jupiter, and the discovery of a magnetic field around

Europa indicates that a liquid ocean is still there beneath the ice.

of Mars, which could also be tar-gets of very advanced spacecraft.

OBJECTIVE SEVEN:Understand our changing Sun and its effects throughout the Solar System

The Sun has profound effectsthroughout the Solar System, bothon the bodies that orbit our ownstar and on the space between them.To explain these effects, we need tounderstand both the inherent char-acteristics of the Sun and how itsemissions interact with the rest ofthe Solar System. These interactionsat Earth are particularly importantbecause of their practical near-term

effects (e.g., interference with satel-lite communications) and possiblelong-term implications (e.g., theeffects of solar variability on cli-mate). An understanding of the Sunand the consequences of its varia-tion are also needed if we are tocomprehend conditions at thedawn of life on Earth and predictour long-term future.

We are dramatically advancing ourknowledge of how the Sun worksthrough studies of solar interiordynamics. Using a growing fleet ofspacecraft, we are making coordi-nated measurements of events thatstart at the Sun, propagate throughinterplanetary space, and ultimate-ly impact Earth’s magnetosphereand upper atmosphere. The nextstep is a first survey of the region

where the terrestrial atmospheretransitions to space, opening a newview of the response of Earth’smagnetosphere to the solar wind.We are also gaining importantinsights into the workings of extra-terrestrial magnetospheres, explor-ing the most distant reaches of theSolar System, and completing thefirst exploration of the solar windat the Sun’s poles.

The Solar Terrestrial Probe (STP)program is a line of missions specif-ically designed to systematicallystudy the Sun-Earth system. TheSTP program seeks an understand-ing of solar variability on time scalesfrom a fraction of a second to manycenturies. It will also determinecause (solar variability) and effect(planetary and heliosphericresponse) relations over vast spatialscales. Our first STP projects are the Thermosphere-Ionosphere-Mesosphere Energetics andDynamics (TIMED) mission,NASA’s contribution to theJapanese Solar-B mission, andthe Solar Terrestrial RelationsObservatory (STEREO); thesewill proceed into implementationbefore 2003. Planned follow-onSTP missions focus on theresponses of near-Earth space tosolar input. MagnetosphericMultiscale (MMS) should helpus quantitatively understand thefundamental plasma physicsunderlying the processes (includ-ing magnetic reconnection, plas-


Solar activity interacts with Earth and its magnetosphere in complex ways.

ma turbulence, and energetic parti-cle acceleration) that control magne-tospheric dynamics and thus clarifythe impact of solar processes on thegeospace system. The GeospaceElectrodynamic Connections(GEC) mission will determine thespatial and temporal scales that gov-ern the coupling between the mag-netosphere and ionosphere, a majorstep toward understanding the con-nection between the solar wind,magnetosphere, and ionosphere.Magnetotail Constellation(MagCon) will employ a largenumber of very small satellites tomap the structure of the magnetos-phere. The availability of simultane-ous multi-point measurements frommissions such as MagCon will makeit possible to construct the firsthigh-fidelity “images” of the region-al structure of the magnetosphereand to characterize in detail itsresponse to variations in solar input.

Solar Probe will be our first voy-age to a star, a mission to explore

the near-environment of our Sun.Solar Probe will make a close flybyof the Sun, making the first in situmeasurements deep within itsouter atmosphere. In addition toproviding data essential for under-standing the source of the solarwind, these observations willallow us to relate remote observa-tions of solar phenomena to theactual physical processes thatoccur in the solar atmosphere.

The Gamma Ray Large ApertureSpace Telescope’s (GLAST) greatlyenhanced sensitivity relative to pre-vious high energy gamma ray instru-ments will allow detailed studies ofthe physical mechanisms underlyingthe vast energy releases observed insolar flares.

Living with a Star (LWS),described under Objective Eight,is a special NASA initiative thatdirectly addresses those aspects ofthe Sun-Earth system that affectlife and society. Its program ele-

ments include a space weatherresearch network; a theory, model-ing, and data analysis program;and space environment test beds.The first LWS mission will be theSolar Dynamics Observer, whichwill focus on the solar interiorwith the goal of understanding thesub-surface roots of solar activity.

Community-formulated missionsin the Explorer Program will takeadvantage of new scientific ideasand technologies to advance ourknowledge of the Sun-Earth con-nection. In addition, missionsundertaken within the DiscoveryProgram will also contribute to ourunderstanding of the terrestrial sys-tem. One example is informationon Mercury’s magnetosphere to bereturned by the MESSENGERDiscovery mission.


Atmospheric waves link the tro-posphere and upper atmosphereand redistribute energy withinthe ionosphere-thermosphere-mesosphere (ITM) system. Clustersof satellites using high-resolutionvisible and infrared sensors couldprovide ITM wave imaging,enabling us to understand genera-tion and loss mechanisms of thesewaves, their interactions, and theirrole in energy transport within theregion. Significant improvement


Passing within three solar radii of the Sun, inside its outer atmosphere, Solar Probe

will endure extreme conditions to provide unique data.

in infrared sensors will be requiredin order to enable this mission.

Understanding the heating andcooling of the solar corona by distin-guishing between proposed heatingmechanisms remains a challenge.Because much of the physics gov-erning this activity occurs very rap-idly and at very small spatial scales,this will require imaging andspectroscopic data able to resolvemicroscale coronal features.Implementation of such a missionwill require significant develop-ments in optics and detectors.

To fully understand the structureof the solar corona and to obtaina three-dimensional view of coro-nal mass ejections, we will needobservations from above theSun’s poles to complement dataobtained from the ecliptic plane.Viewing the Sun and innerheliosphere from a high-latitudeperspective could be achieved bya solar polar imager in a Sun-centered orbit about one half thesize of Earth’s orbit, perpendicu-lar to the ecliptic. Solar sail tech-nology will be required to put aspacecraft in such an orbit in areasonable time.

Future LWS missions will contin-ue to contribute importantly toour scientific understanding ofthe underlying physical processesthrough which the Sun impactsEarth and society.

An interstellar probe, travelingmore than 30 billion kilometers in15 years or so, could directlystudy for the first time how a star,our Sun, interacts with the sur-rounding interstellar medium. Onthe way, it would investigate SolarSystem matter beyond Neptune,and then determine the structureand dynamics of the shock wavethat separates our heliospherefrom the space between the stars.Continuing on, it would explorethe plasma, neutral atoms, dust,magnetic fields, and cosmic raysof the interstellar medium.

OBJECTIVE EIGHT:Chart our destiny in theSolar System

Evolutionary processes that haveshaped Earth and other planets are

still at work in the Solar Systemtoday. For example, there is strongevidence that large impacts causedbiological mass extinctions on Earthin the past, altering the course ofbiological evolution. The impact ofComet Shoemaker-Levy 9 onJupiter in 1994 vividly demonstrat-ed that major impacts still occurand could alter the future humanhabitability of Earth. The SpaceScience Enterprise supports thesearch for near Earth objects(NEOs). We believe there arebetween 700 and 1100 NEOslarger than 1 km whose orbitstraverse Earth’s, and we have dis-covered less than 450 of them todate. The motions of theseobjects are clearly of interest aspotential hazards. Many of themare also the easiest objects for aspacecraft rendezvous, and maycontain water or even rich min-eral deposits.


Hubble Space Telescope image of Jupiter in July 1994. The dark spots are

scars left by multiple impacts of the fragments of Comet Shoemaker-Levy 9.

Jupiter’s diameter is approximately eleven times that of Earth, which would fit

into the Great Red Spot (at left in the image).

We know that solar activity canstrongly affect daily life in today’stechnological civilization by caus-ing power-grid failures, temporarycommunications interruptions,and even outright failure of com-munications and defense satellites.Particle radiation from the activeSun can endanger astronauts inspace. Solar variability is also one ofthe natural drivers of global climatethat must be better understood foraccurate evaluation of the impact ofhuman activities on global climate.An understanding of the evolutionof the Sun and the consequences ofits variations are critical if we are toproperly understand the conditionsat the dawn of life and to predictour long-term future.

Future Solar Terrestrial Probemissions and Sun-Earth connec-

tion-related Explorers will contin-ue to improve our understanding ofsolar variability and how a habit-able environment is maintained onEarth in spite of it.

Living with a Star (LWS) is aNASA initiative that directlyaddresses those aspects of the Sun-Earth system that affect life andsociety. It includes a space weatherresearch network; theory, model-ing, and data analysis programs;and space environment test beds.The flight component of LWS is anetwork of spacecraft that will pro-vide coordinated measurementsfrom a variety of vantage points dis-tributed around the Sun and Earth.Analyzed together, these measure-ments will allow us to better under-stand and predict the effects ofspace weather events. The first

planned LWS mission is the SolarDynamics Observatory (SDO),which will observe the Sun’s outerlayers to determine its interiordynamics and the activity of thesolar corona, the source of sunspotsand active regions, and origin ofcoronal mass ejections. A secondLWS component is a constellationof Sentinels around the Sun toobserve the movement and evolu-tion of eruptions and flares fromthe dynamic Sun through the inter-planetary medium to Earth’s orbit.LWS geospace missions are theRadiation Belt Mappers and theIonospheric Mappers. TheRadiation Belt Mappers will char-acterize the origin and dynamics ofterrestrial radiation belts and deter-mine the evolution of penetratingradiation during magnetic storms.The LWS Ionospheric Mapperswill gather knowledge of howEarth’s ionosphere behaves as a sys-tem, linking incident solar energywith the top of Earth’s atmosphere.

Beyond elucidating events andprocesses that might affect our des-tiny on Earth, missions to theMoon, Mars, and near-Earth aster-oids will also contribute to ourunderstanding of potential humandestinations in the Solar System.Lunar Prospector returned evi-dence for hydrogen, possibly in theform of water ice, trapped in per-manently shadowed regions nearour Moon’s north and south poles.Goals of the Mars Exploration


Living With a Star is a new initiative to understand space weather and the

effects of the Sun on Earth. Various LWS spacecraft will provide information

about Earth’s upper atmosphere, the heliosphere, and the Sun itself.

Program include investigatingselected sites on that planet in detailand improving our understandingof how to ensure the safety andeffectiveness of future humanexplorers, and perhaps eventuallysettlers. Future missions to Earth-approaching asteroids will assessthe resource potential of theseobjects.


Future elements of the LWSInitiative will provide coordinatedmeasurements from an improvedspace weather research network,distributed around the Sun andEarth, to advance our ability tounderstand and predict spaceweather events and their effects.Future LWS components, such as asolar-polar orbiter and Earthnorth and south “pole-sitters,”are under study.

The Mars Exploration Programwill continue and will build on the results of the nearer-term mis-sions. From laboratory studies andspace experimentation, astrobiologyresearch may reveal whether life islimited to its planet of origin or canexpand its evolutionary trajectorybeyond. Outer Solar System mis-sions to Europa and Titan wouldhelp clarify the larger context for lifein our own family of planets andsatellites.


Living With a Star

The Living With a Star Initiative is a set of missions and enhance-ments to our current program to augment our study of solar vari-ability and its effects. Why do we care? The sphere of the humanenvironment continues to expand above and beyond our planet.We have an increased dependence on space-based systems, apermanent presence of humans in Earth orbit, and eventuallyhumans will voyage beyond Earth. Solar variability can affectspace systems, human space flight, electric power grids, GPSsignals, high frequency radio communications, long range radar,microelectronics and humans in high altitude aircraft, and Earth’sclimate. Prudence demands that we fully understand the spaceenvironment affecting these systems. In addition, given the enor-mous economic impact of even small changes in climate, weshould fully understand both natural and anthropogenic causes ofglobal climate change.

The Living With a Star Initiative includes:

• A space weather research network of spacecraft providingcontinuous observations of the Sun-Earth system for inter-locking, dual use, scientific and applications research.

• A special data analysis and modeling program targeted at (1)improving knowledge of space environmental conditions andvariations over the solar cycle, (2) developing techniques andmodels for predicting solar and geospace disturbances thataffect human technology, and (3) assimilating data from net-works of spacecraft.

• Space Environment Test beds for low cost validation of radi-ation-hardened and radiation-tolerant systems in high radia-tion orbits.

• Establishing and expanding partnerships for interdisciplinaryscience and applications with other NASA programs (EarthScience, Human Space Flight, Life Sciences), with otherFederal agencies (e.g., via the interagency National SpaceWeather Program), with international collaborators, andwith industry.


The next generation of spacecraft that will carry out our broad program of

exploration must be more capable and more reliable while being more efficient

in mass and power consumption. Some systems (telescopes, for example) will

be much larger than today’s; others (in situ probes for space physics, for exam-

ple) will be much smaller. During the preparation of this Strategic Plan, the

roadmap teams in the major Enterprise science areas that formulated science

goals and collected and assessed mission concepts also analyzed the techni-

cal capabilities that would be needed to implement these concepts. These

Enterprise technology needs were aggregated into ten key capability areas.

76

t echno logy p rog ramSection II-4Section II-4

Key Capabilities

Advanced power and on-boardpropulsion are needed to supportmore capable instrumentation andtelemetry, as well as to enable space-craft to travel deeper and fasterinto space. Development in theseareas will focus on power genera-tion (solar and nuclear) and ener-gy storage (battery technologiesand flywheels); chemical, ionpropulsion, and attitude controlsystems; solar sails; and micro-propulsion systems and compo-nents.

Sensor and instrument compo-nent technology progress is need-ed to provide new observationalcapabilities for astrophysics,space physics, and planetary sci-ence remote sensing, as well asvehicle health awareness. Areasfor future work include miniatur-ized in situ and advanced remotesensing instruments, and newsensing techniques using distrib-uted spacecraft and bio-sensorsfor astrobiology. Of particularimportance to space science is

instrument capability to performin harsh environments: vacuum,extreme temperatures, and intenseradiation fields. New detectortechnologies will be based onfundamentally new measure-ment principles and techniques

using new materials and architec-tures, as well as expanded use ofdifferent spectral regions.

Many future mission conceptsrequire constellations of platformsthat act as a single mission space-craft for coordinated observationsor in situ measurements, or actas a single virtual instrument(for example, interferometry ordistributed optical systems).Major areas for work in distrib-uted spacecraft control are:advanced autonomous guidance,navigation, and control architec-tures; formation initializationand maintenance; fault detec-tion and recovery; and inter-satellite communications.

High rate data delivery isessential to support virtual pres-ence throughout the SolarSystem. We also want to mini-mize the mass and resourcerequirements of communicationssubsystems. Topics for advanceddevelopment in high rate datadelivery include: informationextraction and compression; low-

technology program | 77

Of particular

importance to

space science

is instrument capa-

bility to

perform in harsh

environments:

vacuum, extreme

temperatures,

and intense

radiation fields.

cost, low-mass systems; opticalcommunications; in situ com-munications for surface explo-ration; improved componentsfor deep space communications;and high rate distributed infor-mation systems.

Very advanced space systems willbe self-reliant, self-commanding,and even inquisitive. Theseintelligent space systems mustbe able to: plan and conductmeasurements based on currentor historical observations orinputs; recognize phenomena ofinterest and concentrate activi-ties accordingly; and monitorand maintain desired status orconfiguration over long periodsof time without frequent com-munication with ground.

Many science objectives benefitfrom more populous spacecraftconstellations or more frequentflight opportunities at a fixed cost.The former category includesconstellations of measurementplatforms in flight as well as net-works of landed spacecraft for insitu measurements. These micro-or nano-sciencecraft would have:smaller, more lightweight, morecapable and resource-efficientspacecraft “bus” and “payload”components; efficiently integratedbus-payload spacecraft designs;high performance data compres-sion technology; low power, highperformance electronics; and

micro-electromechanical systems(MEMS) technology.

Advances in exploration of plan-etary surfaces will depend onsurface systems technologies forsafe, self-sufficient, and self-sus-taining robotic and human pres-ence independent from Earth forindefinite periods of time. Basictechnology elements needed forsurface and sub-surface samplingof planetary surfaces and smallbodies will be teleoperated, alongwith autonomous robots androvers with increased intelli-gence, speed, maneuverability,and dexterity. Specific capabili-ties would include drills, coringdevices, and scoops, as well assample handling, packaging, andreturn mechanisms.

Very large (km-scale) non-preci-sion structures in space (e.g.,sunshields, sails) and large(100m) precision structures (e.g.,optical reflectors, antennas) levy

new requirements for ultra-lightweight space structuresand observatories. Progress isneeded in: materials; inflatableand deployable structures,including control for precisiondeployment and maintenance;lightweight optics and opticalstructures, and thin-film materi-als; and radiation shielding, sur-vivable spacecraft materials, andtelescope technology.

Improved reliability and agilityare needed for in-space dockingand flight in planetary atmos-pheres. Atmospheric systemsand in-space operations devel-opment will focus on aero-maneuvering (ascent, entry, anddescent systems, and aero-shelland hazard avoidance systems),aerial systems (balloons, air-planes, rotorcrafts, and gliders),and operations (rendezvous,docking, and sample transfersystems).

To bring all of these advancedflight capabilities together in inno-vative mission designs, we willneed a next generation infra-structure on the ground. This willinclude high performance com-puting and networking, supportfor collaborative work, advanceddesign tools, and distributed net-works of computer resources.Tools will be developed to increaseefficiency and speed of technologymaturation and infusion.


Very advanced

space systems

will be self-reliant,

self-commanding,

and even inquisitive.

1. The Boomerang micromesh bolometer, reminiscent of a spider’s web, uses a free-standing micromachined mesh of

silicon nitride to absorb millimeter-wave radiation from the cosmic microwave background. Millimeter-wave radiation is

absorbed and measured as a minute temperature rise in the mesh by a tiny Germanium thermistor, cooled to three tenths

of a degree above absolute zero. 2. Aerogel, a low density material made from silicon dioxide, is protecting some crayons

from the heat of the flame. Aerogels have primarily been used in scientific applications, most commonly as a particle

detector in high energy physics. 3. An ultrasonic driller/corer developed at NASA Jet Propulsion Laboratory is shown

drilling sandstone while being held from its power cord. Relatively small vertical force is used in this application—a fac-

tor that will be useful when the drill is used in future space missions to drill and core for samples during planetary and

asteroid explorations. 4. A high power plasma thruster operates at a current level of 20,000 amperes and a peak power

level of 10 megawatts. The technology may eventually be used to propel cargo or piloted vehicles to Mars and beyond.

5. This new microgyroscope is lighter, cheaper, higher-performing, and less complex than its conventional counterparts

while uniquely designed for continuous space operation. Its dimensions are 4 by 4 millimeters, smaller than a dime, and

its weight is less than one gram. 6. The Goldstone Deep Space Communications Complex, located in the Mojave Desert

in California, provides radio communications for all of NASA’s interplanetary spacecraft and is also utilized for radio

astronomy and radar observations of the Solar System and the universe.


1 2

3 4

65


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The TechnologyLife Cycle

Taken with the Agency’s Cross-Enterprise Technology Programthat focuses on early stage tech-nology research, Enterprise tech-nology programs span the fullspectrum of technology maturi-ty, from fundamental seed ideasthrough flight validation. Theconcept of Technology ReadinessLevels (TRLs) provides a system-atic approach to technologymanagement that supportsmaturity assessment and a con-sistent comparison of maturity

between different types of tech-nology. Technology productstypically progress through thedevelopment cycle through mul-tiple programs. For instance,after an advanced proof-of-con-cept is demonstrated, it may betransitioned into either theEnterprise focused program orinto the cross-Enterprise pro-gram for continued develop-ment, depending on the breadthof its applicability. This wouldbe followed by system-leveldevelopment and flight valida-tion in the focused or flight vali-dation programs.

Enterprise Technology Program Components

The Space Science Enterprise tech-nology program to advance thestate-of-the-art in the ten focusareas is organized into three majorelements: an advanced conceptsprogram, a focused technology pro-gram, and the New Millenniumflight validation program.

The Advanced Concepts Programconducts studies for far-termtechnology (10-25 years in thefuture) by eliciting long-range sci-ence ideas, developing relevantfar-term system concepts, andthen deriving technology require-ments and innovative approachesto support them.

The Focused Technology Programaddresses high-priority technologyrequirements that directly supportmissions in the Enterprise StrategicPlan. While activities within thisprogram are driven by the needs ofspace science, other Enterprisesoften benefit from them.

The New Millennium Programcompletes the technology devel-opment life cycle by validatingnew technologies in space. Inaddition to dedicated technolo-gy missions, other flight valida-tion platforms, including theSpace Shuttle and InternationalSpace Station, balloons, sound-ing rockets, and piggyback space-


A broad range of new technologies will be needed to carry out future space sci-

ence missions. For planetary exploration, these include communications,

instrumentation, descent systems, and intelligent mobile platforms.


craft or launch vehicle opportu-nities are also used to validatetechnologies in the space envi-ronment. Demonstrations flownas secondary payloads on expend-able launch vehicles flown byNASA, or co-manifested onother U.S. Government or com-mercial concerns’ launches, offerstill other opportunities. Thepossibility of cooperation withininternational partnerships fortechnology demonstration is alsobeing explored.

In addition to these major Enter-prise technology programs, theEnterprise provides requirementsto, and benefits from, Agencywidetechnology programs: Cross-Enterprise Technology DevelopmentProgram (CETDP), High Perfor-mance Computing Capability(HPCC), and NASA Institute forAdvanced Concepts (NIAC). Theseprograms support technologyrequirements for all NASA spaceEnterprises, focusing on early stagesof the technology life cycle for mul-tiple Enterprise users. They empha-size basic research into physicalprinciples, formulation of applica-tions concepts, and component-level performance evaluation.

The program analyses performedin conjunction with the prepara-tion of this Plan have revealedgaps in the capability to meet thetechnology needs of the SpaceScience Enterprise and its future

expansion. We are therefore tak-ing steps to fill these gaps by pro-posing a new technologyinitiative that encompasses sev-eral programs. These includeSystems at the Edge (focusing onlow TRL research), Accessing thePlanets (for in situ planetaryexploration), Flight ValidationTransition (promoting transitionof new technologies to spacedemonstration), and a LargeSpace Telescope Initiative (forfar-term space observatories).

Technology Management

Management of the technologylife cycle for strategic, NASA-for-mulated missions begins with thescience theme roadmaps describedin Section II-1. The Enterpriseallocates resources in the FocusedTechnology Program and estab-lishes priorities for the NewMillennium Program and theCross-Enterprise Program. TheResearch and Analysis program’syearly research solicitation alsoreflects the priorities establishedby the Science Board of Directors.

The technology programs arereviewed quarterly by Enterprisemanagement. A TechnologySteering Group, staffed by keyprogram technologists at theNASA Centers, analyzes on acontinuing basis the efficiencyof resource allocations (gaps,overlaps, and redundancies) inthe technology programs. TheSteering Group reports periodical-ly to Enterprise management. TheSteering Group uses a variety ofsystem analysis, risk analysis, andinvestment analysis tools andprocesses to determine the relativebenefits and costs of alternativetechnologies, both those developedinternally and those provided byuniversity and industry partners.

Selected technology programs areperiodically peer reviewed by

In addition to

these major

Enterprise

technology

programs,

the Enterprise

provides

requirements to,

and benefits from,

Agencywide

technology

programs.

external expert technologists onbehalf of Center and Headquartersmanagement. On the basis of thesereviews and reports, reallocation ofresources is considered by theEnterprise every year during thebudget development process orwhenever appropriate in responseto deviations from planned per-formance or budgets.

Technology infusion into the community-formulated Explorerand Discovery programs occursby a different path, since thesemissions are proposed as inte-grated packages by the research

community and proceed directlyto detailed definition withoutthe benefit of a lead-in technol-ogy development program. Forthe Explorer program, an annualresearch solicitation offers atechnology funding opportuni-ty, primarily for instrumentdevelopment. The Research andAnalysis program offers a com-petitive program for funding ofinstrument development forplanetary exploration. The select-ing official has the option to allo-cate a small amount of fundingfor a proposal of unusual scientif-ic merit that is not selectable

because it is considered technical-ly immature. Up-to-date informa-tion on technologies consideredready to fly is provided to pro-posers in the Explorer andDiscovery programs, as well as tothe proposal reviewers to ensurethat a consistent standard fortechnical readiness is applied dur-ing the review process. Finally,technology developments sup-ported under the FocusedTechnology Program for theNASA-formulated missions alsobecome available to communityproposers in the Explorer andDiscovery programs.



Underpinning the space science flight programs are two programs of space

science activities called Research and Analysis (R&A) and Data Analysis (DA)—

collectively called Research and Data Analysis (R&DA). Broadly put, research

supported under R&DA programs develops the theoretical tools and laborato-

ry data needed to analyze flight data, makes possible new and better instru-

ments to fly on future missions, and analyzes the data returned so that we can

answer specific questions posed and fit them into the overall picture. Although

priorities within both programs are established in accordance with the

Enterprise strategic goals, the program types differ in scope. While DA pro-

grams are tied to specific missions, which are focused on the achievement of

specific strategic objectives, the scope of R&A programs is generally wider

86

resea rch and da ta ana l ysSection II-5Section II-5

because they must provide thenew theories and instrumentationthat enable the next generation offlight missions.

The alignment of R&A programswith Enterprise strategic goals isensured through two mecha-nisms. First, NASA ResearchAnnouncements soliciting R&Aproposals contain explicit prior-itization criteria with respect toEnterprise objectives. Second,the entire R&A program isreviewed triennially to assess sci-

entific quality and productivity ofthe major components and toadjust plans to best supportEnterprise goals.

Data Analysis (DA) programshave traditionally been per-formed by mission instrumentteams and interdisciplinary sci-entists competitively selected foran individual mission for thelifetime of that mission. Forsome missions or missiongroups, periodic open and com-petitive solicitations enable DA

participation by other investiga-tors. As a matter of principle,the Enterprise has begun to addannual, open and competitiveDA solicitations to all missionsthat can accommodate “guestinvestigations.”

Without a vigorous R&DA pro-gram it would not be possible toconduct a scientifically meaning-ful flight program. Examples ofthe contributions of the R&DAprogram abound across the wholefrontier of space science.

research and data analysis | 87

ys i s

Role of NASA’s Research and Data Analysis Programs

In a recent study (Supporting Research and Data Analysis in NASA’s Science Programs: Engines forInnovation and Synthesis, National Research Council, 1998), the Space Studies Board identified R&DAfunctions that are “integral elements of an effective research program strategy”:

• Theoretical investigations• New instrument development• Exploratory or supporting ground-based and suborbital research• Interpretation of data from individual or multiple space missions• Management of data• Support of U.S. investigators who participate in international missions• Education, outreach, and public information

Objectives of R&DA Programs

Theoretical, modeling, andlaboratory work provide thetools to understand and inte-grate measurements made inspace and on the ground, andcan also directly impact futuremission concepts. Numericalmodeling of impacts and mag-netohydrodynamics supportboth planning for future mis-sions and understanding of datareturned from past ones.Laboratory experiments, inturn, are used to validate thesetheoretical results. The R&A-supported laboratory work onmeteorites underpins researchon asteroids, as well as continu-ing analysis of fragments thatare believed to have come toEarth from Mars. In a differentvein, models for the atmosphereof Mars can be used to predictthe performance of aerobrakingsystems for future spacecraft.The R&A Planetary ProtectionProgram is developing methodsto completely sterilize ice-pene-trating probes so that we can oneday confidently search for life onEuropa without fear of a spuri-ous detection due to contamina-tion from Earth. And samplereturns from Mars cannot beundertaken until the possibilityof contamination of our ownplanet is fully understood andeliminated.

Exciting new revelations about thecosmos are not possible withoutthe most advanced detector andinstrument systems that can bebuilt, most of which are developedthrough competitively-selectedspace science R&A programs.Many are given real-life testing inthe sounding rocket and balloonprograms before the decision ismade to fly them on the muchmore expensive Earth-orbiting anddeep space spacecraft. The new-generation detectors for theHubble Space Telescope, theChandra X-ray Observatory, Solarand Heliospheric Observatory, and

the upcoming Space InfraredTelescope Facility were largelydeveloped within the R&A pro-gram. Similarly, future generationsof instruments slated for possibleuse on our planetary missions arebeing designed and built withinthe R&A program. As illustratedin the table “Examples of FlightHardware with R&A Heritage”(p.89), instrument conceptsdeveloped through the R&A pro-gram have been the basis forflight instrumentation for everyclass of NASA flight mission,from the smallest to the GreatObservatories.


Time exposure of a hypervelocity oblique impact, from the right of the frame.

Low-angle impacts cause the projectile to fragment, and significant pieces sur-

vive to disperse downrange without much change in velocity. (NASA Ames

Vertical Gun Range)

After we have obtained them, wemust analyze and interpret datareturned by NASA’s space sciencemissions to fully exploit them foraddressing our strategic scienceobjectives. R&A and DA supportthe necessary advanced modelingand theory. For example, recentcomputational modeling of the

convective upwelling in Europa’sice shell has been used to interpretthe “blisters” observed by theGalileo spacecraft to estimate thethickness of the shell and thedepth of a possible liquid waterocean beneath it. Other Galileodata have been analyzed to revealthe physical state and major

dynamical processes withinJupiter’s turbulent atmosphereand on the surfaces of the giantplanet’s diverse satellites. Ourunderstanding of the effects onEarth of the nearest star, theSun, is progressing as a result of interpretation of data fromsuch missions as the Solar and


Examples of Flight Hardware with R&A Heritage

Chandra Focal plane detectors

Cluster Electron and ion analyzer predecessors

EUVE Wedge and strip detectors

Mirror

FAST Wave-particle correlator

Multiple-baseline electric field interferometer

FUSE Holographic grating

Delay-line detectors

Mirror

Galileo Ebert-Fastie spectrometer

Hubble Space Telescope Multi-anode microchannel plate array detector

Lunar Prospector Electron reflectometer

SNOE X-ray photometer

SOHO Ultraviolet spectrometer

Delay-line detectors

Multi-layer imaging

TIMED Ultraviolet imager

TRACE Normal incidence multilayer filters

Wind Wave-particle correlator

Electron and ion analyzer predecessors

Yohkoh Glazing incidence x-ray optics

Heliospheric Observatory (SOHO)and the Transition Region andCoronal Explorer (TRACE). Avery practical example is coronalmass ejections, which directlyaffect—in some cases perma-nently damage—Earth-orbitingcommunications satellites. Acomplete understanding of theseejections could have very signifi-cant benefits to our nationalsecurity and to the space com-munications industry. In themore remote universe, R&DAsupports investigations into one

of the long-standing enigmas inastrophysics, the nature ofgamma ray bursts. During briefflashes, these objects scatteredover the sky are individually thebrightest objects in the universe.A major advance was recentlyachieved when the visible coun-terpart to one of these bursterswas observed simultaneouslywith its detection in gamma rays.Equally exciting, fine details ofthe fossil microwaves remainingfrom the Big Bang were revealedfor the first time by one of a

series of balloon-borne experi-ments from the Antarctic.

Vast amounts of data arereturned from space sciencemissions. The volume, richnessand complexity of the data, aswell as the need to integrate andcorrelate data from multiplemissions into a larger contextfor analysis and understanding,present growing opportunities.Exploration and discovery usingwidely distributed, multi-ter-abyte datasets will challenge all


Looking at the World in New Ways

R&A supported work that revealed the existence of a distinct and perhaps ancient type of microorgan-ism, first christened archaeabacteria. Further studies supported this initially controversial theory. Whenthe genomic sequence ofMethanococcus jannischiiwas published, our perceptionof the taxonomy of life onEarth was sweepingly revisedto today’s three domains: bac-teria, eukarya, and archaea.NASA-supported researchersthus discovered a previouslyunrecognized branch of life onEarth, an advance with pro-found implications for thesearch for life elsewhere in theuniverse.

aspects of data managementand rely heavily on the mostadvanced analysis and visualiza-tion tools. The design andimplementation of the next gen-eration of information systemswill depend on close collabora-tion between space science

and computer science and tech-nology.

An example of such a collaborationis a National Virtual Observatory(NVO) initiative to collect most ofthe Nation's astronomical data,along with advanced visualization

and statistical analysis tools. Thiswill support "observations" and dis-covery via remote access to digitalrepresentations of the sky in allwavelengths. The NVO will pro-vide multi-wavelength data for mil-lions of objects, allowing discoveryof significant patterns from the


Accelerating Scientific Progress

BOOMERANG was designed to image the Cosmic Microwave Background (CMB). Work onBOOMERANG began shortly after the first detection of anisotropy by the COBE spacecraft. ThoughCOBE detected anisotropy in the CMB, it was not able to resolve it. The challenge was to construct anexperiment that could image the CMB with 40 times the angular resolution and 100 times the instanta-neous sensitivity of COBE. This was achieved by the BOOMERANG instrument, which was launched ona 10-day Antarctic voyage in late 1998, carrying a detector that had not existed just four years before.The results offer the first strong confirmation of the idea that the universe underwent a period of violent“inflation” during the first nanosecond after the Big Bang.

The BOOMERANG Telescope being readied for launch near Mt. Erebus in Antarctica. The 28 million cubic foot bal-

lon carried the BOOMERANG telescope to an altitude of 120,000 feet, above 99 percent of the atmosphere.

exploration and mining of the sta-tistically rich and unbiased databas-es. Another example is the datamanagement and computing chal-lenge posed by the Living With aStar (LWS) initiative. Special chal-lenges posed by LWS include highperformance computational meth-ods for theoretical modeling andsimulation, complex data analysisand visualization tools, correlativedata analysis and visualization capa-bilities across widely varying spatialand temporal scales, and assimila-tion of observational data into theo-retical models.


Images of the supernova SN1987A; combining information from several wave-

lengths helps unravel the mechanisms of astronomical phenomena. Clockwise

from upper left: HST optical image; Australian Telescope Compact Array radio

image; Chandra x-ray images from January 2000 and October 1999.


Setting the Stage for Future Missions

The Galileo mission has provided evidence that Europa has a liquid water ocean beneath its frozencrust, leading to speculation about possible sources of energy to support life in this ocean. Studieshave indicated that without a ready supply of oxidized chemical species, the energy available for lifewould be minimal and any life on Europa would be very limited and difficult to detect. However, arecently developed alternative theory has revealed a novel pathway for chemical energy to be deliveredto Europa. In this scenario, the intense radiation field surrounding Jupiter would produce oxidized andreduced carbon species that would be available to support life. This result is a vital consideration forthe design of missions to search for life on Europa because it suggests searching the near-surfacerather than penetrating kilometers of ice.

Responding to Unexpected Opportunities

On February 23, 1987, astronomers detected the first nearbysupernova in 400 years. For the gamma ray measurementscritical to understanding how new elements are formed insuch a massive stellar explosion, NASA turned to its subor-bital program as the only possible way to take advantage ofthis unprecedented but short-lived opportunity. A campaign ofscientific balloon flights using gamma ray telescopes devel-oped under the R&A program provided crucial evidence ofhow supernovae produce the heavy elements we see onEarth. Combined with observations from the ground and fromspace at other wavelengths, these gamma ray observationswere key to developing a comprehensive picture of this stellarexplosion.

Enabling a New Science

One of our most compelling questions is whether or not we are alone in the universe. If we are not,how does life emerge and evolve elsewhere in the universe? In fact, how did it appear on Earth? Whatis the future of life on Earth? These questions are the focus of the astrobiology and exobiology R&Aprogram. Astrobiology has been at the forefront of an effort to break down discipline barriers to pro-mote vigorous research at the boundaries between traditional scientific disciplines. Scientific debateon the potential for life on Europa, and even speculation on its possible nature, are recent examples ofthe resulting cross-disciplinary research that could motivate future missions.

To stimulate progress in astrobiology, the Space Science Enterprise recently created the AstrobiologyInstitute. The new Institute is an innovative virtual organization in which scientists throughout the coun-try coordinate their research—and soon will be carrying out experiments—via high-speed computerlinks. It may be the most practical and efficient way to harness the highly diverse expertise of a geo-graphically dispersed investigator population. The Astrobiology Institute will pioneer the technologythat will enable teams of researchers and equipment scattered around the country, or even the world,to carry out front-line investigations.

Supernova SN1987A


Space Science Enterprise education and public outreach goals center on sharing

the results of our missions and research programs with wide audiences and using

space science discoveries as vehicles to improve teaching and learning at all lev-

els. This is a deliberate expansion of the traditional role of the Enterprise in sup-

porting graduate and postgraduate professional education, a central element of

meeting our responsibility to help create the scientific workforce of the future.

Our commitment to education now includes a special emphasis on pre-college

education and on increasing the general public’s understanding and appreciation

of science, mathematics, and technology.

94

educa t i on and pub l i c ou tSection II-6Section II-6

Our policy for achieving oureducation and public outreachgoals and objectives is to incor-porate education and publicoutreach as an integral compo-nent of all of our activities, bothflight missions and researchprograms. Contributing to edu-cation and outreach is the collec-tive responsibility of all levels ofEnterprise management and of allparticipants in the space scienceprogram. We focus on identifying

and meeting the needs of educa-tors and on emphasizing theunique contribution space sciencecan make to education and thepublic understanding of science.Our approach facilitates the effec-tive participation of space scien-tists in education and outreachactivities. Enterprise efforts are asignificant element of NASA’soverall education program and arealigned with the Agency’s effortsto ensure that participation in

NASA missions and research pro-grams is as broad as possible.

The two main elements of our edu-cation and public outreach programare support to education in theNation’s schools and informal edu-cation and public outreach thatbenefits both young people andadults.

With limited resources, high lever-age is key to building a national pro-

education and public outreach | 95

u t reach

Education and Outreach Implementation Approach

• Integrate education and outreach into Enterprise flight and research programs• Encourage a wide variety of education and outreach activities• Help space scientists participate in education and public outreach• Optimize the use of limited resources by channeling individual efforts into highly leveraged

opportunities• Develop high quality education and outreach activities and materials having local, state, regional,

and national impact• Ensure that the results of our education programs and products are catalogued, archived, and

widely disseminated • Evaluate our activities for quality, effectiveness, and impact

gram that contributes both toimproving teaching and learning atthe pre-college level and to increas-ing the scientific literacy of the general public. The Enterpriseachieves this leverage in pre-collegeeducation by building on existingprograms, institutions, and infra-structure and by coordinating activ-ities and encouraging partnershipswith other ongoing educationefforts. Such ongoing effortsinclude those inside NASA andwithin other Government agencies,and those being undertaken by non-governmental educationorganizations. We complement thevery large investments in educationbeing made by school districts, indi-vidual States, and other Federal

agencies, particularly by the NationalScience Foundation and theDepartment of Education. Thisentails establishing alliances witheducation-oriented professional soci-eties, state departments of education,urban school systems, educationdepartments at colleges and univer-sities, and organizations that pro-duce science materials intended fornational distribution. Our effortssupport local, state, and nationalefforts toward standards-based sys-temic reform of science, mathemat-ics, and technology education. Weuse existing dissemination net-works and modern informationtechnology to make informationand education programs and mate-rials easily accessible.

The other main element of our pro-gram, enhancing the general pub-lic’s understanding of science,develops new connections withinformal education and publicoutreach organizations of manydifferent types across the country.Alliances have been established withscience museums and planetariums,as well as producers of public radioand television programs.

We will continue to explore newpossibilities for partnerships and toexperiment with new ways tobring the results of the space scienceprogram to teachers, students, andthe public. For example, we willexpand current partnerships andcreate new alliances with organiza-tions such as the Boys and GirlsClubs of America, Girl Scouts ofAmerica, 4-H Clubs, professionalsocieties for scientists and educators,public libraries, and rural museums.

We have made significant progressin these areas since the previousEnterprise Strategic Plan wasreleased in 1997. We have embed-ded funded education and publicoutreach programs in all of ourmission and research programs,established dozens of local, region-al, and national partnerships, andestablished a national support net-work of education and outreachforums and brokers-facilitators(fully described in a separateEnterprise education and publicoutreach implementation plan).


Space science brings together inquiring minds of all ages.

New education and public out-reach efforts will build on theseactivities and accomplishments. Forexample, we will:

• Emphasize collaborations withscience museums and planetar-iums. Collectively, these insti-tutions attract more than 100million visitors per year. Theyhave enormous experience indeveloping and presentingpublic education programs.They also have the resourcesfor creating such programs andare playing an increasinglyimportant role in workingwith the formal education sys-tem. We plan to build onstrong mutual interestsbetween the Space ScienceEnterprise and the museumand planetarium community.

• Take advantage of the hightechnology nature of much of

the Space Science Enterprise’sprogram to develop new mate-rials and new programs in tech-nology education. Many of thetechnologies being developedfor our science program are alsoof great interest to the public,and we will explore ways tobring our technology as well asour science to the public.

• Develop, in collaboration withthe NASA Office of EqualOpportunity Programs, newopportunities for underservedand underutilized groups toparticipate in space science mis-sions, research, and educationand outreach programs.

• Evaluate our education andoutreach products and pro-grams for quality and effective-ness. We must understand whoour programs are reaching andwhat impact they are having,both on the formal education

system and on the general pub-lic’s understanding of science.We will continue to improveour efforts based on regularfeedback.

• Be alert for special events andparticularly promising oppor-tunities in our scientific pro-gram to bring space science to the public and to use spacescience to improve science,mathematics, and technologyeducation at all levels. Forexample, our planned long-term program of Mars explo-ration provides an opportunityto literally “bring the Americanpublic along for the ride” andbecome genuine participantsin the adventure of exploringanother planet.

The full variety and scope of theEnterprise’s current and plannededucation and outreach activitiesare described in our 1996 report“Implementing the Office ofSpace Science Education/PublicOutreach Strategy.” Our systemicapproach, based on a long-termcommitment to partnership withexisting education and public out-reach institutions, is making a sig-nificant and durable contributionto education and public under-standing of science, mathematics,and technology.

education and public outreach | 97

The Space Weather Center exhibit introduces visitors to space weather and

how it affects everyday life. An interactive exhibit, it incorporates near real-time

data from NASA missions currently studying the Sun and near-Earth space.

(The exhibit is a partnership of the Space Science Institute and NASA Goddard

Space Flight Center.)


NASA’s space science program exists within a much larger research and

technology context that spans the globe. In some areas space science leads

the pace of innovation, and in others it benefits from efforts and investments

of others. Our pace of discovery is quickened by contributions from other

U.S. Government agencies, U.S. universities and industry, and scientific

collaborators around the world.

98

pa r tne r sh ipsSection II-7Section II-7

Other NASA Enterprises

Partnerships with other NASAEnterprises are essential to theSpace Science Enterprise strategy.For example, the Space ScienceEnterprise works with the HumanExploration and Development ofSpace (HEDS) Enterprise to pro-vide information essential tofuture human exploration anddevelopment of the Solar System.This includes scientific informa-tion about likely human destina-tions such as the Moon and Mars,surveys and characterization ofspace resources, and evaluation ofspace radiation hazards. The part-nership with HEDS also involvesusing Enterprise missions to testtechnologies for human explo-ration of space and planetaryenvironments.

HEDS, in turn, provides theSpace Science Enterprise oppor-tunities to accomplish investiga-tions that would otherwise beimpractical. For example, theSpace Shuttle flies science pay-

loads such as telescopes to studythe ultraviolet universe, sub-satel-lites to study the solar corona andthe origin of solar wind, and cos-mic dust collection experiments.The International Space Station

will provide further opportunitiesfor these and other types of inves-tigations. Ultimately, some of themost important and complex sci-ence goals, such as understandingthe possible origin and evolutionof life on Mars, will be addressedby human explorers. Indeed,

answering questions of this mag-nitude may prove to be a signifi-cant part of the rationale forhuman exploration. Moreover,ambitious future space observato-ries may depend on human assis-tance in assembly, maintenance,and upgrading; the history of theHubble Space Telescope providesbrilliant examples of this synergy.

The Space Science, Earth Science,and new Biological and PhysicalResearch Enterprises are jointlydeveloping a program in Astro-biology, a new multidisciplinaryresearch field that studies the ori-gin and distribution of life in theuniverse, the role of gravity in liv-ing systems, and Earth’s atmos-phere and ecosystems.

Our studies of the Sun, the near-Earth space environment, Earth’smiddle and upper atmosphere,and other planets are also of inter-est to the Earth science communi-ty. For example, variations in solarradiation and particle emissioncause variations in Earth’s atmos-

partnerships | 99

Partnerships with

other NASA

Enterprises are

essential to the

Space Science

Enterprise strategy.

phere. The study of other planets,particularly Venus and Mars, isanother avenue to understandingwhy Earth is capable of sustaininglife, and how global changeprocesses might operate in otherplanetary settings.

The Aerospace Technology Enter-prise also makes important contri-butions to the Space ScienceEnterprise. For example, aeronau-tics expertise at Ames ResearchCenter supports the SOFIA air-borne observatory program.

Our education and outreach pro-grams are carried out in close col-laboration with the Office ofHuman Resources and Educationand the Office of Equal Oppor-tunity Programs to ensure thatspace science initiatives comple-ment existing activities and sup-port NASA’s overall programs inthese areas.

Other U.S. Government Agencies

The National Science Foundation(NSF) has many programs thatsupport or enhance NASA spacescience missions. NSF-supportedground-based research on theSun, the planets, and the universecontribute to the intellectualfoundations of many NASA spacescience flight missions. NASA andNSF jointly fund planet search

programs. NSF is also responsiblefor U.S. scientific activities in theAntarctic. NSF, the SmithsonianInstitution, and NASA collabo-rate on the search for, collection,distribution, and curation ofAntarctic meteorites. NASA andNSF have a joint program to useAntarctica as an analog for thespace environment in developinglong-range plans for Solar Systemexploration. NASA also usesAntarctica for a future generationof very long-duration balloonmissions. There are close tiesbetween NASA’s astrobiology pro-grams and NSF’s Life in ExtremeEnvironments (LEXEN) pro-gram.

The Department of Energy(DOE) similarly has a widerange of programs that supportNASA space science activities.DOE has developed and sup-plied the radioisotope thermo-electric generators (RTGs) thathave enabled a wide range ofSolar System exploration mis-sions—from Apollo to Viking toVoyager, as well as the Galileoand Cassini-Huygens missions tothe outer planets. DOE hasdeveloped instruments and sen-sors for NASA’s space sciencemissions, particularly through itsLos Alamos and Lawrence-Livermore Laboratories. DOEand NASA have jointly studied amission to place high-energyparticle detectors in space aboard

satellites and the InternationalSpace Station, and the agenciesare working together on theGamma Ray Large Area SpaceTelescope (GLAST). Data fromDOE missions also support theInternational Solar TerrestrialPhysics program.

For its part, the Department ofDefense (DOD) has been a majordeveloper of high sensitivity,large-area infrared detector arraysneeded for many space sciencemissions. These and technologyfor large-area deployable opticalsystems are important for futurelarge telescopes in space. Throughits Naval Research Laboratory(NRL), DOD has contributedinstruments to space science mis-sions such as the ComptonGamma Ray Observatory (CGRO)and the Solar and HeliosphericObservatory (SOHO). In anotherarea, NASA and DOD cooperat-ed on the Clementine mission, aDOD-led joint mission that sur-veyed the Moon. Space science, inturn, contributes to some DODobjectives. For example, researchon solar flares, coronal mass ejec-tions, solar energetic particles, andthe terrestrial middle/upperatmosphere and magnetosphere isimportant for DOD command,control, and communications sys-tems. DOD and NASA haveestablished a partnership forexpanded cooperation on thespace environment.


In addition, NASA cooperates withthe National Oceanic and Atmo-spheric Administration (NOAA)and DOD by providing dataused for forecasting and under-standing the space environment.This effort is part of an intera-gency (NASA, NSF, NOAA,DOD, DOE, Department of theInterior [DOI]) national spaceweather program. NASA also worksclosely with the U.S. GeologicalSurvey of the Department of theInterior and the National Instituteof Standards and Technology(NIST, Department of Commerce).

The formation of technologydevelopment partnerships is animportant goal of the SpaceScience Enterprise. DOE, DOD,and other agencies such as NOAAshare many needs and capabilitieswith NASA, and NASA worksclosely with them to identifyopportunities for synergistic tech-nology development.

In the education area, NASAworks with NSF and theDepartment of Education to usespace science missions and pro-grams to contribute to science,mathematics, and technologyeducation and to share theexcitement of space science dis-coveries with the public. Forexample, we worked closely withthe Department of Education’sGateway to Educational MaterialsConsortium to develop an online

resource directory for space scienceeducation products.

Universities

From NASA’s very beginning,universities and university scien-tists have played a central role inthe planning and implementationof space science. University scien-tists serve on NASA study teamsand on key advisory committeesthat lay out long-range goals andobjectives, strategies, and priori-ties for space science. Universityscientists develop new approachesfor making critical measurements,serve as principal investigators forflight investigations, and carry out

the laboratory, theoretical, andcomputational studies required tointerpret data returned from spacescience missions.

Universities exist to create newknowledge and to transmit it. Theintellectual environment of univer-sities encourages innovation. Thus,university scientists carry out basicspace science research and otherlong-term research needed toinvestigate underlying principlesthat form the foundations of newtechnology. Universities have theprincipal responsibility for ensur-ing the steady stream of highlytrained and motivated peopleneeded to assure the future vitalityof the Space Science Enterprise.Space science programs are alsosignificant contributors to theongoing development of scientistsand engineers to meet largernational needs. Support fromNASA flight projects and researchgrants programs is an importantcontributor to maintaining theinfrastructure that permits this uni-versity participation.

The trend towards smaller, morefrequent, and lower cost missions,together with the advent ofadvanced communications andinformation systems technologies,has allowed universities to take ongreater responsibility for the design,development, and operation ofentire missions rather than just thedevelopment of individual instru-

partnerships | 101

From the

very beginning,

universities and

university scientists

have played a

central role in

the planning and

implementation

of space science.

ments on larger NASA-developedmissions. Easier electronic access toarchived data and new policies thatplace science data in the publicdomain as soon as possible are help-ing scientists and students at a widerange of institutions, including col-leges and smaller universities, toparticipate in the analysis of spacescience data.

For these reasons, the SpaceScience Enterprise is committedto a long-term partnership withour universities and their commu-nity of scientists and students.

Industry

Industry has made and will contin-ue to make significant contribu-tions to the planning, developmentand implementation of space sci-ence missions and research pro-grams. Industry has played acritical role in the design, engi-neering, manufacture, construc-tion, and testing of both largeand small space missions; in thedesign, development, testing,and integration of advancedinstruments; and in the develop-ment of advanced spacecraft,instrument, mission operations,and information system tech-nologies. Many industry capabil-ities have been developed forcommercial applications withDOD or NASA core technologysupport. The resulting extensive

space industry infrastructure isavailable for use for space sciencepurposes. The establishment ofpartnerships with industry allowsspace science to benefit from theexperience and capabilities of theindustrial sector.

As noted earlier, universities arenow partnering with industry toassume full responsibility for thedesign, development, and opera-tion of entire missions. With themore frequent flight opportuni-ties now being provided throughthe Explorer, Discovery, and

New Millennium programs,such partnerships are likely toplay an even more importantrole in the Space ScienceEnterprise in the future. Thereliance on the identification,development, and utilization ofadvanced technology to dramati-cally lower instrument, space-craft, and mission operationscosts requires strong partner-ships between industry and theEnterprise. Strong partnershipsare also important for facilitatingthe transfer of NASA-developedtechnology to industry andthereby realizing the commercialpotential of these technologiesand contributing to the long-term capability and competitive-ness of American industry.

Other Nations

The quest for knowledge does notrecognize national boundaries.Scientific expertise and capabilitiesare today more than ever distributedamong many nations. Commoninterests and limited resources virtu-ally dictate that nations cooperate inthe pursuit of common goals.Further, the Space Act specificallymandates a leadership role forNASA in promoting internationalcooperation in space research. Forall of these reasons, internationalcooperation is a fundamental aspectof virtually all Space ScienceEnterprise programs.


The Space

Science Enterprise

is committed

to the long-term

support of

university research

and to continuing

to work closely

with university

scientists and

students.

In some cases, other agencies andnations contribute to NASA-ledmissions. Foreign collaboratorscan join with U.S. teams to propose on NASA’s competitiveannouncements, and foreign agen-cies can negotiate to stake out rolesin U.S. strategic missions outlinedin this and future plans. To sup-port participation of U.S. investi-gators on foreign missions, themissions-of-opportunity option inExplorer and Discovery solicita-tions allows U.S. researchers tocompete for funding to provideinstrumentation or other contri-butions to missions developed byother countries or agencies.

International coordination ofstrategic planning poses a chal-lenge, but one that merits continu-ing attention. Each agency, whetherthe European Space Agency or thenumerous national agencies withwhich the Enterprise collaborates,has its own policies, planningcycles, funding processes, and sci-entific and technical priorities. Thecooperative environment is charac-terized by a complex, but healthy,blend of competition and coopera-tion. But there is a general recogni-tion, which NASA shares, that theopportunities for discovery outstripthe technical or financial resourcesof any individual player. As a result,

we are continuing to work to betterunderstand the goals and capabili-ties of our current and future part-ners, and we expect continuing

progress in maximizing all parties’returns on space science investmentthrough cooperative approaches tospace research.

partnerships | 103

The Student-Tracked Atmospheric Research Satellite for Heuristic International

Networking Experiment (STARSHINE) satellite leaves the cargo bay of the

Space Shuttle Discovery near the completion of the STS-96 mission. The

stowed Canadian-built remote manipulator system (RMS) arm is visible in the

foreground.


Sometime in the new century, humanity will know its place in the universe . . . and

will begin the challenge of writing its future in the history of the cosmos. Our tel-

escopes will have revealed in detail the most fundamental structures in nature:

the galaxies and the stars. Life-bearing planets—if they exist—will have been at

least tentatively identified. The next major step after detailed spectroscopy of

planetary atmospheres must be imaging of their surfaces: even a dozen or so

pixels in one direction across the face of an Earth-like planet orbiting a neighbor

star would reveal continents and weather patterns, as well as seasonal variations.

The optical designs for such an ambitious undertaking are not complicated, but

pose enormous engineering challenges.

104

a v i s i on o f t he f u tu reSection II-8Section II-8

If there are new fundamentalforces in nature that await discov-ery, we will have searched forthem within the gravitationalmaelstrom of massive black holesand in the earliest moments afterthe Big Bang. Our most powerfulx-ray interferometers will haverevealed the detailed structure atthe edges of black holes, and sub-millimeter interferometers willstudy the nature of gravity itselfwithin the fossil remnant of theprimordial fireball. The life storyof our Milky Way galaxy, as itsstars, planets, and life are built upfrom primordial atoms, will bemuch better understood.

Our most sophisticated robotswill have traveled to the darkouter reaches of the Solar Systemand plunged beneath the icy sur-faces of Europa and Titan, toseek out signs of organic activity,and perhaps, the struggles of lifeto maintain a foothold even inthese forbidding environments.Closer to home, Mars will havebeen surveyed in detail, with sur-

a vision of the future | 105

The two Mars 2003 rovers will extend the surface exploration begun by

Viking and Pathfinder. These new rovers will be able to travel 100 meters

per day, and will carry scientific instruments to determine the geological

context of rocks and soil and measure their chemical composition and fine

scale structure—even scraping the surface off rocks to expose their

unweathered interiors.

face samples returned to Earth fordetailed study. Programs to surveythe Red Planet for hidden resourcesof water will be well underway, aswell as an extended geological andmeteorological reconnaissance.

Our dynamic Sun and its sur-rounding planets will be under-stood as a system, including theeffects of the Sun’s life history onthe origin and continuation of lifein our Solar System. We will havegained the ability to predict andmanage the effects of solar variabil-ity on Earth and on humans andmachines in space. Our spacecraftwill have ventured beyond the bub-ble of solar wind that surrounds theSolar System to take our first stepsinto interstellar space.

Thanks to technologies emergingtoday, Earthbound humanity willbe able to participate actively in thegreat adventure of exploration.Our robotic emissaries to Mars andthe other worlds in our SolarSystem will possess increasinglypowerful capabilities for interac-tion with the home planet: virtualsight and sound, covering a broad-er spectrum of wavelengths and afar wider range of frequencies, willrecreate on Earth the experience ofexploring even the most forbiddingenvironments in space. All our cit-izens will become space explorers.

At the same time, a new generationof technology may permit more

individuals, for a greater variety ofreasons, to travel into space. It maybe that future steps in understand-ing our place in the cosmos will betaken by a partnership between

humans and machines in space.Complex optical systems, satellitesubsystems, and instruments maybe better updated, replaced, orrepaired by human partners than


The Hubble Space Telescope (HST) was designed to be a serviceable space-

craft. An astronaut uses the Power Ratchet Tool on an HST bay door while

replacing the observatory’s flight computer.

a vision of the future | 107

by even very advanced remotely-operated robots. Trained geologistson Mars may one day amplify thecapabilities of robotic collaboratorsused for large-area surveying andrapid reconnaissance by diggingbelow the surface of dry riverbedsand along the shorelines of ancientoceans in search of the history of abiology—if any—beyond Earth.

One day, after our first planet-finding observatories havebeamed back images of warm, wetworlds in orbit around neighbor-ing stars, our descendants willbegin to contemplate humanity’sdestiny of discovery beyond theSolar System.

The Solar and Heliospheric Observatory (SOHO) is a cooperative mission of ESA and NASA.

appendicesthe space science enterprise


science goals and missions

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Advanced Composition Explorer (ACE)—Measures energetic particles over a wide range of energy and mass, includ-ing the solar wind, solar particles, and the anomalous and galactic cosmic rays. The spacecraft measures the ele-mental and isotopic composition, from hydrogen to zinc, over the energy range of the cosmic rays from 100 eVto 500 MeV per nucleon for the charge range. ACE also provides realtime solar data from L1 for space weatherapplications.

Advanced Cosmic Ray Composition Experiment for the Space Station (ACCESS)—Attached payload for theInternational Space Station (ISS), it will measure the energy spectra from hydrogen to iron up to 1015 eV in orderto test the supernova origin theory of cosmic rays.

Advanced Satellite for Cosmology and Astrophysics (ASCA)—Japanese x-ray imaging spectrometer mission.Launched in 1993, it served double its expected lifetime before suffering debilitating damage after an intensesolar storm in July 2000.

Balloon Observations Of Millimetric Extragalactic Radiation and Geophysics (BOOMERANG)—Balloon-borne instru-ment that measured tiny variations in the cosmic microwave background radiation in order to detect the earli-est ancestors of today’s galaxies and to obtain indications that the geometry of the universe is flat, not curved.Jointly supported in the U.S. by NASA and NSF, BOOMERANG’s science team included members fromCanada, Italy, and the United Kingdom.

Cassini-Huygens—International mission involving NASA, the European Space Agency (ESA), the Italian SpaceAgency (ASI), and several separate European academic and industrial partners. The spacecraft carries a sophisti-cated complement of scientific sensors supporting 27 different investigations to probe the mysteries of theSaturn system. The mission consists of a NASA orbiter and ESA’s Huygens Titan probe.

Chandra X-ray Observatory (CXO)—High resolution imaging and spectroscopy mission to observe high-energycosmic events such as pulsars, supernova remnants, and black holes.

Cluster-2—ESA-led mission to study plasma structures, boundary layers, and energy transfer in three dimensionsboth within Earth’s magnetosphere and in the solar wind. The mission consists of four identical spacecraft, eachcarrying a full complement of fields and particles instrumentation, flying in tetrahedral formation.

Comet Nucleus Tour (CONTOUR)—Will study the aging processes of comets by examining diverse comet nuclei.Using an innovative trajectory design, this spacecraft will conduct close-up observations of two short periodcomets, Encke and Schwassmann-Wachmann 3, known from ground-based telescopic observations to have dif-ferent properties. An encounter with a third short period comet may be possible if sufficient resources remainfor an extended mission. This is the sixth Discovery mission.

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g lossa r y o f m i ss i onsSection A-2Section A-2

Compton Gamma Ray Observatory (CGRO)—Simultaneously obtained gamma ray measurements in an energyrange spanning six orders of magnitude from 30 KeV to 30 GeV. The mission made many fundamental discov-eries, including the discovery that gamma ray bursts are not galactic phenomena as previously believed, and thatactive nuclei of distant galaxies are dynamic and prolific emitters of enormous amounts of energy in high-ener-gy gamma rays. CGRO was deorbited in June 2000.

Constellation X (Con-X)—Mission to measure x-ray spectral lines in hot plasmas in order to determine the ele-mental composition, temperature, and velocity of the emitting matter. Objectives are to determine the flow ofgas in accretion disks around black holes in active galactic nuclei and in binary x-ray sources, measure the abun-dances of newly created elements in supernova remnants, and detect the influence of dark matter on the hotintergalactic medium in clusters of galaxies.

Cosmic Background Explorer (COBE)—Made precise measurements of the diffuse radiation with wavelengths betweenone micrometer and one centimeter over the entire celestial sphere, providing the first major step forward in space-based cosmology. COBE verified beyond all reasonable doubt that the cosmic microwave background has a cosmo-logical origin with tiny primordial perturbations from which large-scale structure in the present-day universe grew.

Cosmic Journeys—Proposed initiative to probe the most profound aspects of nature by using the universe as alaboratory. Within the Cosmic Journeys initiative, the Journey to a Black Hole probes more and more closelyto these extreme states of gravity. The Journey to Dark Matter seeks to unravel the mysterious nature of the uni-verse's “missing mass,” matter that we cannot see but know is present due to its gravitational effect on the visi-ble universe. And the Journey to the Beginning of Time explores the basic physics revealed in the first fewinstants of the universe, observing as far back as the first 10-32 seconds of time.

Deep Impact—Will determine the composition of pristine material in a comet nucleus. The spacecraft will senda 500 kilogram projectile into the nucleus of comet Temple 1 to excavate a crater deep enough to penetratebeneath the chemically-altered crust of the nucleus. Experiments on the spacecraft will then examine the prop-erties of the ejected material and observe the structure of the crater. The eighth Discovery mission.

Deep Space-1 (DS-1)—Technology validation mission that successfully validated solar electric propulsion and asuite of eleven other high priority spacecraft technologies.

Discovery Program—Level-of-effort program offering the scientific community regular opportunities to proposelow-cost deep space missions. Proposals are selected through competitive peer review, and selected teams haveresponsibility for implementation of the entire mission with minimal management oversight by NASA. Teamingarrangements among university, industry, and/or Government laboratories are encouraged. Discovery is the deepspace counterpart of the Explorer program.

glossary of missions | 115

Europa Orbiter—Will orbit this icy moon of Jupiter to determine if there is an underlying ocean, determine thethickness of the ice, and image the complex features on its icy surface. To determine if there is an ocean, the orbitermay use radar sounding, high-resolution laser altimeters, and free-falling probes equipped with seismometers. As apossible liquid water habitat in our Solar System, Europa is a critical target in the search for life beyond Earth.

Explorer Program—Level-of-effort program to provide frequent, low-cost access to space for physics and astron-omy investigations with small to mid-sized spacecraft. Investigations selected for Explorer projects are usually ofa survey nature, or have specific objectives not requiring the capabilities of a major observatory.

Extreme Ultraviolet Explorer (EUVE)—Explorer mission to survey the entire sky in the extreme ultraviolet, discov-er the brightest sources in the sky, and perform detailed spectroscopic investigations of the EUV radiation fromstars, nebulae, and galaxies. EUV radiation provides unique information concerning the physical and chemicalproperties of hot gas and plasma, and this information contributes to our knowledge of the matter and energyinteractions between stars and the interstellar medium.

Far Infrared and Submillimeter Telescope (FIRST)—ESA-led mission to study objects that radiate a substantialportion of their luminosity in this band. This includes detecting dusty galaxies at cosmological distances whenthe universe was less than one billion years old, regular spiral galaxies out to intermediate redshifts, and densemolecular clouds in our galaxy where stars are currently being formed. This will allow a study of the dynamicaland chemical evolution of galaxies and stars.

Far Ultraviolet Spectroscopic Explorer (FUSE)—Explorer mission conducting high-resolution spectroscopy of faintobjects at wavelengths from 905 to 1,195 angstroms. FUSE is probing the interstellar medium and galactic haloto measure the amount of cold, warm, and hot plasma in objects ranging from planets to quasars, including pri-mordial gas created in the Big Bang.

Fast Auroral Snapshot Explorer (FAST)—Small Explorer mission investigating the plasma physics of various auro-ral phenomena at extremely high time and spatial resolution. In polar orbit around Earth, the spacecraft carriesfields and particle instrumentation and features fast data sampling and a large burst memory.

Full-sky Astrometric Mapping Explorer (FAME)—Explorer to determine accurate positions, distances, and motions of 40million stars within our galactic neighborhood. FAME will measure stellar positions to less than 50 microarcseconds.

Galaxy Evolution Explorer (GALEX)—Explorer space ultraviolet mission to map the global history and causes ofstar formation over the redshift range 0<z<2, 80 percent of the life of the universe. GALEX will also explore theperiod over which galaxies have evolved dramatically, and the time that most stars, elements, and galaxy diskshad their origins.

Galileo Europa Mission (GEM)—Conducted the first comprehensive investigation of Jupiter, its magnetosphere,and its planet-size moons. On its arrival at Jupiter in December 1995, Galileo dropped an entry probe into theplanet’s atmosphere that returned the first direct measurements of the physical properties and chemical compo-sition of a gas giant planet. The orbiter discovered magnetic fields belonging to two of the satellites and has givenus close-up views of their surfaces. The two-year Galileo Europa Mission, which focused primarily on the satel-lite Europa, followed the prime Galileo mission.

Gamma Ray Large Area Space Telescope (GLAST)—Mission to observe the gamma ray energy range from 20 MeVto 300 GeV. Fifty times more sensitive than the EGRET instrument on the Compton Gamma RayObservatory, this instrument will observe thousands of active galactic nuclei (AGNs) and galactic sources,in addition to studying the more diffuse emissions from the Milky Way and other extended sources, includ-ing the diffuse all-sky background. A burst monitor will combine with the primary instrument to providegamma ray burst observations over a wide energy range. Cooperative with the Department of Energy,Japan, and Europe.


Genesis—Mission to determine accurately the chemical composition of the Sun. The spacecraft will expose pan-els of ultra-pure materials to the solar wind for two years to collect samples of the material that continuallystreams off of the Sun. These samples will then be returned to Earth for detailed laboratory analysis. The fifthDiscovery mission.

Geospace Electrodynamic Connections (GEC)—Near-term Solar Terrestrial Probe to help us understand how theinteraction of Earth with the interplanetary medium is conditioned by the presence of Earth’s atmosphere andits magnetic field. The mission will consist of four spacecraft following each other in the same orbit with vari-able spacing. The spacecraft generally fly in highly inclined elliptical parking orbits, but focused science cam-paigns will be conducted during satellite excursions down to 130 km or lower.

Geotail—ISAS-led mission to measure global energy flow and transformation in the magnetotail in order toincrease our understanding of fundamental magnetospheric processes.

Global Geospace Science (GGS)—Consists of the Wind and Polar spacecraft and is part of the U.S. contributionto the International Solar Terrestrial Physics (ISTP) program. The objectives of GGS are to measure, model, andquantitatively assess geospace processes in the Sun-Earth interaction chain.

Gravity Probe B (GP-B)—Will test Einstein’s general theory of relativity by measuring predicted dragging of space-time caused by the rotation of Earth. In order to make this measurement, GP-B will fly the world’s most per-fect sphere as a gyroscope. Also known as the Relativity Mission.

High Altitude Laboratory for Communications and Astrophysics (HALCA)—ISAS radio telescope in orbit that can becombined with large radio antennae on Earth to create a highly sensitive radio interferometric array. HALCAdemonstrated the feasibility of space-Earth arrays and observation of fine structure in radio galaxies, jets fromactive galactic nuclei, and supernova remnants.

High Energy Solar Spectrographic Imager (HESSI)—Explorer mission to study the basic physics of the particle acceler-ation and explosive energy release in solar flares. HESSI will carry an x-ray and gamma ray imaging spectrometerwith ultra-high temporal and spatial resolution in order to address the dynamic high-energy phenomena of the Sun.

High Energy Transient Explorer 2 (HETE 2)—Small mission to search for and detect the prompt x-ray and ultravi-olet emission that may accompany gamma ray bursts, as well as measure their position and send the informa-tion to ground based optical telescopes fast enough to allow the prompt optical emission to be detected as well.Cooperative mission with Japan and France.

Hubble Space Telescope (HST)—Explores the universe in the visible, ultraviolet, and near-infrared regions of theelectromagnetic spectrum. It is investigating the composition, physical characteristics, and dynamics of celestialbodies, examining the formation, structure, and evolution of stars and galaxies, studying the history and evolu-tion of the universe, and providing a long-term space-based research facility for optical astronomy. Cooperativewith ESA.

Imager for Magnetospheric to Aurora Global Exploration (IMAGE)—Explorer mission observing the response ofEarth’s magnetosphere to changes in the solar wind. The mission uses a combination of neutral atom, ultravio-let, and radio imaging techniques to provide global views of magnetospheric dynamics from a polar orbit.

Infrared Astronomical Satellite (IRAS)—Joint mission sponsored by the United Kingdom, the United States, andthe Netherlands, that mapped the sky at infrared wavelengths. Mission ended in 1983.

Infrared Space Observatory (ISO)—ESA follow-on to IRAS, explored the “cool and hidden” universe throughobservations in the thermal infrared between 3 and 200 microns. Its objectives included studies of brown dwarfsin our galaxy, protoplanetary disks around nearby stars, and the evolution of galaxies.


International Gamma Ray Astrophysics Laboratory (INTEGRAL)—ESA-led gamma ray observatory dedicated tospectroscopy and imaging in the energy range 15 keV to 10 MeV. In addition to two gamma ray instruments itwill have optical and x-ray monitors. This mission will study gamma ray lines from a range of astrophysicalsources, giving us information on nucleosynthesis in supernovae, the supernova history of the Milky Way, activegalactic nuclei, Seyfert galaxies, gamma ray bursts, and solar flare acceleration processes.

Keck Interferometer—Ground-based program to harness the twin 10-meter Keck telescopes together as a singleinstrument to search for planetary systems around other stars. This will complement and extend current ground-based planet detection capabilities and will serve as a prototype/test bed for future interferometers in space suchas SIM and Terrestrial Planet Finder.

Laser Interferometer Space Antenna (LISA)—Joint NASA-ESA mission to detect and study in detail gravitationalwave signals from massive black holes. This includes both transient signals from the terminal stages of binarycoalescence, which we will call bursts, and binary signals that are continuous over the observation period.

Living With A Star (LWS)—Program to develop the scientific understanding of aspects of the connected Sun-Earth system that directly affect life and society, with specific emphasis on understanding the factors thataffect human radiation exposure in space, the impacts of space weather on technical systems, and the effectsof solar variability on the terrestrial climate. Program elements include the Solar Dynamics Observatory(SDO), Radiation Belt Mappers (RBM), Ionospheric Mappers (IM), and Sentinels missions; a program ofspace environmental test beds; and an associated theory, modeling, and data analysis program.

Lunar Prospector—Conducted the first global survey of minerals on the surface of the Moon. Of particular inter-est for future human exploration of the Moon, Lunar Prospector detected indications of water ice in the per-petually dark bottoms of craters near the north and south poles. The third Discovery mission.

Magnetospheric Multiscale (MMS)—Near-term Solar Terrestrial Probe to characterize the basic plasma processesthat control the structure and dynamics of Earth’s magnetosphere, with a special emphasis on meso- and micro-scale processes. The mission will consist of a constellation of five identical spacecraft, each carrying fields andparticle instrumentation, flying in a variably spaced tetrahedron.

Magnetosphere Constellation (MagCon)—Solar Terrestrial Probe mission to understand the nonlinear dynamicresponses and connections within Earth’s magnetotail. It envisions placement of 50-100 autonomous micro-satellites, each carrying a minimum set of fields and particles instruments, into a variety of orbits.

Mars Exploration Program (MEP)—Program of successive Mars exploration missions to study: the solid planet, how itevolved, and what resources it provides for future exploration; the relationship to Earth’s climate change process; andthe potential for life there and elsewhere in the universe. The exploration series began with Mars Global Surveyor toorbit Mars and map the planet at infrared and visible wavelengths and observe selected areas at very high-resolution.MEP data will help us understand the geological and climatological history of the planet and lay the groundwork forchoosing the sites for surface missions. The subsequent two missions, Mars Climate Orbiter (MCO) and Mars PolarLander (MPL), were lost in 1999. Two geologic exploration rovers will be launched in 2003. Additional orbiter andlander missions to follow are under study.

Mars Pathfinder—Paved the way for future low-cost, robotic missions to Mars. The mission deployed a micro-rover named Sojourner on the Martian surface and acquired geological and meteorological data to characterizethe surface composition, geology, morphology, and atmospheric structure and conditions in Ares Valles. Thesecond Discovery mission.

Mercury Surface, Space Environment, Geochemistry, and Ranging (MESSENGER)—Will conduct a comprehensiveglobal survey of Mercury’s interior structure, surface composition, geological processes, tenuous atmosphere, andmagnetic field. The spacecraft will operate in orbit around Mercury for approximately one Earth year. The sev-enth Discovery mission.


Microwave Anisotropy Probe (MAP)—Follow-on to the successful COBE mission, MAP is a medium-class Explorerto measure the fluctuations in the cosmic microwave background with sufficient sensitivity to infer whether thefirst large structures in the universe after the Big Bang were galaxies or large clusters of galaxies. MAP’s observa-tions will also be sensitive enough to determine the total amount of dark matter in the early universe.

MUSES-C—ISAS-led mission to return a sample from an Earth-approaching asteroid. NASA will contribute amicrorover to explore the asteroid’s surface.

Near Earth Asteroid Rendezvous (NEAR)—In orbit around Earth-approaching asteroid Eros, NEAR is conductingthe first comprehensive investigation of the physical properties and mineral characteristics of one of these smallbodies. The first Discovery mission.

New Millennium Program (NMP)—Flight program to demonstrate new technologies in space.

Next Generation Space Telescope (NGST)—Follow-on observatory to HST to study the formation of galaxies atnear infrared wavelengths. It will combine a collecting area 10 times larger than HST with spectrometers opti-mized for near infrared radiation.

Planck—ESA-led third generation mission for exploring the fluctuations and anisotropies in the cosmicmicrowave background. Planck will improve previous measurements of the background by a factor of five.

Pluto/Kuiper Express—Miniaturized spacecraft to fly past the Pluto/Charon system and conduct a reconnaissanceof the only planet that has not been visited heretofore by a spacecraft. Following the Pluto/Charon encounter,the spacecraft may be redirected to survey a diverse collection of icy Kuiper Belt objects beyond the orbit ofNeptune.

Polar—Measures the entry of plasma into the polar magnetosphere, determines the ionosphere plasma outflow,obtains auroral images, and determines the energy deposited into the ionosphere and upper atmosphere. Polaris the second spacecraft in the Global Geospace Science program; it carries in situ fields and particles instru-mentation and a remote sensing imager.

Roentgen Satellite (ROSAT)—International collaborative mission to observe and map x-ray emissions from galac-tic sources. ROSAT studied coronal x-ray emissions from stars of all spectral types, detecting and mapping x-rayemissions from galactic supernova remnants, evaluating the overall spatial and source count distributions for var-ious x-ray sources. Additionally, ROSAT performed detailed studies of various populations of active galaxysources, conducting morphological studies of the x-ray emitting clusters of galaxies, and performing detailedmapping of the local interstellar medium. Cooperative with Germany and the United Kingdom.

Rossi X-ray Timing Explorer (RXTE)—Explorer mission to detect fluctuations in the x-ray intensity of cosmicsources that occur as rapidly as one millisecond or less. RXTE also studies the x-ray emission over a broad spec-tral band and a wide range of time scales in x-ray sources of all kinds. These capabilities enable astronomers tostudy accretion onto black holes in sources as different as x-ray binaries in our galaxy and the cores of activegalaxies and quasars millions of light-years away.

Solar and Heliospheric Observatory (SOHO)—ESA-led mission, component of the International Solar TerrestrialPhysics program, to study the internal structure of the Sun, its outer atmosphere, and the origin of the solarwind. The spacecraft carries instruments devoted to helioseismology, remote sensing of the solar atmosphere, andin situ measurement of solar wind disturbances.

Solar Anomalous and Magnetospheric Particle Explorer (SAMPEX)—A small Explorer mission to investigate the ori-gins and dynamics of solar energetic particles, heavy ions and electrons in the radiation belts, and anomalouscosmic rays. Its instruments observe the energy range from low energy solar particles to galactic cosmic rays.


Solar Dynamics Observer—First mission in the Living with a Star program, will observe the outer layers of theSun to determine the Sun’s interior dynamics and the origin of solar activity and coronal mass ejections.

Solar Probe—Will make the first measurements within the atmosphere of a star and will answer long-standing ques-tions about how and where the corona is heated and how the solar wind is accelerated. The spacecraft, which willcarry both imaging and in situ instrumentation, is targeted to pass within three solar radii of the Sun’s surface.

Solar Terrestrial Probes (STP)—Program of successive missions to perform a systematic study of the Sun-Earthsystem. Its major goals are to provide an understanding of solar variability on time scales that range from a frac-tion of a second to many centuries and to determine planetary and heliospheric responses to this variability. Theline begins with TIMED and is expected to continue near-term with Solar-B, STEREO, MagnetosphericMultiscale, Global Electrodynamic Connections, and Magnetospheric Constellation.

Solar Terrestrial Relations Observatory (STEREO)—Near-term Solar Terrestrial Probe to understand the origin anddevelopment of coronal mass ejections and trace the propagation and evolution of these disturbances from theSun to Earth. The mission will consist of two identical spacecraft, one leading and the other lagging Earth in itsorbit. Both spacecraft will carry instrumentation for solar imaging, for the tracking of solar ejection headingtoward Earth, and for in situ sampling of the solar wind.

Solar-B—ISAS-led mission to reveal the mechanisms that give rise to solar variability and study the origins ofspace weather and global change. The spacecraft, which will be placed in polar Earth orbit, will make coordi-nated measurements at optical, EUV, and x-ray wavelengths, and will provide the first measurements of the fullsolar vector magnetic field on small scales.

Space Interferometry Mission (SIM)—First optical interferometer in space and a technological precursor to theTerrestrial Planet Finder. SIM will allow indirect detection of planets through observation of thousands of starsand investigate the structure of planetary disks with nulling imaging.

Stardust—Will fly through the coma of comet Temple-II, collect a sample of cometary dust, and return the sam-ple to Earth for detailed laboratory analysis. A suite of remote-sensing instruments on the spacecraft will alsoinvestigate various physical and chemical properties of the comet. The fourth Discovery mission.

Stratospheric Observatory for Infrared Astronomy (SOFIA)—The next generation airborne observatory, SOFIA willprovide astronomers routine access to the infrared and submillimeter part of the electromagnetic spectrum. Itwill observe a wide range of phenomena, from the formation of planets, stars, and galaxies, to the evolution ofcomplex organic molecules in interstellar space. SOFIA will be ten times more sensitive than its predecessor, theKuiper Airborne Observatory, enabling observations of fainter objects and measurements at higher spectral res-olution. Cooperative with Germany.

Space Infrared Telescope Facility (SIRTF)—The fourth of NASA’s Great Observatories and a follow-on to theInfrared Astronomical Satellite (IRAS). SIRTF will perform imaging and spectroscopy in the infrared of the for-mation of stars and planets and will investigate the evolution of luminous galaxies.

Submillimeter Wave Astronomy Explorer (SWAS)—Small Explorer mission to study water and other similar mol-ecules throughout the galaxy. By measuring the density and distribution of these materials, the origin of ingre-dients necessary for life on Earth can be determined.

Swift Gamma Ray Burst Explorer—Explorer mission multiwavelength observatory for gamma ray burst astrono-my. Swift has a complement of three co-aligned instruments. Two are an x-ray and a UV/optical focusing tele-scope that will produce arcsecond positions and multiwavelength light curves for gamma ray burst (GRB)afterglow. A third instrument is a wide field-of-view coded-aperture gamma ray imager that will producearcminute GRB positions onboard within 10 seconds.


Terrestrial Planet Finder (TPF)—Currently envisioned as a long baseline infrared interferometer operating in the7-20 micron wavelength range for direct detection of terrestrial planetary companions to other stars and of spec-tral signatures that might indicate a habitable planet.

Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED)—Solar Terrestrial Probe to understandthe basic energetic and dynamics of the region where Earth’s atmosphere transitions to space. The spacecraft,which will fly in a 600-km circular Earth orbit, carries remote sensing instrumentation that will be supple-mented by significant collaborative investigations.

Titan Explorer—Mission to follow up on the scientific results at Titan expected from the Huygens probe andCassini orbiter. Detailed study of the organic-rich environment of Titan may be of key importance to studies ofpre-biotic chemistry.

Transition Region and Coronal Explorer (TRACE)—Small Explorer mission exploring the connection between fine-scale solar magnetic fields and the associated plasma structures. The spacecraft, which is in Sun-synchronousEarth orbit, carries a EUV/UV telescope for studies of fast-evolving dynamic phenomena on the Sun at one arc-second spatial resolution.

Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS)—An Explorer program-supported Mission ofOpportunity payload with the goal of assessing the geo-response to solar wind input. This will be accomplishedthrough analysis of the first stereo views of Earth’s magnetosphere, which will be provided by the flight of a pairof energetic neutral atom imagers on spacecraft with complementary orbits.

Ulysses—ESA-led mission to explore the high-latitude regions of the Sun and inner heliosphere. The spacecraftpasses over the Sun’s poles at a distance of about 2 AU and carries a variety of fields and particles instruments.

Voyager Interstellar Mission (VIM)—Combines the capabilities of the Voyager 1 and 2 spacecraft to explore theregion where the Solar System merges with the interstellar medium and to sample the local interstellar medi-um itself. These spacecraft are now both beyond the orbit of Pluto and are speeding toward the edge of theSolar System.

Wind—Part of the Global Geospace Science Program. The goals of Wind are to determine the characteristics ofthe solar wind upstream of Earth and to investigate basic plasma processes occurring in the near-Earth solarwind. It also carries two modest-sized gamma ray burst instruments for measuring the spectra and count ratetime-history of gamma ray bursts.

X-ray Multiple-mirror Mission (XMM)—ESA-led x-ray spectroscopy mission to determine the abundance and den-sity of iron, silicon, oxygen, and other heavy elements in stars and x-ray binaries. An understanding of the cyclingof these elements between stars and the interstellar medium is necessary for studying the formation of planets.

Yohkoh—ISAS-led mission to better understand the birth and evolution of various forms of solar activity, espe-cially solar flares. Because x-rays outline the magnetic structure of the Sun’s outer atmosphere, the spacecraft car-ries instrumentation that combines hard and soft x-ray imaging and spectroscopy.



Space Science Enterprise Concurrence

Edward J. Weiler, Associate AdministratorEarle K. Huckins, Deputy Associate AdministratorJeffrey D. Rosendhal, Assistant Associate Administrator for Education and Public OutreachAlan N. Bunner, Director for Structure and Evolution of the UniverseScott Hubbard, Director for Mars ExplorationAnne L. Kinney, Director for Astronomical Search for OriginsKenneth W. Ledbetter, Director for Flight ProgramsJay T. Bergstralh, Acting Director for Exploration of the Solar SystemGuenter R. Riegler, Director of Research Program ManagementPeter B. Ulrich, Director for TechnologyGeorge L. Withbroe, Director for Sun-Earth Connection

Enterprise Strategic Planning Working Group

Marc S. Allen (Lead), Assistant Associate Administrator for Strategic and International PlanningRuth A. Netting (Coordinator), Senior Program/Policy AnalystJay T. Bergstralh, Planetary Science Discipline ScientistHashima Hasan, Origins Discipline ScientistDonald Kniffen, High Energy Astrophysics Discipline ScientistMary M. Mellott, Geospace Discipline ScientistMichael A. Meyer, Astrobiology Discipline ScientistJeffrey D. Rosendhal, Assistant Associate Administrator for Education and Public OutreachHarley A. Thronson, Decade Planning Team Senior Science ManagerGiulio Varsi, Senior TechnologistJoel Vendette, Senior Graphic DesignerHope Kang, Technical Writer/Editor

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en te rp r i se concu r rence aSection A-3Section A-3

Acknowledgments

The NASA Office of Space Science would like to express appreciation for the work undertaken by the membersof our science community to help formulate program options and prepare this Strategic Plan.

Galveston Strategic Planning Workshop Participants, November 2-4, 1999

David Akin, University of MarylandJoseph Alexander, National Research CouncilLouis Allamandola, NASA Ames Research CenterMarc Allen, NASA HeadquartersChristine Anderson, Air Force Research LabCharles Beichman, NASA Jet Propulsion LaboratorySteven Benner, University of FloridaJay Bergstralh, NASA HeadquartersRichard Binzel, Massachusetts Institute of TechnologyDavid Black, Lunar and Planetary InstituteBaruch Blumberg, NASA Ames Research CenterAlan Boss, Carnegie InstitutionAlan Bunner, NASA HeadquartersJames Burch, Southwest Research InstituteMike Calabrese, NASA Goddard Space Flight CenterWendy Calvin, U.S. Geological SurveyRobert Carovillano, Boston CollegeAndrew Christensen, The Aerospace CorporationChris Chyba, SETI InstituteDavid DesMarais, NASA Ames Research CenterMichael Drake, University of ArizonaCharles Elachi, NASA Jet Propulsion LaboratoryGordon Garmire, Pennsylvania State UniversityPaula Frankel, NASA ConsultantRobert Gehrz, University of MinnesotaHashima Hasan, NASA HeadquartersIsabel Hawkins, University of California at BerkeleyJohn Hayes, Woods Hole InstitutePaul Hertz, Naval Research LaboratoryRobert Hoffman, NASA Goddard Space Flight CenterSteven Horowitz, NASA Goddard Space Flight CenterRichard Howard, NASA HeadquartersScott Hubbard, NASA Ames Research Center

enterprise concurrence and acknowledgments | 123

and acknow ledgmen ts

Galveston Strategic Planning Workshop Participants (continued)

Kenneth Johnston, U.S. Naval ObservatoryAnne Kinney, NASA HeadquartersDonald Kniffen, NASA HeadquartersEdward (Rocky) Kolb, Fermi National Accelerator LaboratoryDavid Lavery, NASA HeadquartersKenneth Ledbetter, NASA HeadquartersTom Levenson, Levenson ProductionsMolly Macauley, Resources for the FutureBruce Margon, University of WashingtonDavid McComas, Los Alamos National LaboratoryRalph McNutt, Johns Hopkins UniversityMary Mellott, NASA HeadquartersRichard Mewaldt, California Institute of Technology Michael Meyer, NASA HeadquartersDaniel Mulville, NASA HeadquartersFirouz Naderi, NASA Jet Propulsion LaboratoryRuth Netting, NASA HeadquartersMarian Norris, NASA HeadquartersKathie Olsen, NASA HeadquartersJames Papike, University of New MexicoE. Sterl Phinney, California Institute of Technology Carl Pilcher, NASA HeadquartersThomas Prince, California Institute of TechnologyStephen Prusha, NASA Jet Propulsion LaboratoryDouglas Richstone, University of MichiganGuenter Riegler, NASA HeadquartersJeffrey Rosendhal, NASA HeadquartersRobert Semper, ExploratoriumWilliam Smith, Association of Universities for Research in AstronomyLarry Soderblom, U.S. Geological SurveyCarrie Sorrels, NASA HeadquartersSteven Squyres, Cornell UniversityDouglas Stetson, NASA Jet Propulsion LaboratoryEllen Stofan, University of London and NASA Jet Propulsion LaboratoryKeith Strong, Lockheed Research LaboratorySimon Swordy, University of ChicagoHarvey Tananbaum, Smithsonian ObservatoryHarley Thronson, NASA HeadquartersJames Trefil, George Mason UniversityPeter Ulrich, NASA HeadquartersMeg Urry, Space Science Telescope InstituteSamuel Venneri, NASA HeadquartersRichard Vondrak, NASA Goddard Space Flight CenterEdward Weiler, NASA HeadquartersGeorge Withbroe, NASA HeadquartersMaria Zuber, Massachusetts Institute of Technology


Space Science Advisory Committee

Steven Squyres (Chair), Cornell UniversityDavid Black (former Acting Chair), Lunar and Planetary InstituteChristine Anderson, Air Force Research LaboratoryRoger Blandford, California Institute of TechnologyAndrew Christensen, Aerospace CorporationAlak Das, Air Force Research LaboratoryDavid DesMarais, NASA Ames Research CenterMichael Drake, University of ArizonaAlan Dressler, Carnegie ObservatoriesJack Farmer, Arizona State UniversityRobert Gehrz, University of MinnesotaDaniel Hastings, U.S. Air ForceDavid Hathaway, NASA Marshall Space Flight CenterIsabel Hawkins, University of CaliforniaKlaus Keil, Hawaii Institute of Geophysics and PlanetologyEdward Kolb, Fermi National Accelerator LaboratoryMolly Macauley, Resources for the FutureBruce Margon, University of WashingtonDaniel McCleese, NASA Jet Propulsion LaboratoryRichard Mewaldt, California Institute of TechnologyJames Papike, University of New MexicoDouglas Richstone, University of MichiganWilliam Smith, Association of Universities for Research in AstronomyC. Megan Urry, Space Telescope Science InstituteRichard Vondrak, NASA Goddard Space Flight CenterMaria Zuber, Massachusetts Institute of Technology

Sun-Earth Connection Advisory Subcommittee

Andrew Christensen (Chair), Aerospace CorporationCynthia Anne Cattell, University of MinnesotaAntoinette Broe Galvin, University of New HampshireGeorge Gloeckler, University of MarylandJoseph Bearak Gurman, NASA Goddard Space Flight CenterRobert Hoffman, NASA Goddard Space Flight CenterMary Hudson, Dartmouth CollegeStephen Kahler, Air Force Research Laboratory/VSFSPaul Kintner, Cornell UniversityMartin Lee, University of New HampshireDavid McComas, Southwest Research InstituteRalph McNutt, Applied Physics LaboratoryJan Josef Sojka, Center for Atmospheric and Space ScienceTheodore Tarbell, Lockheed Martin Advanced Technology CenterMichelle Thomsen, Los Alamos National LaboratoryHunter Waite, Southwest Research InstituteRaymond Walker, University of California


Sun-Earth Connection Roadmap Team

Keith Strong (Chair), Lockheed-Martin Advanced Technology Center.James Slavin (Co-Chair), NASA Goddard Space Flight CenterJames Burch, Southwest Research InstituteCharles Carlson, University of California at BerkeleyAndrew Christensen, The Aerospace CorporationPatrick Espy, Embry-Riddle UniversityAntoinette Galvin, University of New HampshireGeorge Gloeckler, University of MarylandRaymond Goldstein, NASA Jet Propulsion LaboratoryLeon Golub, Smithsonian Astrophysical ObservatoryMichael Gruntman, University of Southern CaliforniaDavid Hathaway, NASA Marshall Space Flight CenterIsabel Hawkins, University of California at BerkeleyJ. Todd Hoeksema, Stanford UniversityLynn Kistler, University of New HampshireJames Klimchuk, Naval Research LaboratoryRobert Lin, University of California at BerkeleyBarry Mauk, Applied Physics LaboratoryRalph McNutt, Applied Physics LaboratoryRichard Mewaldt, California Institute of TechnologyThomas Moore, NASA Goddard Space Flight CenterArthur Poland, NASA Goddard Space Flight CenterKarel Schrijver, Lockheed-Martin Advanced Technology CenterDavid Siskind, Naval Research LaboratoryJan Sojka, Utah State UniversityHarlen Spence, Boston UniversityJeffery Thayer, Stanford Research InternationalRichard Vondrak, NASA Goddard Space Flight Center

Astronomical Search for Origins and Planetary Systems Advisory Subcommittee (Origins)

Alan Dressler (Chair), Carnegie ObservatoryDavid Black (former Chair), Lunar and Planetary InstituteLouis Allamandola, NASA Ames Research CenterCharles Beichman, NASA Jet Propulsion LaboratoryOmar Michael Blaes, University of CaliforniaPeter Bodenheimer, University of California, Lick ObservatoryAdam Seth Burrows, University of ArizonaWilliam Cochran, University of Texas at AustinHeidi Hammel, Space Science InstituteKenneth Johnston, U.S. Naval ObservatoryHarold McAlister, Georgia State UniversitySusan Neff, NASA Goddard Space Flight CenterRobert Noyes, Smithsonian Astrophysical ObservatoryMarcia Jean Rieke, University of ArizonaSteven Ruden, University of California at IrvineCharles Steidel, California Institute of TechnologyHervey (Peter) Stockman, Space Telescope Science Institute


Structure and Evolution of the Universe Subcommittee

Bruce Margon (Chair), University of WashingtonJohn Armstrong, NASA Jet Propulsion LaboratoryArthur Davidsen, Johns Hopkins UniversityGordon Garmire, Pennsylvania State UniversityNeil Gehrels, NASA Goddard Space Flight CenterJacqueline N. Hewitt, Massachusetts Institute of TechnologyMarc Kamionkowski, California Institute of TechnologyCharles R. Lawrence, NASA Jet Propulsion LaboratoryDaniel Lester, University of TexasDan McCammon, University of WisconsinPeter Michelson, Stanford UniversityBradley Peterson, Ohio State UniversityE. Sterl Phinney, California Institute of TechnologySimon Swordy, University of ChicagoHarvey Tananbaum, Center for AstrophysicsDaniel Weedman, Pennsylvania State UniversityAndrew Wilson, University of MarylandFiona Harrison (Executive Assistant to Chair), California Institute of Technology

Solar System Exploration Subcommittee (SSES)

Michael Drake (Chair), University of ArizonaChristopher Chyba (former Chair), SETI InstituteDavid Aikin, University of MarylandRichard Binzel, Massachusetts Institute of TechnologyJeffrey Cuzzi, NASA Ames Research CenterCharles Elachi, NASA Jet Propulsion LaboratoryJack Farmer, Arizona State UniversityCaitlin Griffith, Northern Arizona UniversityDavid Grinspoon, Southwest Research InstituteBruce Jakosky, University of ColoradoStamatios Krimigis, Johns Hopkins UniversityLaurie Ann Leshin, Arizona State UniversityWilliam McKinnon, Washington UniversityKenneth Nealson, NASA Jet Propulsion LaboratoryCarolyn Porco, University of ArizonaSean Solomon, Carnegie Institution of WashingtonDavid Stevenson, California Institute of TechnologyEllen Stofan, NASA Jet Propulsion LaboratoryMichael Zolensky, NASA Johnson Space Center


Jupiter as seen in October 2000 by the Cassini spacecraft as itspeeds by on its way to Saturn. Jupiter’s moon Europa, seen asthe bright point at the right, casts its shadow on the planet.

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the space science enterprise - NASA40 years, space probes and space observatories have played a cen-tral role in this fascinating process. Today, NASA addresses these four profound