AAAC Presentation

JWST Status

Eric P. SmithJWST Program Scientist

11-October-2005 2AAAC Presentation

Topics

• JWST Cost Growth

• Science Assessment Team Findings and

Program Response

• JWST Plans

11-October-2005 3AAAC Presentation

Recent Programmatic Changes

~$1B net cost growth• ~$180M at NGST and ~$35M at subs

– Reevaluation of I&T effort (metrology, GSE)– Additional launcher-related testing requirements– Reallocation of technical resources (e.g., mass and power budgets)

among observatory elements

• ~$85M in instruments and related elements• ~$160M of recommended added contingency funding• ~$600M for 22 month launch slip to 6/2013

– Launch vehicle uncertainty and lack of TAA– Budget profile limitations in FY06 and 07– Schedule risk reduction (negotiated w/ NGST)

• Technology maturation efforts remain on schedule

11-October-2005 4AAAC Presentation

Science Assessment Team (SAT) Findings

• “… the scientific case for the JWST mission has become even stronger since its highest ranking by the Decadal report in 2000.”Retain current 6.5 meter primary aperture Retain current instrument complementPriority on unique capabilities, i.e., performance

longward of 1.7 microns, given the limitations of other future ground and space-based assets

• Use prioritization as a guide to reduce cost and risk

11-October-2005 5AAAC Presentation

SAT-Endorsed Changes

SAT Recommendation Program ResponseDe-emphasize or eliminate low-priority instrument capabilities

See next chart

Simplify Integration & Test Revising Integration & Test plan (e.g., “cup-up” testing) ~$130M & 3 months savings (TBR)

Eliminate 1 µm encircled energy requirement

Eliminate Level 1 requirement (possible degradation of imaging performance at shortest wavelengths)enables simplified I&T (see above) reduces mirror polishing schedule risk

Relax scattered light requirement Change cleanliness levels (acceptable potential reduction in sensitivity)enables “cup-up” layout, simplified I&T (see above)

Relax optical stability requirement Change tstab = 30 days to tstab = 14 days (reduce observing efficiency ~1%)reduces telescope backplane development risk

Relax/eliminate anisotropy requirement Eliminate Level 2 Point-Spread-Function anisotropy requirement (no expected science impact)reduces telescope development risk

Maintain mission lifetime goal No change

11-October-2005 6AAAC Presentation

SAT-Endorsed Changes:Science Instruments

SAT Recommendation Program ResponseMaintain short wavelength ( < 1.7 µm) instrument capabilities, but eliminate JWST architecture (ISIM level and above) requirements for testing/verification of these capabilities

Revising Integration & Test and verification plans to comply with recommendation (fewer reverifications of lowest priority science modes, elimination of potentially infeasible tests)specific cost and schedule benefits TBD

Maintain current MIRI coronography capabilities

No change

Retain single channel tunable filter Eliminate short wavelength portion of tunable filter (loss of lowest priority science capability)saves 80kg; improves mass marginreduces complexity; enhances likelihood of on-time delivery of FGS

11-October-2005 7AAAC Presentation

Moving Forward

Consult scientistsregarding JWST’s

scientific significance,prioritize JWST’s

capabilities

Revise mission development plan

Preliminary Final

Independent Assessment

Formulate budget

May’05 Apr’06

Science Assessment Team (SAT)

NASA’s Independent Program Analysis Office (IPAO)

11-October-2005 8AAAC Presentation

JWST Replan

• It’s not over…– Additional study of I&T and verification plan forecast with

ultimate conclusion around April 06

• Will this happen again?– History of replans

• 8m 6m diameter requirement, Fall 2000• Replan I, Fall 2002• Replan II, Summer 2005• (see chart 9)

• Will the science change?– No, first light goal combined with NAS decadal position prohibits

significant changes in observatory

11-October-2005 9AAAC Presentation

HST Spending History

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

0246810121416

Years-to-Launch

Fraction of Phase A-D Costs

HST (no servicing costs)

JWST (Projection)

11-October-2005 10AAAC Presentation

JWST Program Today

• Early emphasis on vigorous technology development to retire risk– Pacing items (primary mirror, detectors) already in Phase C/D and flight

production

• ~$820M (~20% of Phase A through D total) invested so far

today

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019

Concept Development Design, Fabrication, Assembly and Test

FormulationAuthorization

Non-Advocate Review(NAR)-Program Commitment-

Launch

science operations ...

Initial Confirmation Review (ICR)

Phase A Phase B Phase C/D Phase E

Formulation Implementation …

11-October-2005 11AAAC Presentation

SummaryActions being taken to address JWST cost and schedule changes

– Current estimated cost, inception through launch $3.7B– Current estimated cost, Oct’06 through launch $2.9B

• Science assessment complete– JWST reconfirmed as mission of paramount significance and priority– Scientific capabilities prioritized– Recommendations provide some cost savings and significant risk reduction; added

flexibility for program management

• Preliminary replanning complete, FY07 budget adjusted and submitted– Science assessment recommendations embraced, being implemented– Launch in June 2013

• Preliminary stage of independent assessment found program work plan fundamentally sound, but likely to need more time and money

Detailed replanning will be complete by April 2006– Fully implement embraced SAT changes– Follow-up independent review and assessment– Forms basis for FY08 budget development

AAAC Presentation

Mission ObjectiveStudy the origin and evolution of galaxies, stars and

planetary systems Optimized for infrared observations (0.6 – 28 m)

Organization– Mission Lead: Goddard Space Flight Center– International collaboration with ESA & CSA – Prime Contractor: Northrop Grumman Space Technology

– Instruments: – Near Infrared Camera (NIRCam) – Univ. of

Arizona– Near Infrared Spectrograph (NIRSpec) –

ESA– Mid-Infrared Instrument (MIRI) – JPL/ESA– Fine Guidance Sensor (FGS) – CSA Description

– Deployable telescope w/ 6.5m diameter segmented adjustable primary mirror

– Cryogenic temperature telescope and instruments for infrared performance

– Launch NET June 2013 on an ESA-supplied Ariane 5 rocket to Sun-Earth L2

– 5-year science mission (10-year goal)

James Webb Space Telescope (JWST)

www.JWST.nasa.gov

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019

Concept Development Design, Fabrication, Assembly and Test

FormulationAuthorization

NAR Launch

science operations ...

ICR(PNAR)

Phase A Phase B Phase C/D Phase E

Telescope

Primary Mirror (PM)

Cold, space-facing side

SunshieldSpacecraft Bus

Warm, Sun-facing side

Instrumentmodule

scale:

1 meter