Unit 9 Seminar: Life Out There? Evelyn I. Milian Instructor 2011

Unit 9 Seminar: Life Out There?

Evelyn I. MilianInstructor

2011

Life Out There?SETI: Search for ExtraTerrestrial Intelligence

Since the beginning of civilization, people have wondered if we are alone in the universe or whether there is intelligent life somewhere else. (NASA, 2009)

2011 2Evelyn I. Milian - Instructor

Egyptians Medieval Times CopernicusAstronomer; 1473 – 1543


Since the mid-1950s, American scientists have been searching actively for extraterrestrial life with all of the most advanced astronomical tools.

For a long time, the U.S. government funded this research, called the Search for Extra-Terrestrial Intelligence (SETI).

Most SETI projects involve surveying the sky with massive radio and optical telescopes that are designed to listen and watch for signals that are made up of non-random patterns.

The assumption scientists use is that, if there is life beyond this planet, we may be able to find evidence of it by looking for unusual patterns coming from space.

2011 3Evelyn I. Milian - Instructor

http://setiathome.ssl.berkeley.edu/

http://history.nasa.gov/


FIELD TRIP!!!

Visit the following websites about this topic and come back to share your comments:

http://history.nasa.gov/seti.html

http://science.nasa.gov/science-news/science-at-nasa/1999/ast23may99_1/

http://history.nasa.gov/garber.pdf

http://setiathome.ssl.berkeley.edu/ 2011 Evelyn I. Milian - Instructor 4

http://history.nasa.gov/seti.html



http://history.nasa.gov/garber.pdf



What do you think scientists expect to find through SETI and SETI@home?

Why did Congress canceled the SETI program?

2011 Evelyn I. Milian - Instructor 5


In the late twentieth century, scientists converged upon the basic idea of scanning the sky and "listening" for non-random patterns of electromagnetic emissions such as radio or television waves in order to detect another possible civilization somewhere else in the universe.

In late 1959 and early 1960, the modern SETI era began when Frank Drake conducted the first such SETI search at approximately the same time that Giuseppe Cocconi and Philip Morrison published a key journal article suggesting this approach. (NASA, 2009)


Drake

Cocconi

Morrison


NASA joined in SETI efforts at a low-level in the late 1960s and early 1970s. Some of these SETI-related efforts included Project Orion, the Microwave Observing Project, the High Resolution Microwave Survey, and Toward Other Planetary Systems.

On Columbus Day in 1992, NASA initiated a formal, more intensive, radio astronomy SETI program.



The SETI program included two main components:

1. The Targeted Search

2. The All-Sky Survey

NASA managed the 'Targeted Search’, which was conducted at the over 300-meter radio telescope in the Arecibo Observatory in Puerto Rico, and was meant to focus on emissions from those nearby stars that scientists viewed as most promising for ETI (Extraterrestrial Intelligence) signals.

JPL (Jet Propulsion Laboratory) scientists, contractors of NASA, managed the 'All-Sky Survey’, JPL used its 'Deep Space Network' Dish to scan the entire Milky Way.



Why was SETI canceled?

On Columbus Day in 1992, NASA initiated a formal, more intensive, radio astronomy SETI program. Less than a year later, however, Congress abruptly canceled the program. Why? (NASA, 2009)

While there was and still is a debate over the likelihood of finding intelligent extraterrestrial life, virtually all informed parties agreed that the SETI program constituted worthwhile, valid science.

Yet, fervor over the federal budget deficit, lack of support from other scientists and aerospace contractors, and a significant history of unfounded associations with nonscientific elements combined with bad timing in fall 1993 to make the program an easy target to eliminate. (Garber, 1999)



SETI CONTINUES….

While greatly disappointed after NASA's cancellation of the SETI program, program personnel moved quickly and with resolve to continue SETI with private funding.

A number of scientists moved over to the non-profit SETI Institute which had acted as a NASA contractor for a number of years and although contingent to restrained private funding were able to continue the 'Targeted Search' at the Arecibo Observatory calling it 'Project Phoenix’.

Project Phoenix continues to this date.



SETI CONTINUES….

The 'All-Sky Survey' conducted with JPL's equipment was discontinued and was replaced by the less comprehensive observations that the SETI Institute could make contingent upon the vagaries of continued private funding.

While the cancellation of SETI program did not end all research on this area, it significantly limited the amount of science that researchers could accomplish.



THE SCIENCE OF SETI

The first step in assessing scientific value is usually peer review.

Do other knowledgeable scientists agree that the researcher's questions and methods of inquiry reflect proper scientific method?

If so, then the results are usually accepted and further research is encouraged.

NASA's SETI program generally received high marks on this score.



THE SCIENCE OF SETI

In 1982, the journal 'Science' published a petition put together by the renowned american astronomer, astrophysicist and cosmologist Carl Sagan that was signed by numerous prestigious scientists, including biologists and biochemists such as Stephen Jay Gould, David Baltimore and Linus Pauling.



THE SCIENCE OF SETI

A 1991 National Academy of Sciences (NAS) working paper done by the National Astronomy Panel concluded that even though SETI was not formally a radio astronomy program, it contained exciting, valid science.

The Panel therefore recommended establishing a complementary university-based research program to help NASA develop search algorithms and signal processors.



SKEPTICS

When the discussion stayed on a serious scientific level, the SETI program was viewed favorably in large measure because those scientists who thought about such matters had reached a strong consensus years ago about the how, where and when to search for signals.

Still, scientific skeptics tried to play on the fact that nobody had any solid idea about what the odds were of an intelligent civilization existing elsewhere in the cosmos.

Even if there was intelligent life elsewhere, what was the possibility that these beings could beam a message to us that we could pick-up and understand?

If we on Earth were just guessing at these probabilities or the probabilities were low, why bother looking at all?



TODAY

SETI efforts continue; recently there has been increased public interest in the possibility of extraterrestrial life.

NASA's discoveries of a Martian meteorite that may contain fossils of microorganisms and of possible water on Jupiter’s moon Europa, as well as the successful Mars Pathfinder mission (1996-97) and the movie ‘Contact’ (1997), have all increased excitement in space exploration.


http://upload.wikimedia.org/wikipedia/en/7/75/Contact_ver2.jpg


TODAY

NASA has begun a new program called ‘Origins' that aims to build on the Hubble Space Telescope's dramatic successes by building a series of even more sophisticated space observatories to search for planets beyond our solar system.

The Origins program also aims to include various other means to answer fundamental questions about how the universe began and whether there is life beyond Earth.

It is unlikely, however, that radio astronomy SETI efforts will be incorporated into the Origins program in the near future.



THE SCIENCE OF SETI@HOME

SETI (Search for Extraterrestrial Intelligence) is a scientific area whose goal is to detect intelligent life outside Earth. One approach, known as radio SETI, uses radio telescopes to listen for narrow-bandwidth radio signals from space. Such signals are not known to occur naturally, so a detection would provide evidence of extraterrestrial technology.

Radio telescope signals consist primarily of noise (from celestial sources and the receiver's electronics) and man-made signals such as TV stations, radar, and satellites. Modern radio SETI projects analyze the data digitally. More computing power enables searches to cover greater frequency ranges with more sensitivity. Radio SETI, therefore, has an insatiable appetite for computing power.




Previous radio SETI projects have used special-purpose supercomputers, located at the telescope, to do the bulk of the data analysis. In 1995, David Gedye proposed doing radio SETI using a virtual supercomputer composed of large numbers of Internet-connected computers, and he organized the SETI@home project to explore this idea. SETI@home was originally launched in May 1999.

ET, phone SETI@home!

Last week nearly 300,000 home computers contributed 1100 years of CPU time to the search for extraterrestrial life. (Phillips – NASA, 2010)

SETI@home – a free screen-saver program that sifts through data from the Arecibo Observatory (P.R.) in search of extraterrestrial transmissions – was made available on-line for the general public on May 17, 1999. The program is easy to download and install. Downloading requires about 5 minutes over a 28.8Kbps modem.

"Installing it was no problem," said Science@NASA artist Duane Hilton, a self-professed technophobe. "If I can do it anyone can!"



WHAT DO YOU THINK?

“With SETI@home, anyone, anywhere could be the person who helps discover intelligent life elsewhere in the universe. This is a grand experiment - in science, in technology and in society - and a global cooperative effort at the frontiers of knowledge." - Louis Friedman, Executive Director of the Planetary Society

Do you believe SETI and SETI@home are worthwhile projects? Why?

What outcome(s) do you think will results from SETI and SETI@home?





The Arecibo Observatory, the world’s largest radio telescope, completely fills a natural karst valley in the Caribbean island of Puerto Rico. The 1000 ft. diameter reflector is so big that scientists actually run around it for exercise. Many discoveries are credited to the great dish, including the first known extrasolar planets orbiting a neutron star and thousands of new galaxies that delineate the structure of the local Universe.



Download SETI@home from UC Berkeley!









REFERENCES

Garber, S. – National Aeronautics and Space Administration (NASA) (2009). SETI: The Search for ExtraTerrestrial Intelligence. http://history.nasa.gov/seti.html

Garber, S. J. (1999). Searching for Good Science: The Cancellation of NASA’s SETI Program. Journal of the British Interplanetary Society, Vol. 42, pp. 3-12. http://history.nasa.gov/garber.pdf

Phillips, T. – National Aeronautics and Space Administration (NASA) (2010). ET, phone SETI@home. http://science.nasa.gov/science-news/science-at-nasa/1999/ast23may99_1/

Trefil, J. & Hazen, R. M. (2011). The Sciences An Integrated Approach. Sixth Edition. John Wiley & Sons, Inc. NJ, USA.


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Unit 9 Seminar: Life Out There? Evelyn I. Milian Instructor 2011