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- ITHACA, NY
(UPI) - Having
sent out a calling card 25 years ago, and then realizing
the wait for an
answer would take thousands of years, the search for
extraterrestrial life
changed from one of "calling" to one of
"listening."
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- On Nov. 16, 1974, astronomers decided to send a simple
"greeting" into deep space from the Arecibo radio antenna in
Puerto Rico. "It was really a symbolic gesture," said Donald
Campbell, a former Arecibo researcher and now a professor of astronomy
at Cornell University. "We wanted to show that it could be
done."
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- The simply encoded message contained a map of our solar
system,
information about the chemistry of life on Earth and pictures of
human
beings. It was beamed in the direction of the M13 globular cluster,
a
grouping of thousands of stars 25,000 light years away.
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- These days, however,
few scientists are interested in
sending such messages. Instead,
they're engaged in various "listening"
projects, hoping that
radio signals from an intelligent civilization will
reach
Earth.
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- The
main reason, Campbell explained, is one of time:
Send a signal out, and
you have to wait thousands of years for a reply.
A listener, however,
can be eternally optimistic: An extraterrestrial message
could arrive
at any moment. The quest is called SETI the "Search for
Extraterrestrial Intelligence."
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- The largest and most
sophisticated search is Project
Phoenix, conducted by the SETI
Institute in Mountain View, Calif. The project
uses the Arecibo antenna
and other large receivers in the United States
and Britain. Project
Phoenix computers can monitor 28 million frequencies
at a time. Since
1995, it has targeted about 500 sun-like stars and will
examine another
500 before the current phase of the project is completed
in
2001.
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- Other searches include SERENDIP, being carried out by
astronomers at the University of California in Berkeley; and Project BETA,
organized by the privately funded Planetary Society.
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- The success of the movie
"Contact," adapted
from a book by astronomer Carl Sagan,
indicates that the general public
is fascinated by the search for life
beyond Earth. For many scientists,
however, SETI is seen as a
"fringe" activity.
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- Astronomers often point out that with a hundred billion
stars in our galaxy, there could well be life beyond our solar system but,
because of the vast distances involved, the chances of detection are slim.
"This is very much a back-burner activity" for most astronomers,
said Seth Shostak of the SETI Institute.
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- Still, if contact with an alien
civilization is made,
it would forever alter mankind's view of its
place in the cosmos.
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- "It would make the Renaissance look like small
potatoes,"
said Shostak. "We'll know we're not the only game
in town."
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