The Allen
Telescope Array (ATA) in 2008.
A back-bencher US senator decided to get himself some
publicity in 1991 and chose NASA's SETI (Search for
Extraterrestrial Intelligence) program as an easy
target. Saying it was a waste of money to look for little
green men, he got the program canceled.
This occurred despite the fact that the project, the
High Resolution Microwave Survey, was a thoroughly
refereed program with support across the scientific
spectrum and its budget was actually very modest.
In the wake of this sad affair, non-governmental
and amateur programs arose to continue the effort.
Most of the SETI efforts rely on public donations to
fund at least some of what the NASA could have done.
This included the Phoenix
project that rose from the ashes of the NASA program.
In addition, several amateur groups have sprung
up to carry out their own SETI programs. As it is in
astronomy,
it is quite feasible for amateurs to make significant
contributions in this area. The prime challenge of SETI
is to monitor a vast number of channels in a vast number
of directions. The more people that are looking, the
better the chance of finding something.
The conventional SETI technique is to use radio telescopes
to monitor the water hole, i.e. the radio frequency
range between the emissions of hydrogen (H) and hydroxyl
(OH) where cosmic background noise and absorption in
the atmosphere are both low. Also, since these emissions
are common throughout the universe, it would be a logical
range for other civilizations to choose to send out
a signal.
An exciting new approach is to look in the visible
spectrum for coherent light signals. This is based on
the assumption that laser light could be used by other
civilizations for communications.
A unique and exciting project for amateurs is SETI@home.
Data from radio telescopes will be distributed over
the Internet to thousands of participants who will have
special programs running as screensavers that analyze
the data when the computers are not otherwise in use.
For an introduction to SETI and how you can get
involved, see Larry
Klaes page at COSETI
entitled So
You Want to "Get Into" SETI.
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