The Search for Extra Terrestrial
Intelligence
The SETI Institute is a private, nonprofit
organization whose mission is to explore, understand and explain the origin, nature and prevalence of life in the
universe.
The Institute comprises 3 centers, the Center
for SETI Research, the Carl Sagan Center for the Study of Life in the Universe and the Center for Education and
Public Outreach.
Founded in November 1984, the SETI Institute
began operations on February 1, 1985. Today it employs over 150 scientists, educators and support staff. Research
at the Institute is anchored by two centers. Dr. Jill Tarter leads the Center for SETI (Search for Extraterrestrial
Intelligence) Research as Bernard M. Oliver Chair for SETI. Dr. David Morrison is the Director for the Carl
Sagan Center for the Study of Life in the Universe. Edna DeVore leads our Center for Education and Public
Outreach.
While interest in the question of
extraterrestrial life is at least as old as historical civilizations, the modern SETI era can be defined as
beginning in 1959. In that year, Cornell physicists Giuseppi Cocconi and Philip Morrison published an article in
Nature in which they pointed out the potential for using microwave radio to communicate between the
stars.
A young radio astronomer, Frank Drake, had
independently reached the same conclusion, and in the spring of 1960 conducted the first microwave radio search for
signals from other solar systems. For two months Drake aimed an 85-foot West Virginia antenna in the direction of
two nearby Sun-like stars. His single-channel receiver was tuned to the "magic" frequency of the 21 cm (1,420 MHz)
line of neutral hydrogen, a spot on the radio dial also favored by Cocconi and Morrison because of its astronomical
significance. While he didn't detect any signal of extraterrestrial origin, Drake's Project Ozma spurred the
interest of others in the astronomical community, most immediately the Russians.
In the 1960's, the Soviet Union dominated SETI,
and it frequently adopted bold strategies. Rather than searching the vicinities of nearby stars, the Soviets used
nearly-omnidirectional antennas to observe large chunks of sky, counting on the existence of at least a few very
advanced civilizations capable of radiating enormous amounts of transmitter power.
During the 1970's, many radio astronomers
conducted searches, using existing antennas and receivers. Some of the efforts, employing improved technology, have
continued to the present time. Foremost among these are the Planetary Society's Project META, the University of
California's SERENDIP project, and a long-standing observing program at Ohio State University.
By the late-1970s, SETI programs had been
established at NASA's Ames Research Center and at the Jet Propulsion Laboratory (JPL) in Pasadena, California.
These groups arrived at a dual-mode strategy for a large-scale SETI project. Ames would examine 1,000 Sun-like
stars in a Targeted Search, capable of detecting weak or sporadic signals. JPL would systematically sweep all
directions in a Sky Survey. In 1988, after a decade of study and preliminary design, NASA Headquarters formally
adopted this strategy, and funded the program. Four years later, on the 500th anniversary of Columbus' arrival in
the New World, the observations began. Within a year, Congress terminated funding.
With NASA no longer involved, both researchers
and interested members of the public saw a diminished chance to answer, within their lifetimes, the profound
question addressed by SETI. Consequently the SETI Institute is endeavoring to continue this large-scale program
with private funding.
Project Phoenix concentrated efforts on that
component of the NASA SETI project known as the Targeted Search. Its strategy was to carefully examine the regions
around 1,000 nearby Sun-like stars. The world's largest antennas were used, committing observing time for
SETI.
Project Phoenix was orders of magnitude more
comprehensive than any experiment yet performed. Frequently, the successful attainment of an elusive goal requires
nothing less than a systematic and thorough effort. That was the philosophy behind, and the promise of, Project
Phoenix.
Other long-term SETI projects are underway.
Among these is Project SERENDIP operated by the University of California, Berkeley at the Arecibo telescope. A
second major project is conducted in Australia by an independent group, the SETI Australia Centre at the University
of Western Sydney. The Australians have bought the SERENDIP technology to run their own 58 million-channel
experiment on the Parkes radio telescope. The popular screensaver/distributed computing software project
known as SETI@home, run by UC Berkeley, has brought SETI to millions.
In the meantime the SETI Institute has been
focusing on the future. In a joint project with UC Berkeley, it is building a SETI-dedicated array of telescopes
that will equal a 100-meter radio telescope, the Allen Telescope Array. It is the forerunner of other larger radio
astronomy arrays planned for later in the decade. It is possible that as telescope and SETI technology advance it
may be possible to detect intelligence not by directed message but by the same kind of 'noise' we accidentally
broadcast to the cosmos via radio, television and radar signals. SETI truly is a long-term
project.
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