The design for the new telescope arose from series of marathon brainstorming sessions between the institute's astronomers, University of California at Berkeley scientists and some of the tech industry's most respected big thinkers.
Most powerful radio telescopes rely on one giant antenna, the power of which increases with the diameter of it dish. Hewlett-Packard's former head of research and development Bernard M. Oliver, who died in 1995, imagined building a telescope that he called a "Cyclops," or a giant eye made from an array of smaller antennas. At the time he came up with the idea several decades ago, hooking all those antennas up to computers would have been enormously expensive. But with the price of electronics falling rapidly over the past few years, that is no longer an issue.
The Allen Telescope Array, named after its most generous donor, Paul Allen, will be made up of 350 or more small silver aluminum dishes that will be spread out over 90 acres in a randomized pattern. It is being built in the northern tip of California in the most other worldly of landscapes -- a field filled with desert bushes and lava patches and surrounded by snow-capped mountains.
Many of the components used in the new telescope are basic off-the-shelf parts, making it significantly cheaper and easier to build than its counterparts. While a large telescope might cost $200 million to build, Davis said, the SETI one will cost about $35 million and will by some measures be even more powerful and sophisticated.
"This thing ultimately is made up of 350 souped-up backyard antennas," Shostak said. About a dozen of the antenna dishes are operational now. By the end of the summer, the number is expected to grow to 30, reaching 42 by the end of the year. The array is expected to be completed in 2008.
Glamorized in the movie "Contact," which starred Jodie Foster, and other Hollywood movies as fast-paced and exciting, the search for extraterrestrial intelligence is in reality a lesson in patience.
SETI astronomers begin with lists of planets ranked by how hospitable they may be to life as we know it. A number of criteria are factored in, such as their age, how close they may be to sun-like stars, whether they have the potential to hold liquid water.
The astronomers then go to each of these "hab stars," or habitable environment stars, one by one and scan them for any transmissions across all frequencies.
Until the Allen Telescope Array began operating, the search for alien life was conducted on a part-time basis. The scientists would usually borrow time on other telescopes, record the data and then analyze it for months afterwards using computer systems. If some out-of-the-ordinary signals were detected astronomers often had to wait for another turn to gather more data, a time-consuming process.
Now SETI can scan places 24 hours a day, seven days a week and run the analysis in real time.
Since the spring of 1960, when a then-young astronomer named Francis Drake first pointed a telescope at some nearby stars and listened for extraterrestrial signals, SETI scientists have analyzed 1,000 stars. Over the next two decades, the Allen Telescope Array hopes to be able to study 1 million more. But with an estimated hundred billion stars in the Milky Way galaxy and a hundred billion galaxies in the universe, to say there is a lot more work to be done is an understatement.
On a recent morning a few hours after dawn, Davis walked briskly around the high-desert field, checking to make sure the saucer-shaped antenna dishes were being installed correctly. He then returned to his office to sit in front of a computer and coordinate with his colleagues in SETI's Silicon Valley office to remotely point the telescope every which direction and began the task of trying to differentiate between man-made phenomena and possible alien ones.
And so it will go for the next year, decade, century, millennium or longer. Davis knows that even if other civilization exists somewhere out there, the chances of finding it in his lifetime are remote. "If after a thousand years we can't confirm a signal, it certainly says something." Davis paused, frowning. "Maybe they are quieter than we are. Or maybe they aren't there at all."
