Looking for life in the cosmic haystack
Politics and recession have crimped budgets and the search for life in outer space
ET might be phoning, but do we care enough to take the call? Operating on money and equipment scrounged from the public and from Silicon Valley millionaires, and on the stubborn strength of their own dreams, a band of astronomers recently restarted one of the iconic quests of modern science, the search for extraterrestrial intelligence – SETI, for short – which had been interrupted last year by a lack of financing.
Early in December, a brace of 42 radio telescopes, known as the Allen Telescope Array, nestled at Hat Creek, Calif., in the shadow of Lassen Peak, came to life and resumed hopping from star to star in the constellation Cygnus, listening for radio broadcasts from alien civilisations. The lines are now open, but with lingering financial problems, how long they will remain that way is anybody’s guess.
These should be boom times for those seeking out aliens, or at least their radio proxy.
Astronomers now know that the galaxy is teeming with at least as many planets – the presumed sites of life – as stars. Advanced life and technology might be rare in the cosmos, said Geoffrey W Marcy, the Watson and Marilyn Alberts in the Search for Extraterrestrial Intelligence professor at the University of California, Berkeley, “but surely they are out there, because the number of Earthlike planets in the Milky Way galaxy is simply too great.”
A simple ‘howdy,’ a squeal or squawk, or an incomprehensible stream of numbers captured by one of antennas here at the University of California’s Hat Creek Radio Observatory would be enough to end our cosmic loneliness and change history, not to mention science. It would answer one of the most profound questions humans ask: Are we alone in the universe?
Despite decades of space probes and billions of Nasa dollars looking for life out there, there is still only one example of life in the universe: the DNA-based web of biology on Earth. “In this field,” said Jill Tarter, an astronomer at the SETI Institute in Mountain View, Calif., the “number two is the all-important number. We count one, two, infinity. We’re all looking for number two.”
But the story of SETI is the story of a dream deferred by politics, a lack of money and the technological challenges of searching what astronomers call ‘the cosmic haystack’: 100 billion stars in the galaxy and 9 billion narrow-band radio channels on which aliens, if they exist, might be trying to hail us.
Politics and the recession have crimped astronomers’ budgets and left the institute’s scientists with a kind of siege mentality. Last spring, the University of California ran out of money to run the Hat Creek observatory, forcing the Allen telescopes into hibernation. Continuing the search depends on a delicate deal to share the telescopes with the Air Force, which wants to use them to track satellites and space junk. No federal funds have been spent searching for radio signals from outer space since 1993.
Eerily quiet corridors
A recent visit to the SETI Institute’s Mountain View offices found many of the cubicles empty and the corridors eerily quiet. Last summer, as the Allen telescopes slumbered, weeds grew around them.
The story begins with a young radio astronomer named Frank Drake, who pointed an antenna from the National Radio Astronomy Observatory in Green Bank, W.Va., at a pair of stars in 1960, wondering if he could make contact with anything or anyone. All he got was static, but the hook was set.
In 1971, Nasa held a workshop led by Barney Oliver, the research chief of Hewlett-Packard, that concluded the best way to find extraterrestrials was with a $10 billion array of giant radio telescopes called Cyclops. The price tag – as well as the subject – set off alarm bells that still reverberate. In 1978, Sen William Proxmire of Wisconsin, an outspoken critic of what he considered wasteful government spending, awarded one of his infamous ‘Golden Fleece’ awards to the hunt for aliens, and in 1993, a Nasa-sponsored survey for signals from 1,000 nearby stars was cancelled by Congress. With the help of friends like Oliver in the Silicon Valley, Tarter and her colleagues took up the search. As the director of SETI research at the institute, Tarter, 67, has become the public face of the cause, and she was consulted by the actress Jodie Foster about her portrayal of Ellie Arroway, a radio astronomer who finds a signal, in the movie ‘Contact.’
Tarter was recruited in 1976, when, as a postdoctorate student at Berkeley, she read the Cyclops report, a rite of passage for most alien-oriented astronomers. “You didn’t have to ask a priest or philosopher about life in the universe,” Tarter said. But she realised she was in the first generation that could conduct experiments about it. A half-century and roughly 2,000 stars later, humanity is still officially alone.
Drake is undaunted, noting that there are 100 billion suitable stars in the galaxy. His personal estimate, based on an equation he invented in 1961, is that there are 10,000 technological civilizations in the galaxy, one per million stars. “I’ve known all along we have to look at a million stars,” he said. Now a cherubic 81, Drake is a professor at the University of California, Santa Cruz, and a former chairman of the SETI Institute.
The Allen Array, which was designed to find Drake his million stars, is named after Paul G Allen, the Microsoft founder and philanthropist, who put up $25 million to get the project going. Jointly owned and operated by the University of California, Berkeley, and the SETI Institute, it was to consist of 350 antennas, 20 feet in diameter, that were to be mass-produced like satellite dishes.
The full array would be able to map a swath of sky several full moons in diameter in only 10 minutes, or the whole sky in a night – of great interest to astronomers and, as it turned out, to the military. But Allen’s contribution was only enough to build 42 antennas, which started operating in 2007. The astronomers say that another $55 million would complete the array, but there have been no volunteers yet.
The project got a lift in 2009 when Tarter won a $100,000 prize and ‘One Wish to Change the World’ at the TED conference – short for Technology, Entertainment and Design – in Long Beach, Calif. Her talk there began, “The story of humans is the story of ideas.” It elicited a donation of valuable equipment from Dell and Intel. The project got another lift – mainly psychological – when Nasa’s Kepler spacecraft, which is beaming back news about the patch of Cygnus that it surveys, published its first list of 1,035 exoplanet candidates.
