Landing on comets, flying past Pluto and putting a robot on Mars: some of the things that make governments, entrusted with spending taxpayer money wisely feel jittery.
An even bigger gamble for the public purse – one that even risks derision – involves the search for little green men. Although the idea appeals to a great number of people, in austerity-ridden times it is likely to be regarded as politically reckless.
Fortunate then, that a rich science enthusiast has stepped into the breach. Last week billionaire Russian internet entrepreneur Yuri Milner announced he is putting cash on the table to re-launch and revitalise the Search for Extra-terrestrial Intelligence (SETI), a science project that began more than half a century ago.
Milner is giving $100 million to fund Breakthrough Listen over the next decade. The new effort will be far more intensive than to date, including time on two of the world’s most powerful radio telescopes: the Robert C. Byrd Green Bank Telescope in West Virginia US and the CSIRO Parkes Telescope in New South Wales, Australia.
In comparison to SETI, the new search will be 50 times more sensitive, thanks to leaps in signal-processing power, and cover 10 times more sky.“We’ve no idea what we might find,” Martin Rees, the UK’s astronomer royal and adviser to the project,” told Science|Business. “We don’t know if anything is out there. The hope is to detect something, but even if we do, we may not be able to make any sense of it.”
Even if scientists pick up incomprehensible signals that, “would be a huge discovery,” Rees said. The signals may come from a planet where the most advanced forms of intelligence are machines. “It’s a reasonable guess because in a century or two, artificial intelligence is expected to supersede humans here,” said Rees, who is also a fellow and emeritus professor of cosmology at Cambridge University.
Goldilocks
There are potentially habitable, Earth-like planets out there in space, but no one is sure if any of them possess the vital “Goldilocks” quality or being neither too hot nor too cold, but with conditions which are just right to support life.
Can we rule out discovering life in our solar system? “I think pretty much, don’t you?” Rees replied.There are not many candidates for life in the Milky Way, he said. “Mars doesn’t look too promising. There might be life swimming under the ice on Europa [Jupiter’s moon] or on Saturn’s Enceladus [another moon]. But I wouldn’t hold my breath. Any intelligence will probably be something like 10 light-years away.”
Joining Rees in Breakthrough Listen is a coterie of leading experts in the field including Frank Drake of Cornell University, who initiated the search for radio signals from aliens in 1960. Also backing the projects are cosmologist Stephen Hawking; Peter Worden, former director of the NASA Ames Research Laboratory, home of the Kepler telescope; Geoffrey Marcy of the University of California, Berkeley; Dan Werthimer, director and chief scientist of the SETI Research Center at the University of California; Andrew Siemion, also of Berkeley; and Ann Druyan, a co-author of the recent “Cosmos” television programme and widow of famed astronomer and author Carl Sagan.
Citizen science
In common with SETI, amateur star-gazers will be invited to help analyse the vast amount of collected data, which in keeping with Milner’s Silicon Valley values, will be freely available to anyone, Rees said.
It sounds like a complicated task for volunteers, but Rees strongly supports it. “It may help. If you analyse data manually, you might miss something,” he said.
He gives a recent example. “The Kepler telescope [owned by NASA] recently looked for planets by measuring the brightness of stars. Their signal for a planet was if you could see a star’s light dimming a little: this would tell us there’s a planet orbiting and casting its shadow on the star, you see.”
It was an amateur astronomer that stumbled upon a new discovery. “He found a planet which orbits around two stars, not one, as originally identified by scientists.”
Message in a bottle
Instead of donning headphones and listening out for signals, should scientists send a message of their own into the cosmic silence?
A second, smaller initiative, Breakthrough Message, is putting up $1 million for a competition, open to all-comers, to determine what kind of interstellar greeting card Earth should post.
It is an idea that stirs controversy. Some scientists like Hawking, who was on the platform with Rees at the launch of Breakthrough Listen at the Royal Society in London, warn against attracting the attention of intelligent company. This is an unwarranted fear, Rees believes.
“I find it hard to take these concerns seriously,” he said. “If there are aliens that are more advanced than us, they’d know something about us already, wouldn’t they? They’d know we’re here.”
There is an International Institute of Space Law, but currently no body of law or ethics around sending signals into space. In theory, anyone with a powerful enough antenna could be broadcasting right now. In the past NASA has beamed a Beatles song into space, while nachos manufacturer Doritos transmitted one of its adverts.
What dispatch would Rees like to post? “I haven’t really thought of it in any detail. It would need to be a message that’s as culture-independent as possible. You’d have to ask, what would they want to know?”
However, distance and time differences make conversation and companionship with extra-terrestrials unlikely. “You can rule out back and forth repartee,” Rees said.