British scientist Stephen Hawking is worried that any extraterrestrial life we find is likely to be a creature out of the movie Predator – not ET.
But many fellow scientists disagree, and won't stop looking for alien life beyond Earth.
In a new Discovery Channel documentary to be aired in May, renowned astrophysicist Dr. Hawking suggests that with 100 billion galaxies in the universe it seems “perfectly rational” that aliens exist. While they are most probably microorganisms or basic animals, he suggests the threat posed by intelligent life forms, if they exist, could make reaching out to them “a little too risky.”
“We only have to look at ourselves to see how intelligent life might develop into something we wouldn’t want to meet. I imagine they might exist in massive ships, having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they can reach,” he said. “If aliens ever visit us, I think the outcome would be much as when Christopher Columbus first landed in America, which didn’t turn out very well for the native Americans.”
Among many astronomers and scientists, however, Hawking's conclusion seems sensational and counterproductive. Hollywood and science fiction novelists have been wrestling with this "friend or foe" question for decades. But the technology used to detect new planets – and thus our ability to find alien life – has increased in recent years and will likely continue to make drastic improvements in the next five to 10 years.
As the possibility of discovering extraterrestrial life catches up with fiction, the question may become more pertinent.
But most scientists argue that humans should be prepared for and welcome any potential encounters.
“Ignoring the possibility [alien life] and hiding your head in the sand, waiting for them to find us certainly isn’t a scientifically intelligent way to proceed or a good cultural way to anticipate something like that either,” says Mary Voytek, senior scientist for astrobiology at NASA. “Our approach to it has been to be prepared. We’re not going to get caught, say like the native Americans when Columbus came to their shores. We’ve been actively listening and hopefully we get some information before any eventual encounter ever happens.”
A new planet found every day
Scientists first discovered an extrasolar planet in 1992. Now Martha Haynes, an astronomer at Cornell University in Ithaca, New York, says that just 18 years later astronomers are arriving at a point where the available technology combined with new search techniques is allowing astronomers to find more new planets than ever before. She adds that technology will only continue to improve and will likely see major breakthroughs in the next five to 10 years.
“We are in a position to learn a lot more about what else might be out there in the cosmos and in particular we’re on the verge of finding … planets which support the kinds of conditions which might allow life as we know it to exist,” says Dr. Haynes, who adds that a new planet is discovered almost every day.
Most of the new planets that have been discovered since 1992 tend to be more like Jupiter and closer to their star, so it’s highly unlikely that they support intelligent life like that found on Earth.
Techniques for detecting Earth-like planets are improving though, says Steve Rawlings, head of astrophysics at Oxford University in England. In 2020, for example, a new generation of radio telescopes will be able to rule out or whether the nearest 100 or so planets have intelligent life like our own, says Professor Rawlings.
“Most calculations suggest that we would be unlikely to find anything that close to us in the universe,” he says. Although the number of astronomers searching for extraterrestrial life constitute a relatively small fraction of the field, he adds, “I certainly think that most astronomers think that work is valuable, particularly as instruments become more sensitive.”
Though most scientists agree with Hawking that the vast majority of alien life will not be intelligent, most argue that the potential benefits of not reaching out far outweigh the risks of doing nothing.
U text, don't you?
There remain logistical questions about how we would communicate with extraterrestrials. Communications technology on Earth has evolved rapidly in just the last 50 years, for example, so if aliens are just 50 years ahead of human technology we may have a hard time connecting.
“Aliens that we contact are likely to be far in advance of us, and may well have the capability to find out a great deal about us even if we don't talk formally with them, so I think talking would be OK. Moreover, it could be very interesting,” David E. Pritchard, a professor of physics at the Massachusetts Institute of Technology, writes in an e-mail to the Monitor.
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(Editor's note: The original version misspelled Stephen Hawking.)