SAN JOSE, California — They don't hold out much hope that Vulcans will arrive on our doorsteps intoning "live long and prosper," but many astronomers believe that making radio contact with an alien civilization would fundamentally alter humanity for the better. For fifty years, however, they have searched the sky for signs of intelligent beings elsewhere in the universe with no result. Some think it's time to start sending our own messages to the stars in hope that someone up there will reply.
So-called "active SETI" is controversial. Astrophysicist Steven Hawking famously cautioned against shouting out our presence into the void, saying that first contact "… didn't turn out very well for the Native Americans." In response to such concerns, the nonprofit SETI Institute held one of the first public debates on the wisdom of active SETI, at the AAAS annual meeting.
The chances of someone picking up the message are better than ever. Recent data "encourages those who are optimistic about life in the universe," said astrobiologist David Grinspoon of the Planetary Science Institute at a 12 February news conference. Scientists now believe one in five sun-like stars have planets with conditions suitable for life, he reported. And research on extreme organisms on Earth, which eke out existence in the most challenging of environments, suggests that life could survive in even more unlikely places. The more common life in general is, Grinspoon suggested, the more probable that some of it has evolved intelligence and perhaps the ability to communicate.
SETI astronomer Douglas Vakoch argued that the time has come to stop waiting for some other galactic civilization to establish contact with us and make the first gesture ourselves. After all, if no one is transmitting messages, we don't have much chance of hearing one. "Sometimes we talk about SETI as an attempt to join the galactic club," Vakoch said, "but no one ever talks about paying our dues or even submitting an application."
The first step, Vakoch said, is to send out a signal that an extraterrestrial version of the SETI project could pick up. The message, he suggested, could be sent in the spare time of the Arecibo telescope in Puerto Rico, which astronomer Frank Drake used to send a coded message to a distant star cluster in 1974.
Speaking out against blabbing our presence to the stars was David Brin of Futures Unlimited in San Diego. Perhaps we haven't heard from alien civilizations because we're listening in the wrong place or with the wrong technology, he said. Perhaps they are waiting for us to make the first move. Or, maybe there's a more sinister explanation. Given the lack of any solid data, he said, SETI scientists' assumption that any galactic civilization capable of communicating with us would be benign is a dangerous one.
Brin called for a self-imposed halt on active broadcasts until there can be a global discussion of the potential risks and benefits. He compared this to the pause biologists placed on genetic engineering in the early 1990s to discuss the technology's risks and best practices. This moratorium, Brin said, ultimately resulted in better and safer research. In particular, he called for the inclusion of historians who could caution astronomers about the potential dangers of making contact. Here on Earth, Brin said, no first contact between peoples has ever been painless, even when there have been the best of intentions.
"'I Love Lucy' is washing over the shores of a new planet out there on average once a day."
Seth Shostack
The possible benefits of making contact far outweigh the risks, said Seth Shostak, a senior astronomer at SETI. He argued that any alien civilization that could reach us to do us harm would be more than capable of detecting us already. Any extra terrestrial with technology just a few centuries beyond ours, he estimated, could find us based on the radio and television broadcasts we have inadvertently beamed into space since the mid-20th Century. "Our leakage is 70 light years into space," he said. "'I Love Lucy' is washing over the shores of a new planet out there on average once a day."
Brin called Shostak's claims assertions based on assumptions rather than data. "We are learning so much so fast," Brin said. "Fifteen years ago we knew of no planets outside our solar system — now it's thousands." Wouldn't make more sense, he asked, to pause and learn more before doing something that could change the fate of the world forever? Perhaps the risks of shouting into the interstellar jungle are small, but they are real, he said. "What we are saying is 'Let's talk about it.'"The possible benefits of making contact far outweigh the risks, said Seth Shostak, a senior astronomer at SETI. He argued that any alien civilization that could reach us to do us harm would be more than capable of detecting us already. Any extra terrestrial with technology just a few centuries beyond ours, he estimated, could find us based on the radio and television broadcasts we have inadvertently beamed into space since the mid-20th Century. "Our leakage is 70 light years into space," he said. "'I Love Lucy' is washing over the shores of a new planet out there on average once a day."
Today's debate is just one step in an ongoing exploration of actively pinging the galaxy. The SETI Institute plans to hold a day-long workshop Saturday at its Mountain View campus. The meeting is slated to include the perspectives of historians and religious scholars, according to SETI Institute CEO David Black, who organized the meeting. The objective, Black said, is to start figuring out how to regulate and plan any active SETI efforts. Currently, he said, there's no law preventing people from renting time on a radio telescope and "firing off a signal." The potential impact of announcing ourselves to the galaxy is immense, he said, and he expects a long debate. If we decide to pick up the phone, the next question is what we want to say.
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