August 23, 2010
Alien Life Could Be Mechanical, Not Biological
The alien life forms that we are searching for might not be "life forms" after all--they could well be sentient machines, according to a senior astronomer at the SETI Institute.
In an article published online in the journal Acta Astronautica, SETI's Seth Shostak writes, "Our experiments to find extraterrestrial life are predicated on the assumption that it is most likely to be found on so-called 'habitable worlds.' These are planets and moons where surface liquid water exists, and atmospheres of light gases are found. Our searches presume that life on other worlds has a biochemistry at least somewhat similar to our own."
"While these postulates might be our best guide for finding biology, they could be misleading us in the search for extraterrestrial intelligence (SETI)," he adds. "Timescale arguments suggest that shortly after a sentient species invents the technology for communication, it develops synthetic intelligence. Consequently, SETI's targeted searches of star systems that might have habitable planets in the conventional sense may be chasing a very short-lived prey."
In an interview posted to the BBC News website, Shostak said that many of his fellow researchers aren't necessarily concerned with what type of extraterrestrial life they discover, but that there is an existing assumption that aliens would be overtly biological in nature--and thus would need to be on a planet that needs somewhat similar to our own--that could be unnecessarily limiting their search.
"If you look at the timescales for the development of technology, at some point you invent radio and then you go on the air and then we have a chance of finding you," he told BBC Science and Technology Reporter Jason Palmer. "But within a few hundred years of inventing radio--at least if we're any example--you invent thinking machines"¦ So you've invented your successors and only for a few hundred years are you... a 'biological' intelligence. I think a synthetic intelligence--the thinking machines--might be a little more difficult to find than the biological ones."
Shostak's article, entitled "What ET will look like and why should we care," was published on the Acta Astronautica website on July 7. It was also presented at the 60th International Astronautical Congress (IAC), held in Daejeon, Republic of Korea in October 2009.
Image Caption: Artist concept of an extrasolar planet. Credit: NASA
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