There is little doubt that our capacity to sense the most ethereal, fleeting phenomena in the cosmos is at an all time high. But there seems to be a fine line between acknowledging that exciting possibility and falling prey to the kind of hubris that some of our precursors fell prey to. Naturally, we say, this is the most special time in human existence, if we can only expand our minds and our efforts then all may be revealed!
Of course, none of us can know for sure which way this will all go. Caleb A. Scharf is director of astrobiology at Columbia University. He is author and co-author of more than scientific research articles in astronomy and astrophysics. For many years he wrote the Life, Unbounded blog for Scientific American.
Follow Caleb A. Scharf on Twitter. Already a subscriber? Sign in. Thanks for reading Scientific American. These two unpalatable options are pretty much the only possibilities, according to the new study. That's because evolution is predictable, and alien biospheres should thus produce intelligent creatures much like us, with technological prowess and an ever-increasing need for resources.
But the fact that we haven't run across E. Life on Earth has exploited just about every conceivable niche, tolerating extremes of temperature, salinity, pH and pressure. Conway Morris makes the case that Earth life thus exists close to the physical and chemical limits of life anywhere.
Further, Conway Morris says, evolution operates predictably, producing relatively predictable outcomes. These two suppositions argue that alien life, if it exists, should be fairly similar to terrestrial life, generating intelligent beings much like us.
These aliens may look unfamiliar, but any differences would be skin-deep. Other researchers have raised this same point. The eminent physicist Stephen Hawking, for example, recently warned that aliens may be more interested in mining our planet for vital resources than in getting to know us.
The prospect of greedy, imperialistic aliens is a troubling one, but Conway Morris thinks another scenario — also depressing — is more likely to be true. We're likely alone in the universe, he writes. The cosmos is almost inconceivably vast, likely harboring at least billion galaxies. And our solar system is relatively young compared to the rest of the universe — 4. The ultimate success of SETI also depends upon the average longevity of technologies assuming there are others out there besides ourselves.
Longevity or "L" is the last term in the Drake Equation , a formula designed to estimate the number of communicative civilizations in our galaxy. In fact, the length of time a technologically advanced species might continue to transmit is completely unknown and unknowable until, or unless, contact is made. I think that Prof. Hawking made the point that a short-lived technological society a small value for "L" means little chance of contact.
But it L is large, it is likely that SETI searches will succeed and that the civilization that's transmitting is using a technology that is older and more advanced than our own. Of course he's right, but there's a lot of room for different opinions about what contact with an advanced technology would mean. In describing the search for extraterrestrial intelligence, Prof. In that case, we are talking about contact through electromagnetic communication. What about physical contact? Well, one thing is for sure: If they can get here, then their technology is superior to ours, and not just by a little!
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