http://www.jpl.nasa.gov/news/news.cfm?release=2011-373&cid=release_2011-373
What makes Earth so special? Our planet harbors everything necessary for life, which is an extraordinary coincidence. We have liquid water, oxygen, and enough sunlight that we are neither too hot nor too cold. These criteria for any life at all, not to mention intelligent life, are so specific that we have never confirmed them anywhere else in the known universe. We are lucky to exist in something called the habitable zone, an area of orbit around a sun that can produce life in planets. We could not comfortably live in any planet out of the habitable zone without respirators, pressurized suits, specialized buildings and vehicles, etc.
As you can see, a habitable zone occupied by a solid planet is exceedingly rare. Most solar system's zones are far beyond their farthest planet, or so close to the star that the planets are frigid. As a species, our space programs allow us to shout into the void, calling out for reassurance that we aren't the only intelligent life in the universe. Even physicist Steven Hawking says it would be foolish to think we are alone in such a gargantuan space. NASA's Kepler mission, an attempt to find the habitable zone in other systems, has provided intriguing results. Kepler has found several hundred candidates that MAY be in the habitable zone, and one looks especially promising. The planet, christened Kepler-22b, is near earth size, and orbits in the zone where liquid water may well exist. 22b is slightly larger than earth, but its 290 day year is not so much different from ours. It is 600 light-years away, making travel there currently impossible, but we will continue to study it from our place in the universe. Who knows? Maybe we're being studied back.
I'm not entirely sure the idea of someone studying humans is more scary or amusing.
ReplyDeletecan you imagine people from another planet far away looking into a telescope at someone playing, for example, angry birds. "I'll never understand these beings obsession with small devices that appear to show birds committing suicide." the thought makes me laugh.
cosmically, we're probably pretty low on the pecking order. Steven Hawking predicts the first meeting between humans and extraterrestrials to be like Cortez meeting the Aztec. We all know how that turned out.
ReplyDeleteReally interesting stuff, i never knew that there was a habitable zone, i just thought it was planet specific. If that makes sense. It would be crazy to think that these isn't life on other planets in the universe, after all, it is constantly expanding.
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