Because there are only so many body and facial types, most people are bound to have a look-a-like whom they have never met. Who hasn't imagined what it would be like to stumble upon a "twin" in some obscure corner of the planet?
Because the universe is infinitely larger than Earth, the chances of spotting a planet that looks like ours circling a star that is similar to ours is now pretty good, thanks to the phenomenal performance of NASA's Kepler space telescope.
Last week at the American Astronomical Society's meeting in Long Beach, Calif., the buzz was about the telescope's discovery of what may be the most Earth-like planet ever detected beyond the solar system. Inelegantly dubbed KOI 172.02, this "Super-Earth" is only slightly bigger than our own and is believed to have a rocky surface. It is also a comfortable distance from its sun in what scientists call the "habitable zone." KOI 172.02 may harbor life as we understand it, if it also has water.
NASA has not released information about the star that KOI 172.02 orbits or how many light-years it is from Earth, but that information should be coming soon. It isn't as if any rival nation on Earth is in a position to plant a flag on it anytime soon.
To say scientists are excited about finding KOI 172.02 is an understatement. The consensus is that there may be as many as 17 billion Earth-size planets in the Milky Way galaxy alone, but no one knows yet how many of them are Earth-like.
Thanks to Kepler, humans now know of at least one other planet that might be able to accommodate aliens. Now, if only science could figure out how to bridge the distance between Earth and its twin.