Exclusive: “Most Earth-Like” Exoplanet Gets Major Demotion—It Isn’t Habitable
Last month, when astronomers with the Kepler space telescope released a list of 1,235 possible planets orbiting other stars, one particular candidate, KOI 326.01, especially stood out. Scientists, journalists, and the general public couldn’t help it: In a population of planetary candidates dominated by sizzling, Jupiter-sized gas giants—which are much easier to spot—here was the closest thing yet to our very own planet. It was just about the size of Earth, even a little smaller, and had a temperature around 138 degrees—rather warm for human tastes, but still a place where liquid water could rain down from clouds into oceans, and where life as we know it could possibly exist. A clever but perhaps overambitious monetary calculation valued the planet at exactly $223,099.93.
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The road to demotion began when a DISCOVER fact-checker, Mara Grunbaum, asked for some additional information about the planet. In response, Batalha and her colleagues dug up images of the sky near KOI 326.01—and almost immediately found a problem. The planet’s sun, known as KIC 9880467, is located close to another star (see above). In a reference catalog characterizing the stars in the probe’s field of view, KIC 9880467 is listed as brighter than its neighbor. But as you can easily see in the above image, that is not the case.
http://blogs.discovermagazine.com/80beats/2011/03/08/exclusive-most-earth-like-exoplanet-gets-major-demotion%E2%80%94it-isnt-habitable/