Monday, 26 December 2011
First Habitable Exoplanet Found – Once Again?
Images courtesy of NASA/Ames/JPL-Caltech.
During the past few years, exoplanets have repeatedly made headlines. However, when the initial buzz was over, the discoveries turned out to be much ado about planets that could not even in theory support life as we know it. As planets are found through indirect methods, some of them might not actually exist at all and most have been too hot worlds.
Recently, NASA announced that it had found the first exoplanet orbiting in the habitable zone of its sun. With a radius of 2.4 times that of the Earth, Kepler 22b orbits a sun similar to ours.
However, a habitable zone is a flexible concept. In our solar system, Venus and Mars are in the habitable zone but do not look habitable at all. Much more is needed, such as the presence of liquid water and a good-sized moon without which life in the Earth’s oceans would die out.
Once again, the latest discovery is probably a false positive.
NASA's Kepler Mission Confirms Its First Planet in Habitable Zone of Sun-like Star. NASA (5 December 2011).