Last Updated: Wednesday, January 30, 2013, 16:46
The habitable zone defines the region where a planet might be able to retain liquid water on its surface.
Last Updated: Wednesday, January 9, 2013, 09:04
Researchers have discovered 15 new planet candidates orbiting in the habitable zones of other stars.
Last Updated: Tuesday, September 13, 2011, 09:17
Astronomers believe they have found a second planet outside our solar system that seems to be in the right zone for life, just barely.
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