spacetoday.net: Extrasolar "waterworld" discovered

Posted: Thu, Dec 17, 2009, 6:21 AM ET (1121 GMT)
GJ1214 exoplanet illustration (CfA)

Astronomers announced Wednesday the discovery of a super-Earth exoplanet that they believe is a watery, if inhospitable, world. Researchers reporting in the latest issue of the journal Nature announced the discovery of the planet orbiting GJ1214, a red dwarf star 40 light-years away. The planet is about 6.5 times the mass of the Earth and orbits the star every 38 hours, creating a surface temperature of 400 degrees Fahrenheit. Astronomers believe that the planet is likely surrounded by a dense atmosphere with a rocky, perhaps molten surface, but with an interior of water ice. Astronomers detected the planet using an array of small telescopes, similar to what's commercially available for amateur astronomers, that detected the change in brightness of the star as the planet transited in front of it as seen from the Earth.