Quote from Wikipedia: "Gliese 581d is an extrasolar planet orbiting the star Gliese 581 approximately 20 light-years away in the constellation of Libra. Because of its mass, between 7 and 14 times that of Earth, the planet is classified as a super-Earth. In late April 2009, new observations by the original discovery team concluded that the planet is within the habitable zone where liquid water may exist".
My depiction of the surface of Gliese 581d and possible moons.
Done with Terragen 2 and Photoshop.
Sizes in download:
Edit 7/19/10: After reading Siamon89's comment I brightened it a bit. I also added a 1920X1080 which wasn't in the original download.