Europa : Moon of Jupiter - The sixth-closest moon of Jupiter and the smallest of the four Galilean moons, but it is still the sixth-largest moon in the Solar System. It is primarily made of silicate rock and has a water-ice crust. The core is probably iron-nickel. Europa is slightly smaller than the Moon (Luna)
Astronomers have discovered a rocky planet that weighs 17 times as much as Earth and is more than twice as large in size. This discovery has planet formation theorists challenged to explain how such a world could have formed.
ageofdestruction: spindrift: Dione, moon of Saturn, photographed by Cassini, 3rd February 2007. 7 frames, each a composite of a red, a green, and a violet image. Image credit: NASA/JPL/SSI. Animation: AgeOfDestruction.
An artist has created in a stunning circular image of the entire observable universe using NASA images based on astronomical surveys provided by Princeton University. It’s also quintessentially geocentric – with Earth’s solar system right at the center.
BPM 37093 ("Lucy"). The inside of white dwarf stars often is pure carbon and the extreme pressure in this one has turned it into diamond. (Credit: Harvard-Smithsonian Center for Astrophysics / Travis Metcalfe, Ruth Bazinet) Mona Evans, "Centaurus the Centaur" http://www.bellaonline.com/articles/art181491.asp