Rather than a cold, featureless ball on the fringes of the solar ... and valleys. Charon, its biggest of five moons, was discovered in 1978 by the U.S. Naval Observatory. At about 750 miles ...

Scientists have long thought that the South Pole-Aitken basin was formed by a shallow-angle impact, but new research suggests ...

NASA's Juno spacecraft has discovered a giant volcanic hot spot on the surface of Jupiter's hellish moon Io. The eruptions in ...

The Indian Space Research Organisation just released a picture of Mars’ closest and biggest moon — Phobos. The image features Phobos’ largest crater, Stickney, along with three smaller craters.