Previous observations suggested that Ceres was less than 30% ice, and its craters were thought to imply that the dwarf planet ...

Watch this video to find out more about the Earth, planets in our Solar System and other planets far off in outer space. From up here on the International Space Station I get a great view of Earth.

Narrator: As the solar system grew, four rocky planets: Mercury, Venus, Earth and Mars, were created closest to the Sun. Made of rocks and metals, they have solid surfaces and a central core of ...