Mars and Martians have inspired science fiction forever. The debate about life on Mars started again with the discovery of fossilized life-forms in a meteorite from the planet.

65 million years ago, an object just ten kilometers across wiped out all of Earths dinosaurs. Could humanity survive an impact of that magnitude?

Our view outside of the Milky Way is shrouded by a fog of cosmic dust. Using radio telescopes, astronomers can now penetrate interstellar clouds and see beyond our galaxy.

Its the smallest, coldest, weirdest, most distant planet from Earth and the only planet never visited by a space mission. NASA has provisional plans for a mission there.

Andromeda looks like a typical spiral galaxy, but astronomers suspect that our galactic neighbor has two hearts" and possibly a gigantic black hole at its core.

Orion is a favorite target of backyard astronomers. At Orions heart lies a colossal hydrogen cloud, believed to be the place where new stars are born.