Countdowns

Here are some of the more prominent Mars movies over the decades, to encourage you to keep exploring.

The four Galilean moons of Jupiter are Io, Europa, Callista and Ganymede.

Almost 100 missions have been sent to the moon. Here are some of the best.

Nine exceptionally bright "Great Comets" have been visible to the naked eye over the past 300+ years.

See amazing photos of those dirty snowballs in space: comets.

In honor of the 40th anniversary of "Star Wars: A New Hope," here are 40 surprising facts about the movie that started it all.

What do you want to know about the supermoon?

Humans have sent many missions, both manned and robotic, beyond our planet to explore our neighboring celestial bodies.

Apollo 13 was NASA's third moon-landing mission, but the astronauts never made it to the lunar surface. Here are the events that transpired.