A shell of icy objects at the edge of the solar system known as the Oort cloud has a pair of spiral arms that resemble a miniature galaxy, new research suggests.

A rare full seven-planet alignment will be visible in the early night sky between Feb. 22 and 28. We have the tips you need ...

The mysterious Oort cloud is the source of many of our solar system's comets, but astronomers still have no idea what it ...

What if Earth had massive rings like Saturn? Our skies would never look the same, with stunning celestial views stretching ...