Planetary alignments aren't rare, but they can be when they involve six of the eight planets in our solar system.

For a few months, Earth had a second moon — a tiny asteroid that may have been a piece of our own Moon ...

What if Earth had rings like Saturn? This fascinating thought experiment explores how massive planetary rings would change ...

The Moon passes 0.3° south of the bright red giant star Antares at 7 P.M. EST. However, the pair isn't visible this evening, as they'll rise in the early-morning sky, so we'll feature them tomorrow.