Six of our cosmic neighbors are expected to line up across the night sky tonight, in what has been dubbed a "planetary parade ...

Alignments of five or more planets are rare—there will be two more featuring five or more planets this year, but after that ...

Plus: Saturn’s moon Iapetus is visible, our Moon passes the bright star Spica, and Mars skims south of Pollux in Gemini in ...

A tiny asteroid loitering in a near-Earth orbit for a few months last year may have an intriguing origin on our moon. Its ...