Jupiter's four Galilean moons will line up in front of Jupiter in the early morning sky on Aug. 8. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works ...

James is a published author with multiple pop-history and science books to his name. He specializes in history, space, strange science, and anything out of the ordinary.View full profile James is a ...

Add Yahoo as a preferred source to see more of our stories on Google. On January 7, 1610, the Italian astronomer Galileo discovered three of Jupiter's moons: Callisto, Europa and Io. When he looked at ...

Sky This Week is brought to you in part by Celestron. Friday, February 6The bright star Sirius dominates the southern sky ...