You can probably imagine an early universe without planets or stars — but what did the universe look like before time existed? This fall, you could find out by taking a free class led by prominent ...

Get to know host Phil Plait and begin with answering a simple question: what is astronomy? Welcome to the first episode of Crash Course Astronomy. Your host for this intergalactic adventure is the Bad ...

Astronomy professor Chris Impey's MOOC, or Massive Online Open Course, has already signed up more than 1,000 students and it recently got a shout-out from Sports Illustrated, which listed "free online ...