It's Carl Sagan's birthday! Time to party like the starstuff that we are.

Happy birthday, Carl Sagan! The legendary astronomer, astrophysicist, cosmologist and science educator would have been 78 today. To celebrate, we've rounded up a handful of our favorite Sagan posts and curated some stellar content from other websites that are honoring him today. Feel free to contribute in the comments! »11/09/12 5:14pm11/09/12 5:14pm