Are we alone? Are there other planets like ours? Does life exist elsewhere in the universe? On the 21st anniversary of the discovery of the first planet orbiting another sun-like star, we’re entering a fascinating era where we’re beginning to answer those tantalizing questions that people have pondered for thousands of years. See how: http://nasa.tumblr.com/post/152256737554/a-space-odyssey-21-years-of-searching-for-another
