Fifteen years ago Monday, at 12:38 p.m. Pacific Time, astronaut Steven Hawley directed the space shuttle's robotic arm to release the Hubble Space Telescope 381 miles above the Earth, launching an era of unprecedented scientific discoveries.
http://wired.com/news/space/0,2697,67304,00.html?tw=wn_tophead_1

Some cool pictures after the Jump: