CAPE CANAVERAL, Fla. -- Space shuttle Discovery heads to space after lifting off from Launch Pad 39A at NASA's Kennedy Space Center in Florida to begin its final flight to the International Space Station on the STS-133 mission. Launch was at 4:53 p.m. EST on February 24, 2011. The six-member crew delivered the Permanent Multipurpose Module, packed with supplies and critical spare parts, as well as Robonaut 2, the dexterous humanoid astronaut helper, to the orbiting outpost. Discovery flew its 39th and final mission and was retired following STS-133. This is the 133rd Space Shuttle Program mission and the 35th shuttle voyage to the space station.  Photo credit: NASA/Kenny Allen and Mike Gayle