Discovery blaze a trail of smoke and steam as it heads toward orbit on the STS-133 mission to the International Space Station.

In Firing Room 4 of the Launch Control Center at NASA's Kennedy Space Center in Florida, Shuttle Launch Director Mike Leinbach watches space shuttle Discovery blaze a trail of smoke and steam as it heads toward orbit on the STS-133 mission to the International Space Station.

Discovery and its six-member crew are on a mission to deliver 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 is making its 39th mission and is scheduled to be retired following STS-133. This is the 133rd Space Shuttle Program mission and the 35th shuttle voyage to the space station. For more information on the STS-133 mission, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Kim Shiflett