English: S81-30845 (14 April 1981) --- The 122-feet-long (37.2 meters) space shuttle orbiter Columbia approaches its dry lake bed landing site at Edwards Air Force Base in southern California to successfully complete a two-and-one-third day orbital mission. Astronauts John W. Young and Robert L. Crippen are onboard the spacecraft. This low angle view reveals the array of thermal tiles on the underside of the orbiter--part of a thermal system which protects Columbia upon its return trip through Earth's atmosphere. The photo was taken moments before the lowering of the landing gear.