Commander John Young leaps up from the lunar surface to salute the U.S. flag during the first Apollo 16 extravehicular activity. The Lunar Module and Rover are on the left and Stone Mountain is in the background. Young and Charles Duke spent 20 hours exploring the surface of the moon after their lunar landing on the Plain of Descartes on April 20, 1972. They collected 213 lbs. of lunar material and performed geophysical studies using a magnetometer and seismometer. NASA Photo 10075832