AS15-92-12424 (31 July-2 Aug. 1971) --- Astronaut James B. Irwin, lunar module pilot, uses a scoop in making a trench in the lunar soil during Apollo 15 extravehicular activity (EVA) on the moon. Mount Hadley, which rises approximately 14,765 feet (about 4,500 meters) above the plain, is in the background. Its base is 14 kilometers (about 8.4 miles) away. The gnomon is at left. While astronauts Irwin, and David R. Scott, commander, descended in the Lunar Module (LM) to explore the moon, astronaut Alfred M. Worden, command module pilot, remained with the Command and Service Module (CSM) in lunar orbit.