Astronauts Shepard and Mitchell practice using Active Seismic Experiment

S71-15273 (October 1970) --- Apollo 14 astronauts Alan B. Shepard Jr., commander (right); and Edgar D. Mitchell, lunar module pilot, practice using the Active Seismic Experiment (ASE) to set off explosions on the lunar surface and arm a mortar to launch four grenades after they leave. Measurements of the ensuing vibrations of the moon, radioed to Earth, will give scientists new information on the shape, structure and thickness of the outer lunar crust. ASE will be deployed during one of two Apollo 14 extravehicular activity (EVA) periods.