The high vantage point allowed astronauts to take photographs of celestial objects in spectral bands not seen from Earth.
Photo:NASA
The grenade throwing was part of a more serious endeavor called the Active Seismic Experiment.
Any seismic activity generated by quakes and explosions produces a bunch of different waves.
Some of these waves can travel through solid rock, but not through liquid.
Because the moon is seismically very quiet it was necessary to generate artificial moonquakes.
Thats where the grenades come in.
The mortar produced stronger waves that allowed scientist to look deeper into the lunar crust.
A series of geophones laid out in a line detected the seismic waves generated.
The mortar package for Apollo 16’s Active Seismic Experiment.
The failure of the rest were attributed to accumulation of dirt on the firing switch actuator bearing surface.
The mortars were not fired because it was determined that firing them would have caused damage to other equipment.
These grenades still remain unfired on the moon.
Each contain between 45 to 450 grams of hexanitrostilbene, a heat-resistant high explosive.
By Apollo 16, the NASA had readied an improved mortar.
This time they were fired up to a distance of 900 meters.
It too remains on the moon.
Of the 22 thumper charges, 19 were successfully fired.
Buzz Aldrin deploys a seismometer in the Sea of Tranquillity.
