Astrogeology Science Center

The moon's Mare Tranquillitatis is an ancient plain of volcanic rock pocked with craters and coated with fine dust. In the 1960s, engineers and scientists in the U.S. Geological Survey's Astrogeology Branch reproduced a 10-acre swatch of Mare Tranquillitatis in Cinder Lake, a volcanic cinder field northeast of Flagstaff, Arizona, for use in Apollo astronaut training and lunar vehicle and equipment testing.This video shows how they marked out crater locations, planted explosives, and set them off in three waves, excavating hundreds of craters up to 10 meters wide.