NASA History: Apollo 15 Commander Dave Scott Tests Galileo’s Theory 44 Years Ago
By NASA // August 2, 2015
ABOVE VIDEO: At the end of the last Apollo 15 moon walk, Commander David Scott held out a geologic hammer and a feather and dropped them at the same time. Because they were essentially in a vacuum, there was no air resistance and the feather fell at the same rate as the hammer, as Galileo had concluded hundreds of years before. (NASA.gov Video)
NASA – On August 2, 1971, during their last moonwalk, Apollo 15 Commander Dave Scott performed a live demonstration to test Galileo’s theory that in a vacuum all objects fall at the same rate regardless of their mass.
On Earth, given two objects of different mass, the lighter object will often fall more slowly because of air resistance.
However, on the Moon, which is essentially a vacuum, two objects of different masses should fall at the same rate.
As thousands watched from Earth via live television coverage, Scott dropped a geologic hammer and a feather simultaneously.