Picture of Apollo 15 lunar roving vehicle Courtesy of the NASA

Apollo 15 marked the start of a new series of missions from the Apollo space program, each capable of exploring more lunar terrain than ever before. Launched on July 26, 1971, Apollo 15 reached the Moon four days later and Astronauts David Scott and James Irwin descended to its surface while Alfred Worden remained in orbit.

After a safe landing in Hadley Rille, the astronauts proceeded to unload NASA's first Lunar Roving Vehicle. The LRV was an ultra-light, electricity-powered dune buggy which could travel at a speed of 6 to 8 miles per hour, much faster than the walking pace of an astronaut on the Moon. Its success in the Apollo 15 mission led to its use in the sixteenth and seventeenth Apollo voyages. Scott and Irwin used the LRV to cover over 17 miles of lunar terrain and collect large amounts of rock samples which the Rover would transport for them.

After performing three space walks and spending nearly three days on the Moon, Scott and Irwin joined Worden in lunar orbit and returned to Earth. Among the 169 lbs of material brought back from the Moon was the famous "Genesis Rock", a piece of old lunar crust studied extensively by scientists for clues to the Moon's geologic history.