Apollo 15 was the ninth crewed Apollo mission and the fourth to land on the Moon. Launched on July 26, 1971, it marked a turning point in lunar exploration as the first “J mission” — an extended scientific expedition designed for longer stays, greater mobility, and deeper investigation of the lunar surface. The crew consisted of Commander David Scott, Command Module Pilot Alfred Worden, and Lunar Module Pilot James Irwin.

The mission targeted the Hadley-Apennine region, one of the most geologically dramatic landing sites of the Apollo program. Nestled at the base of the Apennine Mountains and along the edge of Hadley Rille — a sinuous channel over a mile wide — the site promised extraordinary scientific returns. Apollo 15 debuted the Lunar Roving Vehicle (LRV), giving astronauts the ability to travel far beyond walking distance for the first time. Scott and Irwin drove the rover 17.3 miles across the lunar surface over three EVAs totaling 18 hours and 33 minutes, collecting 170 pounds of samples.

Among the mission’s most celebrated moments was the discovery of the “Genesis Rock” (sample 15415), a 4-billion-year-old anorthosite believed to be a piece of the Moon’s original crust. Scott also performed Galileo’s famous experiment on live television, dropping a hammer and a falcon feather simultaneously to demonstrate that objects fall at the same rate in a vacuum. During the return trip, Alfred Worden conducted one of the most remote spacewalks in history, retrieving film cassettes from the Scientific Instrument Module bay during a deep-space EVA.

Apollo 15 also deployed the first lunar subsatellite, left in orbit to study the Moon’s gravity field and plasma environment. The crew splashed down in the North Pacific on August 7, 1971, and was recovered by the USS Okinawa. The mission fundamentally expanded the scope of what could be achieved on the lunar surface and set the template for the final two Apollo landings.