Apollo 15

Apollo 15
NASA Johnson Space Center Restored by Bammesk · Public domain · source
Name	Apollo 15
Mission type	Crewed lunar landing
Operator	NASA
Mission duration	12 days, 7 hours, 11 minutes, 53 seconds
Spacecraft	CSM Endeavour / LM Falcon
Manufacturer	North American Aviation / Grumman
Launch mass	52,759 kg
Launch date	July 26, 1971, 13:34:00.6 UTC
Launch rocket	Saturn V SA-510
Launch site	Kennedy Space Center LC-39A
Landing date	August 7, 1971, 20:45:53 UTC
Landing site	North Pacific Ocean
Recovery ship	USS Okinawa
Crew members	David Scott, Alfred Worden, James Irwin
Crew caption	Left to right: Scott, Worden, Irwin
Previous mission	Apollo 14
Next mission	Apollo 16

Apollo 15 was the ninth crewed mission in the Apollo program and the fourth to land on the Moon. Launched on July 26, 1971, it was the first of the "J-missions," designed for longer stays and greater scientific exploration. The mission featured the first use of the Lunar Roving Vehicle, which allowed astronauts David Scott and James Irwin to extensively explore the Hadley–Apennine region.

Mission overview

The primary objectives were to explore the Hadley Rille and the Apennine Mountains, conduct extensive scientific experiments, and deploy a comprehensive suite of surface instruments. The mission utilized an uprated Saturn V rocket and a more capable Command and Service Module with enhanced scientific instrumentation. Key operational firsts included the deep-space deployment of a Particles and Fields Subsatellite and the use of a rover for far-ranging lunar surface excursions.

Crew and key personnel

The commander was David Scott, a veteran of Gemini 8 and Apollo 9. The Command Module Pilot was Alfred Worden, who operated the CSM Endeavour in lunar orbit. The Lunar Module Pilot was James Irwin, who accompanied Scott to the surface aboard the LM Falcon. The backup crew consisted of Richard Gordon, Vance Brand, and Harrison Schmitt. Flight directors included Glynn Lunney and Gerald Griffin in Mission Control at Johnson Space Center. The mission's success was also supported by teams at the Manned Spacecraft Center and Marshall Space Flight Center.

Mission highlights

After entering lunar orbit, Scott and Irwin landed Falcon near Hadley Rille on July 30. Their three EVAs totaled over 18 hours. Using the Lunar Roving Vehicle, they traversed over 27 kilometers, collecting a diverse geologic sample that included the famous "Genesis Rock," an ancient piece of lunar crust. At the start of the first EVA, Scott performed a televised demonstration of Galileo's theory by dropping a geologic hammer and a falcon feather in the vacuum. In orbit, Worden conducted pioneering observations and operated a suite of cameras, including the SIM bay instruments.

Scientific results

The mission returned 77 kilograms of lunar material, providing critical insights into the Moon's volcanic history and composition. The deployed ALSEP included a Lunar Surface Magnetometer and a Heat Flow Experiment. The Lunar Roving Vehicle carried a ground-penetrating radar. From orbit, Worden's observations and the subsatellite provided extensive data on the Moon's gravitational field and particle environment. Findings contributed to theories about the Imbrium Basin impact and the nature of lunar maria.

Legacy and spacecraft location

Apollo 15 marked a major shift toward rigorous scientific exploration in the Apollo program, setting the standard for the final two J-missions. The mission's success validated the use of the rover and extended lunar operations. The command module Endeavour is on display at the National Museum of the United States Air Force at Wright-Patterson Air Force Base. The lunar module ascent stage was intentionally impacted into the Moon, while the descent stage remains at the Hadley–Apennine landing site. The rover, along with other surface equipment, was also left on the Moon.

Category:Apollo program Category:Human spaceflights to the Moon Category:1971 in spaceflight