(“Apollo 15” was the 9th manned mission in the United States’ ‘Apollo’ program, the 4th to land on the ‘Moon’, and the 8th successful ‘manned mission’)
(it was the first of what were termed “J missions”, long stays on ‘the moon’, with a greater focus on ‘science’ than had been possible on previous ‘missions’)
(it was also the first mission on which the “Lunar Roving Vehicle” was used)
(the mission began on “26 july 1971”, and ended on “August 7”)
(at the time, NASA called it the “most successful manned flight ever achieved”)
(commander “David Scott” and Lunar Module Pilot “James Irwin” spent 3 days on the ‘Moon’, including 18½ hours outside the spacecraft on “lunar extra-vehicular activity (aka “EVA”))
(the mission landed near “hadley rille”, in an area of the “Mare Imbrium” called Palus Putredinus (‘Marsh of Decay”)
(the crew explored the area using the first ‘lunar rover’, which allowed them to travel much farther from the “Lunar Module” (LM) than had been possible on missions without the rover)
(they collected 77 kilograms (170 lb) of “lunar surface material”)
(at the same time, “Command Module Pilot Alfred Worden” orbited ‘the moon’, using a “Scientific Instrument Module” (SIM) in the “Service Module (SM) to study the lunar surface and environment in great detail with a ‘panoramic camera’, ‘a gamma-ray spectrometer’, a ‘mapping camera’, a laser altimeter, a mass spectrometer, and a lunar sub-satellite deployed at the end of Apollo 15’s stay in lunar orbit (an “apollo program first”))
(the mission successfully accomplished its objectives, but was marred by negative publicity that accompanied disclosure of the crew carrying unauthorized “postage stamps” which they had planned to sell after their return)
(ironically, this mission was one of very few that had been honored with the issue of a commemorative US stamp, with this first use of a ‘lunar rover’ happening one decade after the first “mercury” astronaut launch)