The first “J mission” — science over speed

Apollo 15 was the first of the Apollo program’s three extended “J missions” — a longer stay on the Moon, more science, and for the first time a lunar rover. It was commanded by David Scott, a veteran of Gemini 8 and Apollo 9, alongside Alfred Worden and James Irwin, for both of whom it was their only spaceflight.

The ship launched on 26 July 1971 at 13:34 UTC from Pad 39A on a Saturn V that had been struck by lightning at least four times during preparations without damage. Shortly after launch a fault light appeared for the SPS propulsion system — suspecting a real malfunction, the crew decided to use the affected circuit only manually and only for major burns.

The crew named the modules Endeavour (command module, after James Cook’s ship) and Falcon (lunar module, after the mascot of the US Air Force Academy, which all three astronauts had attended). Pilot Worden handled docking the modules and jettisoning the spent S-IVB stage, which struck the Moon an hour later and set off the seismometers left by Apollo 12 and 14.