what was the last time someone walked on the moon
December 12, 1972
Apollo 17
On December 12, awakened by "Ride of the Valkyries", Cernan and Schmitt began their second lunar excursion. 
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Apollo 17 [SEP] Lunar surface
The crew deployed the ALSEP just west of the landing site. This task done, they departed for the first geological survey station: Steno crater to the south of the landing site. The astronauts gathered of samples, took seven gravimeter measurements, and deployed two explosive packages. The latter were detonated remotely to test geophones placed by the astronauts, and also seismometers left during previous missions. The EVA ended after seven hours and twelve minutes. On December 12, awakened by "Ride of the Valkyries", Cernan and Schmitt began their second lunar excursion. First, the rover's fender needed a better fix. Overnight, the flight controllers devised a procedure communicated by John Young: taping four cronopaque maps together and clamping the "replacement fender extension" onto the fender.