Harrison Schmitt credits the image to the entire Apollo 17 crew. While on the Moon's surface, Schmitt — the only geologist in the astronaut corps — collected the rock sample designated Troctolite 76535, which has been called "without doubt the most interesting sample returned from the Moon". Among other distinctions, it is the central piece of evidence suggesting that the Moon once possessed an active magnetic field. As he returned to the Lunar Module before Cernan, Schmitt is the next-to-last person to have walked on the Moon's surface. After the completion of Apollo 17, Schmitt played an active role in documenting the
Curt Michel NASA scientist-astronaut in June 1965. He resigned from NASA in September 1969 without having being assigned to any spaceflight missions. Michel believed that it was his decision to resign, after it became clear that he would not be given a flight assignment, that motivated the scientific community to demand that his fellow scientist-astronaut Harrison Schmitt be reassigned to Apollo 17 after Schmitt's planned mission on Apollo 18 was cancelled. After his resignation from NASA, Michel returned to teaching and research at Rice, where he also served as chair of the space physics and astronomy department from 1974 to 1979. He