Harrison Schmitt cancelled in September 1970, the community of lunar geologists supporting Apollo felt so strongly about the need to land a professional geologist on the Moon, that they pressured NASA to reassign Schmitt to a remaining flight. As a result, Schmitt was assigned in August 1971 to fly on the last mission, Apollo 17, replacing Joe Engle as Lunar Module Pilot. Schmitt landed on the Moon with commander Gene Cernan in December 1972. Schmitt claims to have taken the photograph of the Earth known as "The Blue Marble", possibly one of the most widely distributed photographic images in existence. NASA officially
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