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
Tsiolkovskiy (crater) in Mendeleev crater far to the northeast are called Catena Mendeleev, and the row points directly at Tsiolkovsky. For this reason the craters are believed to be secondaries from the Tsiolkovsky impact. This feature was discovered on photographs sent back by the Russian spacecraft Luna 3, and was subsequently imaged by several of the American Lunar Orbiters and then by Apollo astronauts. Apollo 17 Astronaut Harrison "Jack" Schmitt and other scientists (Schmitt was the only trained scientist, a geologist, to walk on the moon) strongly advocated Tsiolkovskiy as the landing site of Apollo 17, using small communications satellites deployed from