Jack Schmitt joined the Astrogeology team as a geologist at the Flagstaff Science Center in 1964, having recently earned a doctorate degree from Harvard University. In addition to assisting in the geologic mapping of the Moon, he led the Lunar Field Geological Methods project. When NASA announced a special recruitment for scientist-astronauts in late 1964, Schmitt applied. Out of more than 1,000 applicants, six were chosen. Of those six, Joe Kerwin, Owen Garriott, and Edward Gibson would fly in the Skylab missions in 1973 and 1974, and Schmitt would go to the Moon on the Apollo 17 mission.
Just one year after joining the USGS, Schmitt was transferred to NASA and began his pilot training at Williams Air Force Base in Arizona. On December 7, 1972, Apollo 17 was launched, carrying Schmitt, Ronald Evans, and mission commander Eugene Cernan. On December 11, the lunar module, Challenger, landed at Taurus-Littrow on the Moon, and four hours later Cernan and Schmitt became the eleventh and twelfth men to walk on the moon. The pair did a total of three EVAs (extravehicular activities) before their departure on December 14, collecting rock and soil samples, taking photographs, setting up equipment, and making observations. During the mission, Schmitt and Cernan discovered orange soil, an surprising find that created a great deal of excitement in the scientific community. Schmitt was the only geologist to go to the Moon.
Apollo 17 was the final manned mission in a four year exploration of the Moon. The crew of Apollo 17 left a plaque that reads:
"Here man completed his first exploration of the Moon, December 1972 A.D. May the spirit of peace in which we came be reflected in the lives of all mankind."