Harrison Hagan Schmitt (born July 3, 1935) is an American geologist, retired NASA astronaut, university professor, former U.S. senator from New Mexico, and the most recent living person—and only person without a background in military aviation—to have walked on the Moon. "Perhaps the hardest thing to get used to on the Moon is that the sky is completely black. There's no blue at all." In December 1972, as one of the crew on board Apollo 17, Schmitt became the first member of NASA's first scientist-astronaut group to fly in space. As Apollo 17 was the last of the Apollo missions, he also became the twelfth and second-youngest person to set foot on the Moon and the second-to-last person to step off of the Moon (he boarded the Lunar Module shortly before commander Eugene Cernan). Schmitt also remains the only professional scientist to have flown beyond low Earth orbit and to have visited the Moon. He was influential within the community of geologists supporting the Apollo program and, before starting his own preparations for an Apollo mission, had been one of the scientists training those Apollo astronauts chosen to visit the lunar surface. Schmitt resigned from NASA in August 1975 to run for election to the United States Senate as a member from New Mexico. As the Republican candidate in the 1976 election, he defeated Democratic incumbent Joseph Montoya. In the 1982 election, Schmitt was defeated by Democrat Jeff Bingaman. Born July 3, 1935, in Santa Rita, New Mexico, Schmitt grew up in nearby Silver City, and is a graduate of the Western High School (class of 1953). He received a B.S. degree in geology from the California Institute of Technology in 1957 and then spent a year studying geology at the University of Oslo in Norway, as a Fulbright Scholar. He received a Ph.D. in geology from Harvard University in 1964, based on his geological field studies in Norway. Before joining NASA as a member of the first group of scientist-astronauts in June 1965, he worked at the U.S.