Apollo 17: The Beginning of the End of Humans on the Moon

This is how the crescent Earth rise looked to the Apollo 17 crew when they were just above the moon's surface. (AP Photo/NASA)

Apollo 17 astronauts Harrison Schmitt (second from left) and Eugene Cernan (second from right) press their hands in the wet concrete at Adler Planetarium in Chicago on Nov. 13. Their handprints and footprints, as well as those of Apollo 13 astronaut James Lovell, will be displayed in an upcoming exhibit to celebrate the 40th anniversary of the Apollo 17 mission. (AP Photo/Kiichiro Sato)

In the white room high above Launch Complex 39A, Ronald E. Evans prepares to join Cernan and Schmitt in the spacecraft, partially shown in rear. (NASA)

An Oct. 11, 1972 photo of Schmitt. (AP photo/Jim Kerlin)

Apollo 17 Command Module Pilot Ronald E. Evans says goodbye to his wife, Jan, as he and astronauts Eugene Cernan (right) and Harrison Schmitt (in rear) leave the Manned Spacecraft Operations Building in route to the launch pad. In the background is astronaut Alan Shepard greeting Barbara Cernan, wife of the mission commander. (NASA)

The 363-foot tall Apollo 17 space vehicle is launched from the Kennedy Space Center at 12:33 a.m. (EST), Dec. 7, 1972. Apollo 17, the final lunar landing mission in NASA's Apollo program, was the first nighttime liftoff of the Saturn V launch vehicle. A two-hour-and-40-minute hold delayed the launching. (NASA)

Scientist-astronaut Schmitt is photographed standing next to a huge, split lunar boulder during the third Apollo 17 extravehicular activity at the landing site. The mosaic was photographed by Cernan. (NASA/Eugene Cernan)

Altogether, Cernan and Schmitt spent about 75 hours on the moon in the Taurus-Littrow valley, while Evans orbited overhead. (Apollo 17, NASA)

Near the beginning of their third and final excursion across the lunar surface, Schmitt took this picture of Cernan flanked by an American flag and their lunar rover's umbrella-shaped high-gain antenna. The Sculptured Hills lie in the background while Schmitt's reflection can just be made out in Cernan's visor. (Apollo 17, NASA)

Near the Apollo 17 landing site, Family Mountain (center background) and the edge of South Massif (left) frame the lunarscape in this photo of astronaut Harrison Schmitt working alongside the lunar rover. (Apollo 17, NASA)

Carnan makes a short checkout of the Lunar Roving Vehicle during the early part of the Apollo 17 extravehicular activity at the Taurtus-Littrow landing site. (AP/NASA PHOTO)

The Apollo 17 command module America makes a perfect splashdown in the Pacific south of Pago Pago on Dec. 19, 1972, at the end of the final lunar mission of the Apollo series. (AP Photo/PL)

Evans's family watches the successful touchdown in their home near the Manned Spacecraft Center in Houston on Dec. 19, 1972. (AP Photo)

This August 2011 image made available by NASA shows paths left by walking astronauts (single lines) and lunar buggy tracks (parallel lines) from the 1972 Apollo 17 moon mission. NASA's Lunar Reconnaissance Orbiter made this and other photographs of lunar landing sites from 13 to 15 miles above the moon's surface. (AP Photo/NASA)

This December 1972 photo released by NASA shows a view of the Earth as seen by the Apollo 17 crew while traveling toward the moon. Only two dozen men, those who traveled to the moon, have had the full Earth view. The image extends from the Mediterranean Sea area (top) to the Antarctica south polar ice cap, made visible for the first time by the Apollo trajectory. (AP Photo/Courtesy of Earth Sciences and Image Analysis Laboratory, NASA Johnson Space Center)