Apollo 17

Apollo 17: launchApollo 17 lifting off from Kennedy Space Center, Florida, atop a Saturn V three-stage rocket, December 7, 1972.

Apollo 17, U.S. crewed spaceflight to the Moon, launched on December 7, 1972, and successfully concluded on December 19, 1972. It was the final flight of the Apollo program, and Apollo 17 astronauts Eugene Cernan and Harrison Schmitt were the last humans to walk on the Moon.

Cernan, the mission commander, was a seasoned astronaut, who had orbited Earth on Gemini 9 and the Moon (without landing there) on Apollo 10. Schmitt, the lunar module pilot, held a Ph.D. in geology and was the first scientist-astronaut to set foot on the Moon. The third crew member was Ronald Evans, the command module pilot. Like Cernan, he had been a naval aviator before becoming an astronaut.

The Apollo 17 mission was the first nighttime Apollo launch. Liftoff from Kennedy Space Center in Florida had been scheduled for the evening of December 6, 1972, but a technical malfunction resulted in a delay until 12:33 am the following day. The three-stage Saturn V rocket-powered launch vehicle took less than 12 minutes to reach Earth orbit. A few hours later, the command and service module (the spacecraft that would take the astronauts into lunar orbit), separated from the launch vehicle and docked with the lunar module. The last remaining stage of the launch vehicle was then released and set on a course to crash into the Moon. The astronauts’ spacecraft reached lunar orbit on December 10.

Cernan and Schmitt landed the lunar module, named Challenger, on the surface of the Moon on December 11, 2 hours and 34 minutes after separation from the command and service module. They landed in the Taurus-Littrow Valley, a region chosen by mission planners for its geologic interest, notably the proximity of “young” (less than 3-billion-year-old) volcanic areas. A few hours after landing, Cernan stepped out of the lunar module for the first of three periods of extra-vehicular activity (EVA). There were more than 22 hours of EVA in all, during which Cernan and Schmitt traveled 19 miles (30.5 km) in their lunar rover, an electrically powered wheeled vehicle of a type first used in the Apollo 15 mission. They gathered 243.65 pounds (110.52 kg) of rock and soil samples; performed experiments pertaining to lunar gravity, seismic activity, and other subjects; and deployed an “experiment package” that transmitted data back to Earth for several years. Meanwhile, Evans orbited the Moon in the command and service module.

After 75 hours on the surface, Cernan and Schmitt lifted off on December 14 and rejoined Evans a little more than two hours later. Once the astronauts’ equipment and scientific specimens had been unloaded, the lunar module was no longer needed and was therefore allowed to drop to the lunar surface. On December 16 the command and service module left lunar orbit, and the astronauts set course for Earth. On the following day Evans performed several spacewalks to collect photographic equipment from the service module. After this was done, the service module, which had been used mostly for storage and propulsion, was detached from the command module. On December 19 the command module, named America, splashed down in the South Pacific Ocean, only 4 miles (6.5 km) from the recovery ship USS Ticonderoga. America was later put on display at Space Center Houston, the visitor center of the National Aeronautics and Space Administration’s Johnson Space Center.

It was known at the time of Apollo 17 that there would be no more crewed Moon landings for years to come. As he took his last steps on the surface, Cernan made a short speech that ended with a vow that “we shall return, with peace and hope for all mankind. Godspeed the crew of Apollo 17.”

Robert Lewis