Apollo 17

Firsts

First scientist to walk on the Moon.
First Apollo mission launched at night.

Key Dates

Launch: Dec. 7, 1972

Lunar Orbit Insertion: Dec. 10, 1972

Lunar Landing: Dec. 11, 1972

Lunar Surface Departure: Dec. 14, 1972

Recovery on Earth: Dec. 19, 1972

Results

Apollo 17 was the sixth and final mission in the Apollo program that explored the lunar surface, but it was the first in which a scientist got to investigate the Moon firsthand.

Harrison H. Schmitt was a geologist who had been part of the backup crew for Apollo 15. On Apollo 17, he served as pilot of the lunar module, “Challenger.” Eugene A. Cernan was commander and Ronald E. Evans piloted the command module, “America.”

On December 11, 1972, as Evans continued orbiting the Moon, Cernan and Schmitt flew Challenger to a spot on the southeastern rim of Mare Serenitatis (the Sea of Serenity) between massive units of the southwestern Taurus Mountains south of Littrow Crater. Known as the Taurus-Littrow site, it was a flat-floored valley in a broken mountain chain. They touched down within 650 feet (200 meters) of the targeted landing point.

Their two primary objectives were to obtain highland samples older than the impact that created the Imbrium Crater (the area Apollo 15 had explored) and to investigate the possibility of geologically recent, explosive volcanism. They succeeded spectacularly at both.

Rock-Solid Evidence

Among their haul was the oldest known unshocked (unaltered by meteorite impact) rock retrieved from the Moon, a sample called Troctolite 76535, which NASA’s Lunar Sample Compendium calls “without a doubt the most interesting sample returned from the Moon!” It’s believed to be at least 4.2 billion years old, and offers evidence that at one time, the Moon, like Earth, had a magnetic field generated by a dynamo at its core.

Among the haul was the oldest known unshocked (unaltered by meteorite impact) rock retrieved from the Moon, which NASA’s Lunar Sample Compendium calls “without a doubt the most interesting sample returned from the Moon!”
The astronauts met their second goal with Schmitt’s discovery of orange soil near Shorty crater. The color was due to orange and black volcanic glass which had formed in the type of explosive volcanic eruption known on Earth as a “fire fountain.”

They remained on the lunar surface for 75 hours, the longest visit yet. With the help of their rover, they clocked 22 hours of EVA time during which they traveled more than 22 miles (about 36 kilometers), ranging as far as 4.6 miles (7.4 kilometers) from Challenger, just about at the limit of what was considered the walk-back distance in case the rover failed during an excursion.

They deployed or conducted 10 science experiments, including the Apollo Lunar Surface Experiments Package (ALSEP) suite of instruments, took more than 2,000 photographs and collected about 243 pounds (110 kilograms) of soil and rock samples at 22 different sites.

The Final Farewell

At the end of the third and final EVA, Cernan and Schmitt televised the unveiling of a plaque on the lunar module, which read, “Here man completed his first exploration of the Moon, December 1972 A.D. May the spirit of peace in which he came be reflected in the lives of all mankind.”

Cernan took humankind's final (to date) step off the Moon at 5:40 UT on December 14. They lifted off of the Moon at 22:54 UT.

Cernan took humankind's final (to date) step off the Moon at 5:40 UT on December 14.
Challenger docked with America at 1:10 UT on December 15. Some four hours later, the lunar module was jettisoned and subsequently sent crashing into the lunar surface at about 3,800 mph (1.7 kilometers per second).

After another day and a half in lunar orbit, during which the astronauts released a subsatellite like the ones launched by Apollo 15 and 16, they fired their engine to return to Earth. En route, Evans conducted an hour-long spacewalk to retrieve camera and lunar sounder film from the Scientific Instrument Module bay.

The Apollo 17 capsule splashed down in the Pacific Ocean on December 19, 1972 at 19:24:59 UT (2:24:59 p.m. EST) after a mission elapsed time of 301 hours, 51 minutes, 59 seconds. The splashdown point was 403 miles (648 kilometers) SE of the Samoan Islands and 4 miles (6.5 kilometers) from the recovery ship USS Ticonderoga.

This was the second spaceflight for Cernan and the first for Evans and Schmitt. The backup crew for this mission consisted of John Young, Stuart Roosa and Charles Duke. Command module capsule America is on display at the Johnson Space Center in Houston, Texas.

- Credit: NASA