Apollo 17 Third Extravehicular Activity
The Third Extravehicular Activity
The third extravehicular activity (EVA) began at 5:25 p.m. EST on December 13. Again the emphasis was on sampling. The major objective was to sample several large boulders near the base of the North Massif. Tracks along the massif showed that these boulders had rolled down from high on the massif, allowing the crew to sample massif material that would otherwise have been inaccessible. As with South Massif on EVA 2, material in the North Massif was sampled in the expectation that it would contain material that formed very early in the Moon's history and deep in the crust. Four major sampling stops and four minor sampling stops were made on the traverse. One additional stop, Station 10, had been planned but was eliminated to allow more time for some unfinished mission tasks. The EVA lasted 7 hours and 15 minutes, ending at 12:40 a.m. on December 14. The traverse covered a distance of about 12.1 kilometers.
The Geologic Traverse
Traverse Map
Surface Electrical Properties Site
As with EVA 2, the third EVA began with a stop at the Surface Electrical Properties Experiment site. The crew activated the experiment, but attempts to make additional measurements with this equipment during EVA 3 were unsuccessful.Station 6 - North Massif
Station 6 was on the south slope of the North Massif, approximately 250 meters north of the break in slope between the valley floor and the massif. Here the crew made a traverse gravimeter measurement, gathered samples, including a single-length core tube sample and a rake sample, and performed documentary, panoramic, and 500-millimeter photography.Station 7 - North Massif
This station was located at the base of the North Massif, just above the break in slope between the valley floor and the massif. The crew gathered samples and performed documentary and panoramic photography at this location.Station 8 - Sculptured Hills
Station 8 was near the base of the Sculptured Hills, south of Wessex Cleft and about 4 kilometers northeast of the lunar module. Activities at this site included two traverse gravimeter measurements; sampling, including rake and trench samples; and documentary and panoramic photography.Station 9 - Van Serg Crater
A number of activities were performed at this last station on the geological traverse. An explosive charge for the Lunar Seismic Profiling Experiment was deployed. Two more traverse gravimeter measurements were taken. Samples, including a trench sample and a double-length core tube sample, were collected. The astronauts also performed documentary, panoramic, and 500-millimeter photography. Finally, they removed the data storage electronic assembly from the Surface Electrical Properties Experiment receiver.LRV Stops
Four additional sampling stops, denoted as stations LRV-9 to LRV-12 on the traverse map, were made to obtain additional samples between the main traverse stops. Two of these were made between the Surface Electrical Properties site and Station 6, one was made between Stations 7 and 8, and one was made between Station 9 and the lunar module.Other EVA Activities
The astronauts also performed several additional tasks during this EVA. Early in the EVA, they recovered the Lunar Surface Cosmic Ray Experiment plates. They also made three additional traverse gravimeter measurements at the lunar module. More photographs were taken and the last two explosive charges for the Lunar Seismic Profiling Experiment were deployed near the lunar module. At the end of the EVA, the Lunar Neutron Probe Experiment was retrieved and the lunar rover parked at Cochise Crater. As part of the final close-out, rock samples for distribution to other nations were collected and a plaque commemorating the Apollo landings was unveiled.
Lunar Neutron Probe Experiment Recovery
The Lunar Neutron Probe Experiment was designed to obtain data on neutron capture rates in the lunar regolith as a function of depth. The experiment was deployed northwest of the lunar module in the hole from the deep drill core. The 2-meter probe was retrieved and deactivated at the end of EVA 3 after 49 hours of exposure. The photograph shows the gold-colored Mylar transport bag and the treadle used for recovering the deep drill core.
End of the Lunar Landings
A view of the plaque left at the Taurus-Littrow lunar landing site by the Apollo 17 astronauts. The 9"× 7" commemorative plaque is made of stainless steel. It is attached to the ladder on the landing gear strut on the descent stage of the Apollo 17 lunar module Challenger.
Top of Page
Apollo 17 Table of Contents
Extravehicular Activity 1
Extravehicular Activity 2
Back to Surface Operations Overview
The Third Extravehicular Activity
Lunar Neutron Probe Experiment Recovery
End of the Lunar Landings