Apollo 16 Mission
Service Operations Overview
During their 71 hours on the Moon, the Apollo 16 crew conducted three extravehicular activities totaling about 20.3 hours on the lunar surface. These EVAs included performing lunar rover traverses totaling 26.7 kilometers, collecting lunar samples at 11 sites, deploying or performing nine experiments, and examining and photographing the lunar surface. The following map of the landing area shows where these activities took place.
First Extravehicular Activity
|The photograph shows the Apollo 16 lunar module (LM) on the Moon. Just below the flag is the Modularized Equipment Stowage Assembly, where experiments and tools are stored. An additional payload storage area is on the lower left side of the LM.|
Activities at the Lunar Module Site
Deploying the Apollo Lunar Surface Experiments Package
The Apollo Lunar Surface Experiments Package (ALSEP) was unloaded and transported approximately 95 meters southwest of the lunar module to a site designated Station 3/10. One minor problem occurred while the experiments package was being transported to the site when subpackage 2 fell off the carrier bar. No damage was done to the package; later, however, the Heat Flow Experiment was rendered inoperable during emplacement. The rest of the experiments were deployed without further trouble.
The Geologic Traverse
Station 1 - Plum Crater
Station 1 was approximately 1400 meters west of the LM near the rim of Plum Crater. The astronauts collected samples and performed panoramic and stereographic photography.
Station 2 - Buster Crater
This station was located about 550 meters west of the LM on the southern rim of Buster Crater. Activities at this stop included a Lunar Portable Magnetometer measurement and panoramic and 500-millimeter photography. Samples were also collected; however, a planned sampling of the rim of nearby Spook Crater was skipped.
Station 3/10 - LM/ALSEP Site
This station included the area around the LM and the ALSEP experiment deployment site and was visited several times. On this visit, the crew performed the "Grand Prix" with the lunar rover, retrieved a 2.6-meter-deep core sample, and armed the Active Seismic Experiment mortar package.
Other EVA Activities
Back at the LM, the astronauts deployed the Solar Wind Composition Experiment, gathered samples, and performed photography. Also during this EVA, 19 small explosive charges were fired using a "thumper," which was part of the Active Seismic Experiment.
The Solar Wind Composition Experiment was deployed about 18 meters northwest of the LM at the end of the first EVA and retrieved at the end of the third EVA. Total foil exposure time was 45 hours and 5 minutes.
Second Extravehicular Activity
During the second extravehicular activity (EVA), a geological traverse was made south of the landing site to the Cinco Crater area of Stone Mountain. The traverse covered 11.1 kilometers and included stops at six field stations. The planned Station 7 was omitted in order to spend additional time at the other stations. The total time on the surface during this EVA was 7 hours and 23 minutes, from 11:33 a.m. to 6:56 p.m. EST on April 22.
The Geologic Traverse
Station 4 - Stone Mountain (Cinco Crater)
Station 4 marked the highest point reached at Stone Mountain. The astronauts gathered samples at two locations, including a double-length core tube sample and a soil trench sample. They also performed 500-millimeter and panoramic photography and made four penetrometer measurements.
Station 5 - Stone Mountain (Slope)
This site, approximately 0.5 kilometers downslope from Station 4, was on a topographic bench about 50 meters wide. Samples were gathered, panoramic photography was performed, and a Lunar Portable Magnetometer measurement was obtained.
Station 6 - Stone Mountain (Base)
At this site on the Cayley Plain, the astronauts gathered samples and performed panoramic photography.
Station 8 - Wreck Crater
Station 8 was located near two 15- to 20-meter craters approximately 2.8 kilometers south-southwest of the lunar module. Sampling activities included collecting a double-length core tube sample and boulder samples. Panoramic photography was also obtained.
This station was just south of a 50-meter crater and northeast of Station 8. Here the crew gathered a number of different types of samples. They obtained more boulder samples, a single-length core tube sample, two special contact soil samples, and samples taken from beneath a boulder that was overturned. The usual panoramic photography was also performed.
Station 10 - LM/ALSEP Site
This was another visit to the area around the lunar module and the ALSEP site. Activities during this visit included gathering samples, taking a core tube sample, performing penetrometer measurements, and taking panoramic photographs.
Other EVA Activities
The soil mechanics trench planned for this EVA was omitted due to time constraints. However, a number of other soil mechanics tests were performed using the Self-Recording Penetrometer: four cone penetration tests at Station 4 and five cone penetrations and two plate load tests at Station 10.
The Self-Recording Penetrometer provided quantitative data on soil penetration resistance as a function of depth below the lunar surface. The device consists of the reference pad assembly, which rests on the surface; the upper housing assembly, which contains the recording drum; and a shaft, which joins the two assemblies. In this picture, the penetrometer is on the far left of the rover tool rack.
Third Extravehicular Activity
As a result of the delayed lunar landing, the time for the third EVA was reduced to 5 hours and 40 minutes, from 10:25 a.m. EST to 4:05 p.m. on April 23. To save time, several planned stops on the geological traverse to North Ray Crater were omitted, with the work concentrated at three field stations. The traverse covered 11.4 kilometers.
The Geologic Traverse
Station 11/12 - North Ray Crater (House Rock)
This site was located on the southeast rim of North Ray Crater, several kilometers north of the lunar module. The astronauts gathered samples and performed 500-millimeter and panoramic photography. Far-field polarimetric photography was also performed as planned, but near-field polarimetric photography was eliminated because of time limitations.
Station 13 - North Ray Crater (Shadow Rock)
Samples gathered at this stop at the base of Smoky Mountain included some special samples that were placed in padded bags to reduce abrasion of the sample surfaces. The crew also made another Lunar Portable Magnetometer measurement and performed panoramic photography.
Station 10' (10 Prime) - Lunar Module/ALSEP Site
On their return from the traverse, the crew made another visit to the ALSEP experiment site to complete the activation of the experiment package. At another site in the lunar module/ALSEP area, designated 10', they also gathered samples, including a double-length core tube sample, and performed 500-millimeter and panoramic photography.
Other EVA Activities
Back at the lunar module, the crew gathered some additional samples and retrieved the Solar Wind Composition foil, the Cosmic Ray Detector, and the film from the Far UV Camera/Spectrograph. Also, as part of final preparations for leaving the Moon, they moved the lunar rover to its final parking site away from the lunar module. Because Stations 14 through 17 were eliminated from the abridged time line, two additional magnetometer measurements were made and some additional samples were collected at that location.
The Lunar Portable Magnetometer was used once each on EVA 1 (Station 2) and EVA 2 (Station 5), in addition to its measurements at Station 13 and the final rover parking site on this EVA. This instrument was used to measure the magnetic field at locations along the traverse of the lunar surface. The deployment and operation of the magnetometer was normal in all respects.
End of the Apollo 16 Mission
This is a close-up of the plaque the Apollo 16 astronauts left on the Moon during their lunar landing mission. The 7" × 9" stainless-steel plaque was attached to the ladder on the landing gear strut on the lunar module's descent stage.
Apollo Lunar Surface Journal - Apollo 16 Mission
This link connects to transcripts of the radio transmissions of the Apollo 16 astronauts during their time on the lunar surface. Located at NASA headquarters, these transcripts are the work of Eric Jones, who has added explanatory notes and comments from the astronauts.