Apollo 15 Mission

Surface Operations Overview

Hammer and Feather Demonstration Video Clip (2.2MB in AVI Format)

Because of the variety of surface features, the Hadley-Apennine landing site permitted extensive geological exploration. During the approximately 67 hours on the Moon, the crew conducted a 33-minute stand-up extravehicular activity (EVA) in the upper hatch of the of the lunar module as well as three EVAs totaling about 18.5 hours on the lunar surface. Improvements to the Portable Life Support System used with their space suits allowed the crew to perform longer EVAs (up to 7.5 hours) than was possible on earlier missions. During these EVAs, they performed lunar rover traverses totaling nearly 28 kilometers, collected samples at 12 locations, deployed 10 experiments, and photographed the lunar surface. The following map of the landing site shows where these activities took place.

Apollo 15 Traverse Map

First Extravehicular Activity

	Apollo 15 Lunar Module This photograph shows the Apollo 15 lunar module Falcon at its landing site on the Moon. Hadley Delta in the background rises approximately 4000 meters (about 13,000 feet) above the plain. The base of the mountain is approximately 5 kilometers (about 3 miles) away.

	The Standup EVA Commander David R. Scott, his upper body extending through the top hatch of the lunar module (LM), performed the 33-minute standup EVA. From this elevated vantage point, he described the lunar terrain, used the Sun compass to establish the location of the LM with respect to recognizable lunar features, and obtained panoramic photographs of lunar terrain and photographs of interesting distant features. This view, looking southeasterly, shows Hadley Delta. The prominent feature on the horizon in the center of the picture was called Silver Spur by the Apollo 15 crew.

	First Extravehicular Activity The first extravehicular activity began at 9:13 a.m. EDT on July 31. Activities included a 10.3-kilometer geological traverse and the deployment of lunar surface experiments. Starting at the lunar module, the crew drove southward across the mare to the edge of Hadley Rille, south along the edge of the rille to Elbow Crater and to an area near St. George Crater. The return route was past Elbow Crater and directly across the mare to the lunar module. The EVA lasted approximately 6 hours, 33 minutes, ending at 3:46 p.m.

Activities at the Lunar Module Site

Collecting the Contingency Sample

Apollo 15 was the last mission on which a contingency sample was collected. The sampling consisted of seven samples taken approximately 12 meters west of the lunar module footpad. The site is a small flat area between two subdued 1-meter-diameter craters. This sample was collected to ensure that some lunar material would be returned for study on Earth in the event that an emergency required the rapid, unplanned end to the EVA.

Deploying the Lunar Rover

This mission was the debut of the Lunar Rover. To get it to the Moon, the rover was folded into a compact bundle and placed in a storage bay in the descent stage of the LM. Once there, the astronauts had to unload and unfold it before it could be used.

Undoing the Rover An artist's conception showing the Apollo 15 crew performing deployment of the rover on the lunar surface. The figure on the left represents astronaut James B. Irwin, who maintains a constant pull on the deployment cable to help the rover unfold, while astronaut Scott, right, pulls the tapes that lower the rover to the surface.

Unfolding the Rover An artist's conception showing the final steps of readying the Apollo 15 lunar rover for use on the lunar surface. The tasks depicted here include setting up of the seats and releasing the rover from the LM.

Preparing the Rover This photograph shows an astronaut loading up the lunar rover in preparation for a traverse

Deployment of the TV Camera
On the Apollo 15 mission, the television camera was mounted on the lunar rover instead of the surface. This allowed live coverage of activities at the remote stations, in addition to the LM site. The camera is mounted on the mast in the center of this picture. The camera could be controlled by the ground through a communications linkup using the antenna at the right.

The Geologic Traverse

Traverse Map

Station 1 - Elbow Crater
Station 1 was located on the east flank of Elbow Crater. Here the astronauts performed radial sampling (collecting samples at varying distances from the crater, corresponding to material ejected from different depths below the surface when the crater formed), gathered documented samples, and performed panoramic photography.

Station 2 - St. George Crater
Station 2 was located on the northwestern flank of St. George Crater near the base of the Apennine Front. The astronauts gathered samples, obtained a double-length core tube sample, and performed stereopanoramic and 500-millimeter photography.

Station 3
On the return traverse from Station 2 to the experiment deployment site, the astronauts made an unscheduled stop and collected one sample. This location was designated Station 3.

The Apollo Lunar Surface Experiments Package

After returning to the LM, the astronauts unloaded and deployed the Apollo Lunar Surface Experiments Package (ALSEP). This was deployed at a site designated Station 8, approximately 110 meters north-northwest of the lunar module. The ALSEP consisted of the following experiments: the Heat Flow Experiment, the Lunar Surface Magnetometer, the Passive Seismic Experiment, the Cold Cathode Gage, the Solar Wind Spectrometer, the Suprathermal Ion Detector Experiment, the Lunar Dust Detector, and the Laser Ranging Retroreflector. Deployment went well for the most part, but there were problems with the Heat Flow Experiment.

	The Lunar Surface Drill The lunar surface drill, used for the first time on Apollo 15, provided a means for one crewman to emplace the Heat Flow Experiment probes below the lunar surface and collect a subsurface core. The performance of the drill was good. However, full depth penetration with the bore stems was a problem, and extracting the core stems proved difficult.

	Deploying the Solar Wind Composition Experiment The Solar Wind Composition experiment was deployed approximately 15 meters southwest of the lunar module. Total exposure time for the foil was 41 hours and 8 minutes. Upon retrieval, the foil had to be rolled manually.

Second Extravehicular Activity

The second extravehicular activity began at 7:49 a.m. EDT August 1 and ended at 3:01 p.m. the same day. A prime activity was a 12.5-kilometer traverse southeast across the mare and near Index, Arbeit, Crescent, Dune, and Spur craters along the base of the Apennine Mountains. The return traverse closely followed the outbound route. After unloading the samples, the astronauts made a second trip to the ALSEP site to perform some additional tasks. The duration of the second EVA was approximately 7 hours, 12 minutes.

The Geological Traverse

Traverse Map

Station 6 - Apennine Front
The easternmost point sampled on the Apennine Front, this site was nearly 3 kilometers east of St. George Crater and 5 kilometers southeast of the lunar module. Here, on the north-facing slope of Hadley Delta and about 90 to 100 meters above the mare surface, the astronauts performed a number of tasks. They gathered a large number of samples, including a core tube sample and a special environmental sample from a trench. The special environmental sample was stored in a special container providing extra protection against atmospheric and biologic contamination. They also performed panoramic and 500-millimeter photography.

Station 6A - Apennine Front
Station 6A was the highest location explored on the Apennine Front. It was an intermediate stop made en route to Station 7. The boulder that marked this stop was located about 250 meters south-southeast of Spur Crater. The astronauts collected six samples and performed panoramic photography.

Station 7 - Spur Crater
At this station, located on the rim of Spur Crater, the crew gathered selected samples and a comprehensive soil sample. In all, 93 samples were collected, including the sample that became known as the "Genesis Rock." Panoramic photography was also performed at this site.

Station 4 - Dune Crater
This station was on the south rim of Dune Crater. This stop was made on the return leg of the traverse rather than the outbound leg as originally planned. The crew collected samples and performed panoramic photography.

Station 8 - The ALSEP Site
The site of the ALSEP experiment deployment was designated Station 8. It was located approximately 125 meters northwest of the LM. Sampling in this area included comprehensive geologic samples and a special environmental sample gathered from a trench.

Other EVA Activities

At the end of this EVA the astronauts finished some experiment deployment tasks that had not been completed during the first EVA. Among them were the emplacement of the heat flow probe, the drilling of a deep-core sample hole, and performing a series of soil mechanics measurements with the Self-Recording Penetrometer. The flag was also deployed on this EVA.

The Self-Recording Penetrometer 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 that rests on the surface, the upper housing assembly that contains the recording drum, and the shaft that joins them and is used for the penetration. The penetrometer is the device with the cylinder on top at the far left of the tool rack.

Placing the Flag Astronaut David R. Scott gives a military salute while standing beside the deployed U.S. flag during the second Apollo 15 lunar surface EVA at the Hadley-Apennine landing site.

Third Extravehicular Activity

The third EVA began at 4:52 a.m. EDT on August 2, about 1.5 hours late to allow the crew to get some additional rest. This EVA included a 5.1-kilometer traverse west to Scarp Crater and northwest along the edge of Hadley Rille, and east across the mare to the lunar module. The EVA was shortened to approximately 4 hours and 50 minutes to meet the liftoff time line.

The Geological Traverse

Traverse Map

Station 8 - ALSEP Site
At the beginning of this EVA, the astronauts made another visit to the ALSEP site where they recovered the deep core sample and photographed the lunar rover in operation.

Station 9 - Hadley Rille
Station 9 was situated approximately 1.4 kilometers west of the LM and 300 meters east of Hadley Rille. The astronauts collected samples and performed panoramic photography tasks.

Station 9A - Hadley Rille
One hundred and three samples were collected from an area of about 30 by 75 meters at this site, which was located at the edge of Hadley Rille, about 1.8 kilometers west of the LM. A double-length core tube sample was part of this extensive sampling. Photographic tasks at this site included 500-mm and stereoscopic panoramic photography.

Station 10 - Hadley Rille
Although samples were collected, this station was primarily a stop for photography. This site was about 200 meters north-northwest of Station 9A. This offset distance provided a base for obtaining stereoscopic 500-mm and panoramic photography.

Station 8 - ALSEP Site
The Apollo 15 crew made one last stop at Station 8 to recover the drill core sample and to perform some final photographic tasks at the site.

Other EVA Activities

After returning to the lunar module, the astronauts prepared for leaving the Moon. They retrieved the Solar Wind Composition foil and canceled the First Day Issue stamp. They performed the hammer and feather drop. They parked the lunar rover and positioned it to obtain color television coverage of the LM ascent. As their final act, they placed a memorial to "fallen astronauts" in a small crater about 20 feet north of the parking site.

Dropping the Hammer and Feather Video Clip (2.2 MB in AVI Format) Astronaut David R. Scott watches a geological hammer and feather hit the lunar surface simultaneously in a test of Galileo's law of motion concerning falling bodies. Scott released the hammer from his right hand and the feather from his left at the same instant.

The Memorial for Fallen Astronauts A close-up view of a commemorative plaque left on the Moon at the Hadley-Apennine landing site in memory of 14 NASA astronauts and Soviet cosmonauts. Their names are inscribed in alphabetical order on the plaque. The plaque was placed in the lunar soil by astronauts Scott and James Irwin. The tin, manlike object represents the figure of a fallen astronaut/cosmonaut.

End of the Apollo 15 Mission

This is a photographic replica of the plaque that the Apollo 15 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.

EVA 2 Voice Transcript (Apollo Lunar Surface Journal)

Apollo Lunar Surface Journal - Apollo 15 Mission
This link connects to transcripts of the radio transmissions of the Apollo 15 astronauts during their time on the lunar surface. Located at NASA Headquarters, they are the work of Eric Jones who has added explanatory notes and comments from the astronauts.

Apollo 15 Mission

Surface Operations Overview

Activities at the Lunar Module Site

The Geologic Traverse

The Apollo Lunar Surface Experiments Package

The Geological Traverse

Other EVA Activities

APOLLO MISSIONS