Apollo 15 operations on the Lunar surface

Nine minutes and ten seconds into the burn, Program 64 started on the computer and the LM pitched forward and the crew could see the ground.

Radar observations from Earth had given the impression that the area was covered in large boulders that would make it impossible to traverse with the Rover.

Throughout the astronauts' sleep period, Mission Control had watched with some concern as the pressure inside descent stage oxygen tanks of the LM slowly dropped.

To conserve power during the night, the LM was run on a low-data-rate telemetry stream, so Mission Control could not tell the exact cause.

In the end, Flight Director Peter Frank chose to wake the crewmen an hour early and got them to turn back on the high-data-rate telemetry.

As Scott became the seventh man to step onto the lunar surface, he said: As I stand out here in the wonders of the unknown at Hadley, I sort of realize there's a fundamental truth to our nature.

And this is exploration at its greatest.After inspecting the LM, Scott began to unpack the Modularised Equipment Stowage Assembly (MESA), which was attached to the side of the LM and carried the Apollo TV camera, sample bags, batteries, CO2 scrubbers for the space suits, and other equipment needed while the astronauts were outside the spacecraft.

After Scott positioned the TV camera on a tripod so Mission Control could see the deployment of the Lunar Rover, he and Irwin began the process by pulling on two lanyards.

[1][2][3] The astronauts could not travel any farther than the distance they could walk with the remaining oxygen in their Portable Life Support Systems (PLSS).

Scott set off at 9 km/h (6 mph), slow by terrestrial standards, but due to the lowness of the chassis of the Rover and the roughness of the surface, the astronauts would say it seemed quite quick.

In A Man on the Moon, Andrew Chaikin writes that Dale Jackson of USGS was having dinner with some astronauts that night in Houston and happily proclaimed that "they did everything but fuck that rock."

Other samples in the area were made using a specially designed rake with tines spaced 1 cm apart to collect small pebbles from the regolith.

Mission Control announced that it had decided to cancel a planned stop at a crater named Flow due to time constraints.

Back at Falcon, Scott and Irwin set about deploying the Apollo Lunar Surface Experiments Package (ALSEP).

Scott would drill the holes for the heat-flow experiment and put in the probes, while Irwin would set up the rest of the equipment.

The target of the second EVA was Mount Hadley Delta again, but the crew drove via a more direct route and to a site east of where they had travelled the previous day.

The first stop of the day, Station 4 was cancelled to give them more time to finish the drilling the holes for the heat flow experiment.

Mission Control called up and said they would like the crew to dig a trench to study the soil mechanics and take a core sample.

At first Irwin thought he had kicked up some green soil, but Scott found it was just caused by the visors of the helmets which were coated gold.

With time running out, and the walk-back constraint approaching, the geology backroom decided that they wanted the astronauts to collect as many small fragments as they could from the area.

Irwin's camera jammed after acquiring a panorama of the area, forcing Scott to take all the remaining documentation photography.

This process however would cause the drill bit sections to come apart, meaning that what Scott was really doing was creating a new obstruction below the surface without realizing it.

Post-flight analysis would find that the drill design was flawed, with the flutes too close together at the joint joining the sections of the stem.

At 2.4 meters, Scott decided that this was far enough as they were well below the depth of the heat-flow probes, the main reason for taking the core sample.

Any attempt to tilt up or down would cause it to flop down, leaving it pointing uselessly at the ground and requiring an astronaut to repoint it.

After making a 16 mm film of the Rover driving for the engineers on Earth, they set off for the main target of their last EVA, Hadley Rille.

As Irwin took the site panorama, Scott used the 500 mm telephoto lens to image the far side of the Rille, which was about 0.6 mi (1 km) across.

They were looking for layering in the wall of the Rille, which could help geologists to find if the lava flows that had filled Palus Putredinis came in one go or over time.

And I guess one of the reasons we got here today was because of a gentleman named Galileo, a long time ago, who made a rather significant discovery about falling objects in gravity fields.

In all figures, X indicates sample locations, 5-digit numbers are LRL sample numbers, rectangle is lunar rover (dot indicates TV camera), black spots are large rocks, dashed lines are crater rims or other topographic features, and triangles are panorama stations.