Apollo 15
The first lunar rover, a winding valley of lava, and the Genesis Rock.
Key facts
- Agency
- NASA (United States)
- Type of mission
- Crewed landing and sample return
- Target
- The Moon: Hadley–Apennine
- Launched
- 26 July 1971
- Samples returned
- 77.3 kg of rock and soil
- Status
- Completed 1971
Apollo 15 was the first of the longer, science-led missions. David Scott and James Irwin landed on 30 July 1971 at Hadley–Apennine, between the towering Apennine Mountains and a winding valley called Hadley Rille. They spent three days on the surface and drove the first Lunar Roving Vehicle almost 28 kilometres, collecting 77.3 kilograms of samples.
The Genesis Rock
On the slopes of the mountains, the astronauts spotted a white rock glinting in the sunlight. Sample 15415, nicknamed the Genesis Rock, is an anorthosite made almost entirely of plagioclase feldspar, a piece of the Moon's ancient crust. Its crystallisation age is about 4 billion years, and it remains one of the best samples of the first lunar crust.
Green glass
The crew also collected soil full of tiny emerald-green glass beads. They are droplets of lava sprayed out in fire fountains, when gas-rich magma erupted from deep inside the Moon. Gases found on these beads were among the first evidence that the lunar interior is not completely dry.
Why it matters to meteorites
Apollo 15 sampled both highland crust and mare basalt at one site, and the pair of rock types appears again and again among lunar meteorites. The astronauts were trained in field geology, and their careful notes on where each rock came from made the samples far more useful.
Key dates
| Date | What happened |
|---|---|
| 26 July 1971 | Apollo 15 launched. |
| 30 July 1971 | Scott and Irwin landed at Hadley–Apennine. |
| 31 July 1971 | The first drive of a Lunar Roving Vehicle on the Moon. |
| 7 August 1971 | The crew splashed down with 77.3 kg of samples. |
See where this mission fits among all the others in the mission timeline.
Did you know?
David Scott dropped a hammer and a falcon feather together on camera; with no air, they hit the ground at the same moment.
The tiny green glass beads in the soil are frozen droplets from volcanic fire fountains.