Apollo Program (continued):
Apollo missions brought back about 382 kg of samples of rocks and regolith spending about 25 human days on the Lunar surface. These samples are the basis for continuing scientific study.
Ian Crawford, The scientific legacy of Apollo, Astronomy & Geophysics, Volume 53, Issue 6, December 2012, Pages 6.24–6.28,
Lunar surface changes very slowly so it can be used to understand terrestrial evolution. The astronauts footprints will likely persist for 100 million years barring direct large meteoroid hits. Big Bertha, a breccia and the largest lunar sample collected during Apollo 14, may contain a 2-centimeters of material originally formed on Earth, as such it would be the oldest existing Earth rock.
Analysis of the age of samples and lunar cratering has made it possible to track the density of cratering on lunar surfaces of known age over time to infer the age of surfaces of other nearby terrestrial objects based on their crater density.
Lunar regolith contains a record and depth of interaction with solar wind particles, cosmic rays, and meteoroid impact.
The calibration of remote sensing satellites using known materials from known sites enables the remote exploration of other areas of the Moon.
Passive and active seismology shed light on the thickness of the regolith and underlying lava in a variety of locations.
The magnetism of the Moon at various locations and within Lunar samples was measured to better understand the changing magnetic fields of the Moon.
The exact, changing distance between the Moon and Earth from three Lunar locations is being measured using Laser Ranging Retroreflector. Lunar librations (waggles) as it rotates and changes in Earth’s rotation are tracked.
