The Moon is Earth's only natural satellite and the first world beyond Earth visited by people. Soviet robotic missions opened the era of close lunar exploration in 1959, while NASA's Apollo Moon Landings placed twelve astronauts on the surface between 1969 and 1972. Those crews returned 382 kilograms of rock and soil, deployed instruments, and photographed the terrain from orbit and on the ground.

Apollo and later missions established a detailed geologic history: ancient highland crust, enormous impact basins, basaltic plains formed by volcanic eruptions, and a surface continually broken down by micrometeorites. Clementine, Lunar Prospector, the Lunar Reconnaissance Orbiter, and other international missions extended that record globally and strengthened evidence for water ice in permanently shadowed polar regions. The modern Moon is therefore an extensively measured planetary body, not a place known only through a few historic photographs.

Its vast image archive has also made the Moon a recurring setting for claims about artificial structures, censored photographs, and unexplained objects seen by astronauts. Some Apollo audio and imagery contain observations that were uncertain in the moment, but uncertainty in a transcript or frame does not itself identify an exotic object. Edgar Mitchell, the Apollo 14 lunar-module pilot, later spoke publicly about his belief that extraterrestrial visitation had occurred; he did not claim to have encountered aliens during his Moon mission.

The Moon's anomaly record matters because raw mission material, later interpretation, and popular mythology are unusually intertwined. Official archives allow many claims to be checked against original photography, transcripts, spacecraft geometry, and mission timelines. The lunar record continues to grow through new landers and orbiters, while claims of bases, ruins, or a concealed non-human presence remain unsupported by the accumulated exploration data.