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The Moon

The Moon is Earth’s only natural satellite—a rocky, cratered body about one‑quarter the diameter of Earth, orbiting at an average distance of approximately 384,400 km. It influences tides, stabilizes Earth’s axial tilt, and was formed about 4.5 billion years ago following a collision between Earth and a Mars-sized object.

Source: science.nasa.gov

APODs including "The Moon"

Apollo 12 Visits Surveyor 3

05/10/2003

Apollo 12 Visits Surveyor 3
Image Credit: NASA Astronomy Picture of the Day

Apollo 12 was the second mission to land humans on the Moon. The landing site was picked to be near the location of Surveyor 3, a robot spacecraft that had landed on the Moon three years earlier. In the above photograph, taken by lunar module pilot Alan Bean, mission commander Pete Conrad jiggles the Surveyor spacecraft to see how firmly it is situated. The lunar module is visible in the distance. Apollo 12 brought back many photographs and moon rocks. Among the milestones achieved by Apollo 12 was the deployment of the Apollo Lunar Surface Experiments Package, which carried out many experiments including one that measured the solar wind.