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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 14 Heads for Home

01/02/2020

Apollo 14 Heads for Home
Image Credit: NASA Astronomy Picture of the Day

When leaving lunar orbit in February 1971, the crew of Apollo 14 watched this Earthrise from their command module Kitty Hawk. With Earth's sunlit crescent just peeking over the lunar horizon, the cratered terrain in the foreground is along the lunar farside. Of course, while orbiting the Moon, the crew could watch Earth rise and set, but the Earth hung stationary in the sky over Fra Mauro Base, their landing site on the lunar surface. Rock samples brought back by the Apollo 14 mission included a 20 pound rock nicknamed Big Bertha, later determined to contain a likely fragment of a meteorite from planet Earth.