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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"

The Great Wall by Moonlight

13/03/2015

The Great Wall by Moonlight
Image Credit: Francis Audet / NASA APOD

Last Friday, an almost Full Moon rose as the Sun set, over this mountainous landscape north of Beijing, China. Also near apogee, the farthest point in its elliptical orbit around planet Earth, it was this year's smallest and faintest Full Moon. The Jiankou section of the Great Wall of China meanders through the scene, the ancient Great Wall itself the subject of an older-than-the-space-age myth that it would be visible to the eye when standing on the lunar surface. But even from low Earth orbit, the large scale artifact of human civilization is very difficult to identify. At its farthest from our fair planet, the Moon shines brightly in the twilight sky though, posing in the faint, pinkish band known as the antitwilight arch or the belt of Venus.