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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"

Dark Lunar Eclipse

30/08/2007

Dark Lunar Eclipse
Image Credit: Martin Pugh / NASA APOD

The Moon passed close to the center of Earth's shadow on August 28th. Seen best by skywatchers in western North America, and the Pacific region, the resulting total lunar eclipse was a dark one, lasting about 90 minutes. In this telescopic image taken near mid totality from Yass, NSW Australia, the 85 kilometer wide ray crater Tycho lies near the top right of the shadowed lunar surface. Of course, even during a total lunar eclipse,the Moon is not completely dark. Instead the Moon remains visible during totality, reflecting reddened light filtering into the Earth's shadow. The light comes from all the sunsets and sunrises, as seen from the lunar perspective, around the edges of a silhouetted Earth.