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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"

Looking Back on an Eclipsed Earth

30/08/1999

Looking Back on an Eclipsed Earth
Image Credit: CNES / NASA APOD

Here is what the Earth looks like during a solar eclipse. The shadow of the Moon can be seen darkening part of Earth. This shadow moves across the Earth at nearly 2000 kilometers per hour. Only observers near the center of the dark circle see a total solar eclipse - others see a partial eclipse where only part of the Sun appears blocked by the Moon. This spectacular picture of the 1999 August 11 solar eclipse was one of the last ever taken from the Mir space station, as Mir is being decommissioned after more than ten years of productive use.