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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"

A Twilight Occultation

10/12/2010

A Twilight Occultation
Image Credit: Doug Zubenel / NASA APOD

A thin, one day old crescent Moon hugged the western horizon after sunset on Monday, December 6. The Moon also occulted or passed in front of Mars. But only some well-placed skygazers along a band through North America were able to catch this lunar occultation's final act in fading twilight. For example, this telephoto image nicely captures Mars as a pinprick of light, shortly after it emerged from behind the crescent Moon's sunlit edge. With a tangle of tree limbs in silhouette, the luminous skyview is from De Soto, Kansas in the central US. Of course, this month's upcoming total lunar eclipse will entertain a much wider audience of Moon enthusiasts during the night of December 20/21. Call for Security Camera Videos: Recent Fireball over the United Kingdom