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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"

Bow Tie Moon and Star Trails

08/02/2018

Bow Tie Moon and Star Trails
Image Credit: Haitong Yu / NASA APOD

On January 31, a leisurely lunar eclipse was enjoyed from all over the night side of planet Earth, the first of three consecutive total eclipses of the Moon. This dramatic time-lapse image followed the celestial performance for over three hours in a combined series of exposures from Hebei Province in Northern China. Fixed to a tripod, the camera records the Full Moon sliding through a clear night sky. Too bright just before and after the eclipse, the Moon's bow tie-shaped trail grows narrow and red during the darker total eclipse phase that lasted an hour and 16 minutes. In the distant background are the colorful trails of stars in concentric arcs above and below the celestial equator.