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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"

Red Moon Triple

29/10/2004

Red Moon Triple
Image Credit: Fred Espenak / NASA APOD

Some thought of baseball and some thought of Halloween during October 27th's widely viewed total lunar eclipse. Sliding through Earth's shadow, the Moon turned haunting shades of red and orange during the eclipse's total phase. The reddish hues are caused by sunlight scattered and refracted by the atmosphere into the Earth's otherwise dark central shadow region. Enjoying the show from Dunkirk, Maryland, USA, astronomer Fred Espenak recorded the images used in this composite photo. The picture shows the Moon at the beginning (right), middle (center) and end (left) of totality which lasted about 81 minutes. Though lunar eclipses can occur twice a year, this eclipse is perhaps remarkable for being the first total lunar eclipse to occur during a World Series baseball game.