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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"

Illuminated Cloud Trails Above Greece

15/03/2010

Illuminated Cloud Trails Above Greece
Image Credit: Chris Kotsiopoulos / NASA APOD

It may appear to be day, but it's night. Those wondrous orange streaks may appear to be rays from the setting Sun, but they're actually thin clouds illuminated by the Moon as they quickly streaked toward the distant horizon. The thick clouds on the far left may appear to have many layers, but actually they are just a few simple clouds captured on numerous separate exposures. What is surely true, though, is that the above time lapse image sequence was taken over two hours, about two weeks ago, in Sounio, Greece. Also, those really are star trails swirling around the north star Polaris on the upper right of the image. But what about the building in the foreground? It may appear to be a famous ancient structure, but it's actually a small deserted church built only last century. Your opinion requested: Is APOD a blog?