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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"

An Airplane in Front of the Moon

03/07/2018

An Airplane in Front of the Moon
Image Credit: Ji-Hoon Kim / NASA APOD

If you look closely at the Moon, you will see a large airplane in front of it. Well, not always. OK, hardly ever. Actually, to capture an image like this takes precise timing, an exposure fast enough to freeze the airplane and not overexpose the Moon -- but slow enough to see both, a steady camera, and luck -- because not every plane that approaches the Moon crosses in front. Helpful equipment includes a camera with fast continuous video mode and a mount that automatically tracks the Moon. The featured fleeting superposition was captured from Seoul, South Korea two weeks ago during a daytime waxing gibbous moonrise. Within 1/10th of a second, the airplane crossing was over. Follow APOD on: Facebook, Google Plus, Instagram, or Twitter