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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"

Comet and Lightning Beyond Bighorn Mountains

27/07/2020

Comet and Lightning Beyond Bighorn Mountains
Image Credit: Kevin Palmer / NASA APOD

Normally, Steamboat Point looks cool -- but not this cool. Every day, the iconic peak of the Bighorn Mountains is an interesting sight, in particular from US Highway 14 in Wyoming. On some rare days, the rocky vertical ridges look even more incredible when seen in front of a distant lightning storm. Earlier this month, though, something even more unusual happened -- the naked-eye Comet NEOWISE rose above it in the middle of the night. Just as a distant lightning storm was occurring in the background. Recognizing a rare opportunity, a determined astrophotographer spent a sleepless night capturing over 1400 images of this unusual triple conjunction. The featured image is among the best of them, with the foreground lit by the Moon off to the right. Comet C/2020 F3 (NEOWISE) is now headed back to the outer Solar System, destined to return only in about 6700 years. Comet NEOWISE Images: July 26 || 25 || 24 || 23 || 22 || 21 || 20 || 19 || 18 || 17 || 16 || 15 || 14 || 13 || 12 || 11 || 10 & earlier ||