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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"

A Total Solar Eclipse Close-Up in Real Time

03/03/2024

Video Credit: Jun Ho Oh (KAIST, HuboLab); Music: Flowing Air by Mattia Vlad Morleo / NASA APOD

How would you feel if the Sun disappeared? Many eclipse watchers across the USA surprised themselves in 2017 with the awe that they felt and the exclamations that they made as the Sun momentarily disappeared behind the Moon. Perhaps expecting just a brief moment of dusk, the spectacle of unusually rapid darkness, breathtakingly bright glowing beads around the Moon's edge, shockingly pink solar prominences, and a strangely detailed corona stretching across the sky caught many a curmudgeon by surprise. Many of these attributes were captured in the featured real-time, three-minute video of 2017's total solar eclipse. The video frames were acquired in Warm Springs, Oregon with equipment specifically designed by Jun Ho Oh to track a close-up of the Sun's periphery during eclipse. As the video ends, the Sun is seen being reborn on the other side of the Moon from where it departed. Next month, on April 8th, a new total solar eclipse will be visible in a thin band across North America.