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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"

Perseids from Perseus

18/08/2026

Perseids from Perseus
Image Credit: Jakub Kuřák / NASA APOD

This was a good year for the Perseids meteor shower. A key reason was the Moon was absent from lighting up Earth's night sky so that more meteors were visible than usual. Where was the Moon? It was busy visiting the Sun. Near the Perseids peak, the Moon moved directly in front of the Sun and created a total solar eclipse visible from Greenland and Spain. The Perseids occur when the Earth collides with a stream of Sun-orbiting debris cast off by Comet Swift-Tuttle. Perseid meteors, although typically only the size of a sand grain, tend to be fast and bright because Swift-Tuttle's debris orbits the Sun in a direction partly opposite Earth's orbital motion. In the featured image compilation, accumulated over several nights from Jizerka in the Czech Republic, the Perseids meteor streaks can be traced back to a single location on the sky -- its radiant in Perseus. Gallery: Perseids Meteor Shower of 2026