Autumnal equinox: Quick Facts

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Diagram showing Earth's orbit around the Sun with labeled positions for the summer solstice, winter solstice, vernal equinox, and autumnal equinox, illustrating how Earth's tilt causes the seasons.

A large tree with leaves turning orange in fall.

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First Day of Fall Wicca Autumn March September Equinox Vernal equinox Precession of the equinoxes What’s the Difference Between a Solstice and an Equinox?

The orbits of the planets and other elements of the solar system, including asteroids, Kuiper belt, Oort cloud, comet

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Nicolaus Copernicus. Nicolas Copernicus (1473-1543) Polish astronomer. In 1543 he published, forward proof of a Heliocentric (sun centered) universe. Coloured stipple engraving published London 1802. De revolutionibus orbium coelestium libri vi.

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