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Supermoon 2021: 6 facts you need to know about the phenomenon

This infrequent lunar occurrence is worth staying up for.


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Here are 6 facts you need to know about supermoons.



A supermoon occurs when the Moon is at the closest point to Earth in its orbit, also known as its perigee.

Astronomers call supermoons “perigean full moons.”


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Supermoons reach their peak late at night (11:31 p.m. Eastern for the April 26 supermoon). The well-known “Moon illusion,” which makes the Moon look larger near the horizon, means the supermoon may be more impressive around moonrise.

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The term “supermoon” comes from astrology, not astronomy.

It was coined by astrologist Richard Nolle in 1979, who predicted (incorrectly) that a supermoon would cause natural disasters.

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Astrological doomsaying aside, supermoons can increase the risk of tidal flooding. The Moon’s effect on tides is well known, and when at its closest point to the Earth, that effect is more pronounced.

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Read more stories on astronomy here.

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