BBC Sky at Night

THE BIG THREE

DON’T MISS

Perigee full Moon and the ‘Moon illusion’

BEST TIME TO SEE: Evenings of 14-16 June

The lunar orbit is elliptical and over time this means the distance between Earth and the Moon varies. As you would expect, the apparent diameter of the Moon varies over its orbit because of this distance change. Apogee describes when the Moon is furthest from Earth, perigee when nearest. When it’s closest, the Moon’s apparent size is around 34 arcminutes, while at apogee the Moon’s apparent size is around 30 arcminutes.

Apogee and perigee have no connection

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