The half-illuminated moon, often called a half moon, is a quarter of the way along its cycle from new moon (dark) to crescent moon to full moon (fully illuminated) and back again.
The half-illuminated moon, often called a half moon, is a quarter of the way along its cycle from new moon (dark) to crescent moon to full moon (fully illuminated) and back again. NASA
The half-illuminated moon, often called a half moon, is a quarter of the way along its cycle from new moon (dark) to crescent moon to full moon (fully illuminated) and back again. NASA

Why does a ‘first-quarter’ moon show half of it?

August 16, 2015 04:00 PM

UPDATED August 16, 2015 09:33 PM

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