How Do the Phases Get Their Names?

The Phases of the Moon.
Click on image for full size (15K GIF)

When the Moon appears smaller than a quarter, we call it a crescent. When the Moon appears larger than a quarter, we call it gibbous. When the moon is getting bigger (phases New to Full) it is waxing. When it is getting smaller (phases Full to New) it is waning.

For example, if today the Moon were a waxing crescent, then we would only see a little piece of the half of the Moon that is reflecting sunlight. But tomorrow, that piece would be bigger. If today the Moon were a waning gibbous, then we would see a big piece of the half of the Moon that is reflecting sunlight. But tomorrow, that piece would be smaller.

There is an easy way to tell if a crescent Moon is growing or shrinking. If the crescent Moon looks like a "C" (C for collapsing!), it is shrinking.

Nicknames for the Full Moon

Last modified October 19, 2005 by Randy Russell.
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How Do the Phases Get Their Names?

The Phases of the Moon. Click on image for full size (15K GIF)

The Phases of the Moon.
Click on image for full size (15K GIF)