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Moon phase today: What the moon will look like on December 21

The moon is making its comeback.
 By 
Lois Mackenzie
 on 
An image of a full moon.
Credit: Photo by Omer Tarsuslu/Anadolu via Getty Images

The Moon is finally starting to come back into view, which means we're in a new lunar cycle. It will now be getting bigger and brighter each night as we work towards the next Full Moon.

What is today’s moon phase?

As of Sunday, Dec. 21, the moon phase is Waxing Crescent (if you're in the U.S). According to NASA's Daily Moon Observation, 2% of the moon will be lit up tonight. With so little of the Moon illuminated, there’s still nothing to see on its surface tonight.

When is the next full moon?

The next full moon will be on Jan. 3. The last full moon was on Dec. 4.


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What are moon phases?

According to NASA, the Moon takes around 29.5 days to complete one full cycle. This is known as the lunar cycle. Throughout this time, it passes through a series of phases as it orbits Earth. Although the same side of the Moon always faces us, the amount of sunlight reflecting off its surface changes, which is why it can appear fully illuminated, partly lit, or completely invisible at different points in the cycle. This process is divided into eight main lunar phases:

New Moon - The moon is between Earth and the sun, so the side we see is dark (in other words, it's invisible to the eye).

Waxing Crescent - A small sliver of light appears on the right side (Northern Hemisphere).

First Quarter - Half of the moon is lit on the right side. It looks like a half-moon.

Waxing Gibbous - More than half is lit up, but it’s not quite full yet.

Full Moon - The whole face of the moon is illuminated and fully visible.

Waning Gibbous - The moon starts losing light on the right side. (Northern Hemisphere)

Third Quarter (or Last Quarter) - Another half-moon, but now the left side is lit.

Waning Crescent - A thin sliver of light remains on the left side before going dark again.

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Lois Mackenzie

Lois Mackenzie is a freelance reporter at Mashable. Over the years she has written for many publications, covering everything from the local news to the best pair of running shoes. You can find bylines in publications including Fit&Well, Metro, and Coach magazine, usually covering deals on everything from earbuds to TVs, or guides on how to beat your half marathon time.

Lois also holds a Master's degree in Digital Journalism from Strathclyde University and obtained a Master of Arts in English Literature at the University of Aberdeen.

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