Stargazers and moon watchers will be watching the sky this week when a second new moon of the month appears -- sort of -- on Friday.

The phenomenon, which occurs roughly every 32 months, is referred to as a "black moon," according to space.com.

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A new moon is when the moon's Earth-facing side is engulfed in darkness, so it could be slightly difficult to see.

There is typically one full moon and one new moon each month. A second full moon in a month is called a "blue moon."

The new moon officially occurs at 8:11 p.m. Friday in the Western Hemisphere, according to space.com.