The "black moon," which will be visible Wednesday night, was last seen in September 2016 — and before that, in March 2014

By Jen Juneau and Alex Heigl
July 31, 2019 11:25 AM
Nicolas Economou/NurPhoto via Getty

Astronomy nerds, listen up: The black moon is upon us.

For those unfamiliar with the rare lunar phenomenon known as the black moon, it describes the second new moon in a given calendar month — something that will occur in North America at 11:13 p.m. EDT this Wednesday, just skirting the midnight cutoff for the new month. (The first new moon this month occurred on July 2.)

The Eastern Hemisphere will have to wait until after midnight on Aug. 1 for the moon, according to, meaning it qualifies as the first new moon of the month and that their black moon (as well as the U.S. West Coast’s black moon) won’t occur until the end of August.

Unfortunately, the moon will not be visible — hence the “black” part of the title — since its illuminated side will be facing away from the Earth, as is the case with most new moons.

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A black moon is the inverse of the more well-known (and sung about) “blue moon,” or the second full moon in a given calendar month. During a black moon, the waters (and the skies) get murkier here, to mix metaphors.

The last time a black moon occurred in the Western Hemisphere was in September 2016 and, before that, it hadn’t been present in this part of the world since March 2014.

Another definition of black moon means that there are no new moons in a month. As astronomer Bob Berman told Accuweather in 2016, “The phrase could also mean the third new moon when there are four in a season, which is actually also one of the definitions of a blue moon when the same thing happens to a full moon.”

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Black Moon is also the name of an American hip hop group, whose debut album Enta da Stage was released in 1993. They use the phrase as an acronym for “Brothers who Lyrically Act and Combine Kickin Music Out On Nations.” Additionally, it’s an album by Emerson, Lake & Palmer, as well as a Black Sabbath song.