While most people are familiar with the term “Blue Moon,” a “Black Moon” is an equally rare phenomenon, and will occur this week.
According to Time and Date, a “Black Moon” is actually inverse of a “Blue Moon.” It is either defined as the second new moon within a calendar month, or as the third new moon in a season of four new moons.
This month’s “Black Moon” falls under the former category, and will occur on Monday night, according to NASA. It follows the first new moon of the month, which occurred Dec. 1.
A “Blue Moon,” by contrast, occurs on the second full moon of the same month, or the third full moon during a season where there are four full moons.
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According to Space.com, Black Moons occur roughly every 29 months, around the same frequency as Blue Moons.
By the “two moons in a month” definition, there will not be a “Black Moon” in 2025, and there actually won’t be a “Blue Moon” either, as there are only 12 full moons and 12 new moons during the calendar year.
There will be a “Black Moon” according to the latter definition of the term, as there will be four new moons during astronomical summer in the year 2025. The “Black Moon” would take place on Aug. 23.
U.S. & World
The next time Earth will see two new moons within the same calendar month will be in Aug. 2027, according to Calendar12.com.
