The blue moon’s equally rare cousin, the black moon, will rise in the Colorado sky Monday night, but you won’t be able to see it.
While a blue moon is the second full moon in a month, the black moon is the second new moon in a month – or the third new moon in a season with four, rather than a typical three – according to time and date.
New moons are fairly common, occurring about once every four weeks, but according to time and date they only appear twice in the same month, about every 29 months. The next monthly black moon will not occur until August 31, 2027.
Seasonal black moons are slightly rarer, occurring about once every 33 months. The next seasonal black moon will rise on August 23, 2025.
December’s second new moon rises Monday at 3:27 PM Mountain Time, or 10:27 PM Universal Time, according to the US Naval Observatory.
Unfortunately, tonight’s black moon, like any other new moon, will be invisible in the sky.
New moons are created when the moon is between Earth and the sun, meaning the illuminated side of the moon faces away from Earth and appears to be missing from the sky. according to NASA.
That’s the opposite of a full moon, where the moon is on the opposite side of the Earth from the sun and is fully illuminated, NASA scientists said.
Another reason why the black moon cannot be seen is that it occurs during the moon’s orbit, when it passes through the same part of the sky as the sun and gets lost in the glare of daylight, according to Time and Date.
The only time a new moon can be seen in the sky is during a solar eclipse, when it becomes visible in silhouette.
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