The blue moon’s equally rare cousin, the black moon, will rise in Colorado’s skies 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, instead of a typical three — according to Time and Date.
New moons are fairly common and happen about once every four weeks, but they only appear twice in the same month about every 29 months, according to Time and Date. The next monthly black moon won’t happen until Aug. 31, 2027.
Seasonal black moons are slightly rarer and happen about once every 33 months. The next seasonal black moon will rise on Aug. 23, 2025.
The second new moon of December will rise Monday at 3:27 p.m. Mountain Time, or 22:27 Universal Time, according to the U.S. Naval Observatory.
Unfortunately, like any other new moon, tonight’s black moon will be invisible in the sky.
New moons are created when the moon is between the earth and the sun, meaning the moon’s illuminated side is facing away from the earth and it appears to be missing from the sky, according to NASA.
That’s the opposite of a full moon, where the moon is positioned on the opposite side of the Earth from the sun and fully illuminated, NASA scientists said.
Another reason the black moon can’t be seen is that it occurs during the moon’s orbit when it passes through the same part of the sky as the sun, getting lost in the daylight’s glare, Time and Date said.
The only time that a new moon can be seen in the sky is during a solar eclipse when it becomes visible as a silhouette.
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