“Black Moon” on December 30th: The mysterious lunar phenomenon explained

“Black moon”: Which lunar phenomenon lies behind the mysterious term

Even the mysterious-sounding “black moon” cannot be seen in the sky. The term is not yet very widespread and does not come from astronomy. That’s why there is no clear definition of what a “black moon” actually is. This can mean four different phenomena:

• Seasonal “black moon”: The third of four new moons in an astronomical season is sometimes referred to as this. Most seasons only have three new moons.
• Month without a new moon: This phenomenon can only occur in February because the month has fewer days than a complete lunar cycle, which lasts about 29.5 days. If there is a new moon at the end of January, it may happen that there will be no new moon in the sky in February.
• Month without a full moon: Even a month without a full moon is only possible in February. However, there are then two full moons in January and March – i.e. two “blue moons”.
• Monthly “black moon”: The term refers to the second new moon in a month in which there are two new moons.

“Black moon” in December 2024: Second new moon of the month

There will be a monthly “black moon” in December 2024: First, there will be an invisible new moon in the sky on December 1st, followed by the full moon on December 15th. Because December consists of 31 days, there is room for another new moon in the month: it will occur on December 30, 2024, but cannot be seen in the sky either.

To put it simply, one can say that the definition of the “black moon” is similar to the “blue moon”. This usually means the second full moon within a month. However, the third full moon in a season with four full moons can also be called this way. In contrast to the black moon, which actually appears “black”, the “blue moon” is not blue. The term comes from the English saying “once in a blue moon” (roughly “every jubilee year”) and indicates that the “blue moon” does not occur often. (tab)