Which specific lunar timing pattern defines a Calendrical Black Moon?

Answer

A single calendar month containing two New Moons.

The Calendrical Black Moon happens because the lunar cycle (about 29.5 days) is slightly shorter than most calendar months, allowing an extra New Moon to fall within one month.

Which specific lunar timing pattern defines a Calendrical Black Moon?

#Videos

A Black Moon Is Coming — See Why It's So Rare! - YouTube

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