Most people have heard the phrase, “Once in a blue moon” before, and understand that it refers to something that does not happen very often. Of course, the phrase comes from the actual phenomena of a blue moon.

Blue moons have two definitions. The first one is a ‘seasonal blue moon’ which is identified as the third full moon in a season where four full moons occur. For those who aren’t aware, most seasons only have three full moons.

The second definition of a blue moon is the second blue moon that occurs during a calendar month. Both of these are pretty rare, occurring about every 29 months and 33 months respectively.

So, what is a black moon?

Well, if a blue moon is when these events take place with a full moon, a black moon is when they take place with a new moon.

Like the blue moon, black moons have the same two options for definitions. Unlike blue moons, however, you can’t really see black moons.

This is because all new moons occur when the moon is located between the Earth and the Sun. This means none of it is illuminated for people on the part of the Earth experiencing the new moon.

So, why should anyone care about a black moon? Well, just like any new moon, black moons are great times to do stargazing. Since the moon does not reflect light toward the Earth during these times, the sky is significantly darker. This makes it easier for people to see stars, planets, meteors, and other phenomena in the sky.

The next black moon will occur on August 23, 2025 so get ready. After that, it won’t happen again until August 31st, 2027.

I’ve never even heard of a black moon.

If you thought that was interesting, you might like to read about why we should be worried about the leak in the bottom of the ocean.