The sight you’ll want to check out in the night sky Friday is something you’ll have a hard time seeing at all. A black moon is set to rise. Despite the spooky name and what some people might tell you, it’s literally not the end of the world.

A “black moon” is just a term used for a second new moon in a single month. A new moon is when the sun illuminates the side of the moon facing away from us and the moon is on the sunny side of the earth anyway.

It’s basically just the opposite of a “blue moon,” which is the term for the second full moon in a month. It’s rare, but not super rare. The last time it happened was in March 2014.

That’s it. It’s not the end of the world, as some headlines might suggest, just the interesting intersection of planetary geometry and the Gregorian calendar most of the world uses.

The phases of the moon


There are end times prophecies that mention the moon turning to blood or turning black, but these are probably not referring to the informal names used to describe regular phases of the moon. (They seem to go perpetually unrealized, anyway.)

Now if you’re into really old-school gods and goddesses, you might note any new moon is associated with some interesting or even creepy (depending on your perspective) characters like Hecate. She’s the ancient Greek goddess of crossroads, magic, ghosts and the dead who is also still a part of some Wiccan traditions.

But we’ve been having new moons about every four weeks for billions of years and the concept of a black moon is dependent on a calendar that’s been in use less than 500 years, much more recently than when Jesus and the authors of the Bible or Hecate were in their prime.

In fact, the black moon here in the Americas probably isn’t the eeriest of celestial events going down this season. Because this week’s new moon will technically begin on the first day of October for those in much of the Eastern Hemisphere, they’ll experience a black moon at the end of October, just in time for Halloween.

Correction, 2:50 p.m. PT: This story initially misstated when the last black moon rose. It was in March 2014.


A 'black moon' is rising, but Earth will be just fine – CNET