Black & Blue
Did you know that? I didn't. Neither did my Mac calendar program BusyCal. Or LunaSolCal, an iOS app that I use to calculate the times of sunrises, sunsets, equinoxes, solstices, full moons, and new moons.
Apparently the phrase black moon originated in 2008.
But just like a blue moon, a black moon is a calendar artifact. It's not a natural wonder, well, no more than normal.
Let me explain. With LunaSolCal, my iPod Touch can predict the local sunrise and sunsets. There is an alarm that goes off for each. But the sunrise and sunset happens despite my iPod Touch, not because of it. That cute electronic rooster crow doesn't bring the sunrise.
Many pagans use specific calendar dates for the sabbats, but that is not necessarily when the equinoxes, solstices, and cross quarter days actually happen. These events are not linked to the calendar, the calendar is linked to them.
Or at least it used to be.
So when we saw that the black moon is the second new moon in a month, it's still a new moon. Or as I prefer, a dark moon. Just as a blue moon is still a full moon. Or bright moon.
Blue and black are because of the mismatch between the calendar and celestial events. There is no special merit above other bright and dark moons.
It's the calendar that has got it wrong.
ETA 15Oct2016: Here's another example.
❝Many people enjoy the supermoon because it can provide a strange, bright power over the evening. The proximity makes the moon’s light far brighter, and can make the rock itself much easier to see.
But this month it will be even more easy to spot than usual. That’s because it combines with the hunter’s moon.
The hunter’s moon gets its name partly from the time in the year that it comes. Every moon through the months is given its own name – and the hunter’s moon comes the month after the harvest moon, which itself is the full moon closest to the autumn equinox.❞
Now the supermoon, that's a thing. It can be measured.
The hunter's moon, that is an calendar artifact.
The fact the two coincide in 2016 has no additional meaning.