In The Night Sky Friday: Rare Black Moon

DETROIT (CBS Detroit) - Usually we say "look up!" ... but you might not want to bother this time.

While it sounds pretty cool and is an uncommon occurrence, scientists say star-gazers won't be able to see the "black moon" set to rise in the night sky at 8:11 p.m. EST this Friday, Sept. 30.

Mike Narlock, Head of Astronomy at Cranbrook Institute of Science, explains a black moon means it's the second new moon in a month — and you can't see a new moon.

"A black moon is when you have two new moons in a calendar month — so that means the two nighttime sides of the moon are facing us," Narlock said. "It's like the dark side of the moon....(the name) is related to the fact that you can't actually see it."

While the invisible black moon won't get as much love as a bright-shining blue moon or a meteor shower, it's still notable.

According to ScienceAlert.com, while some say a black moon occurs about once every 19 years, when the month of February skips a full moon, the most common definition for a black moon is that it's the second new moon in a calendar month (as Narlock said). This means this Friday's event is the second time in September that the moon will be entirely invisible in the night sky — for those in the Western Hemisphere, including Michiganders.

"There's a pattern to it all, but there's no planning an event around it," Narlock said, adding, however, those who have a high-powered telescope may be able to catch a special moment a couple of days when just a tiny silver sliver of light can is visible.

"It's really quiet beautiful," he said.

So, what about something we CAN see? Narlock said, unfortunately, there won't be another blue moon (which is the second full moon in a month) until May of 2019.

There are a couple of cool meteor showers coming up next month, though. These include the Draconids, in early October, and the Orionids — notable, Narlock says, as they're actually particles from Halley's Comet — set to peak on Oct. 21.