Ever heard the saying, “once in a Blue Moon?” Be sure to look up in the sky on Friday. Most of the world will be able to witness a Blue Moon, which is a fairly rare occurrence that doesn’t have anything to do with color!
Usually, Earth experiences 12 moons, one in each month, CBS reports. But in some years, like in 2015, Earth has 13 moons, and that extra moon gets the title Blue Moon. Blue Moons happen every three years, according to the National Oceanic and Atmospheric Administration.
Wait, 13 moons? Were you thinking we only had one? That’s not what I mean. Here is a chronological list of full-moon dates for 2015: Jan. 5, Feb. 3, March 5, April 4, May 4, June 2, July 2, July 31, Aug. 29, Sept. 28, Oct. 27, Nov. 25 and Dec. 25. In 2016, the first full moon will appear on Jan. 23 and every other month will contain one full moon.
Make sense? OK. Moving on.
The saying “once in a Blue Moon” serves true in describing something uncommon, but it does not serve true when speaking of the color. The moon will actually be a gray or silver color.
Like I said, the saying describes rare occurrences, but it has also been used in the Maine Farmers’ Almanac to define the third full moon in a season with four full moons.
In 1946, a magazine got it wrong and described a Blue Moon as the second full moon in a calendar month, according to CBS. So that is what is commonly referred to as a Blue Moon.
The full moon appears to last for an entire night, but like many events in our sky, it is an illusion. The event is really instantaneous–when the Moon and Earth nearly hit a straight line–and it occurs at the same time everywhere in the world.
The last Blue Moon was observed in August 2012 and the next will appear in January 2018.
The Delta Aquarid meteor shower is also starring in our sky this week, with its peak estimated for July 27-30, CBS local reports. But since the full moon will be hogging the spotlight, it may be hard to see a shooting star.
Go find a clear view of the sky this week!