'Blue Moon' Tuesday Night

Another definition of a visible "blue moon" from the Total Lunar Eclipse of 2009 December.
(Image Source: Wikipedia.org )

By Glenn A. Walsh
Reporting for SpaceWatchtower

The August Full Moon will occur on Tuesday Evening, 2013 August 20 at 9:45 p.m. EDT (August 21, 01:45 Coordinated Universal Time). And, this is actually considered a "Blue Moon."

While most people consider a "Blue Moon" to be the second Full Moon in a calendar month, the more classical definition of a "Blue Moon" is the third Full Moon in a calendar season which has four full moons. Most calendar seasons have three full moons, for the three months per season.

However, this year (2013) the Summer season actually has four full moons: June 23, July 22, August 20, and September 19. Hence, the August Full Moon is considered a "Blue Moon," by the classical definition. The previous "Blue Moon," by the classical definition, was on 2010 November 21. The last "Blue Moon," by the new and more popular definition of the second Full Moon in one calendar month, was on 2012 August 31.

The third Full Moon in a season with four full moons was called a "Blue Moon," so that the nicknames normally given to the three full moons of a season by the Native Americans, and later adopted by farmers who immigrated to America from Europe, could remain consistent for that particular season. In the 19th century, the Maine Farmers' Almanac started listing "Blue Moons," as an aid to farmers.

In March of 1946, Sky and Telescope Magazine misinterpreted the classical "Blue Moon" definition, by interpreting the 1937 Maine Farmers' Almanac as promoting eleven months with one full moon and one month with two full moons. Hence, started the more popularly-known definition of a "Blue Moon" being the second Full Moon in a calendar month. The daily radio program, StarDate, found the 1946 misinterpretation and popularized it in their broadcast of 1980 January 31.

Is one "Blue Moon" definition better than another? Folklorist Phillip Hiscock of Memorial University of Newfoundland wrote of the new definition in his article "Folklore of the 'Blue Moon'," for the 1993 December issue of the International Planetarium Society's quarterly journal Planetarian: "Old folklore it is not, but real folklore it is."

Native Americans had several names for the Full Moon of August: Sturgeon Moon, Red Moon, Grain Moon, Green Corn Moon, or simply Corn Moon. Of course, these referred to the time of year when harvesting grain or corn was beginning, the best time to catch sturgeon, or the red appearance of the Moon as it rises in the haze of late Summer.

In Earth's Southern Hemisphere which is in the middle of the Winter season, the Full Moon of August is known by the names Snow Moon, Storm Moon, Hunger Moon, and Wolf Moon.

More on a "Blue Moon":
Link 1 >>> http://earthsky.org/space/when-is-the-next-blue-moon
Link 2 >>> http://en.wikipedia.org/wiki/Blue_moon

More on the Full Moon: Link >>> http://en.wikipedia.org/wiki/Full_moon

More on Full Moon Names:
Link 1 >>> http://earthsky.org/astronomy-essentials/full-moon-names
Link 2 >>> http://www.farmersalmanac.com/full-moon-names/
Link 3 >>> http://en.wikipedia.org/wiki/Farmers%27_Almanac_full_moon_names#Farmers.27_Almanacs

Source: Glenn A. Walsh, Reporting for SpaceWatchtower, a project of Friends of the Zeiss.

Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
About the SpaceWatchtower Editor/Author: < http://buhlplanetarium.tripod.com/#GAW >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
< http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* Civil War Museum of Andrew Carnegie Free Library:
  < http://garespypost.tripod.com >
* Duquesne Incline cable-car railway, Pittsburgh:
  < http://inclinedplane.tripod.com >
* Public Transit:
  < http://andrewcarnegie2.tripod.com/transit >