Generally, a month only has 1 Full moon. However, once every couple of years, a month will have 2 Full moons. This occurrence is called a "Blue Moon". This usage results from a misinterpretation of the traditional definition of blue moon in the March 1946 issue of Sky and Telescope.
A blue moon occurs only every two or three years, and the term blue moon is used colloquially to mean a rare event, as in the phrase "once in a blue moon".
The apparent colour of the moon, at any time of the year, can be affected by atmospheric circumstances. Volcanic eruptions and exceptionally large fires can leave particles in the atmosphere which give the sky, and thus the Moon, a tinge of blue (or other colours).
Read more about Blue Moon: Origin, Early English and Christian Usage, Maine Farmers' Almanac Blue Moons, Visibly Blue Moon, Blue Moons Between 2009 and 2021, Popular Culture
Famous quotes containing the words blue and/or moon:
“...the shiny-cheeked merchant bankers from London with eighties striped blue ties and white collars and double-barreled names and double chins and double-breasted suits, who said “ears” when they meant “yes” and “hice” when they meant “house” and “school” when they meant “Eton”...”
—John le Carré (b. 1931)
“The moon is door. It is a face in its own right,
White as a knuckle and terribly upset.
It drags the sea after it like a dark crime; it is quiet
With the O-gape of complete despair.”
—Sylvia Plath (1932–1963)