On July 31st a rare phenomenon could be seen all around the world — a Blue Moon.
A Blue Moon, while not exactly blue in colour, is the term for the second full moon to occur in a calendar month.
The reason for this anomaly is explained by Columbia University professor of Astrology James Applegate: “The fact that our months are about a day longer than the time between full moons means that if the 1st or 2nd (for a 31-day month) is a full moon, then we get a second full moon (the blue moon) in the same month.”
This rarity won’t be seen again until January 31, 2018, but skygazers around the world took plenty of photos of last night’s Blue Moon in case you missed out.
A full moon, known as the Blue Moon, is seen next to the Statue of Liberty in New York July 31, 2015.
A blue moon rises behind Brooklyn seen from Liberty State Park in Jersey City, N.J., Friday, July 31, 2015.
A full moon rises behind the Alvorada Palace, designed by Brazilian architect Oscar Niemeyer, in Brasilia, Brazil, Friday, July 31, 2015.
Fireworks explode as the blue moon rises in the distance at Worlds of Fun amusement park Friday, July 31, 2015, in Kansas City, Mo.
A full moon, known as the Blue Moon is seen over Loosely Row, near Princes Risborough, southeast England, July 31, 2015.
A cyclist rides his mountain bike as a full moon, known as the Blue Moon, rises in a park in Rome, Italy, July 31, 2015.
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