The next Blue Moon is July 31, 2015, reported USA Today.

The name Blue Moon is used to describe the second full moon of a calendar month. There was a full moon on July 2, 2015. So, the full moon on July 31 will be called a Blue Moon.

The phenomenon occurs once every two to three years. The last Blue Moon happened on August 31, 2012.

The full moon on July 31 is also expected to affect the impact of the Delta Aquarid meteor shower since the bright light of the earth's satellite will contend with the meteor shower. 

According to the baynet.com, the concept of the Blue Moon as the second full moon in a month originated from an article called "Once in a Blue Moon" by James Hugh Pruett that was contained in the March 1946 issue of Sky and Telescope magazine.

The blue moon occurs only when the first full moon happens in the first few days of the month. This phenomenon occurs once in every two to three years, so 'Blue Moons' occur once in 2-3 years.

However, the blue moon is not usually blue in color. It's rare to see a blue-colored moon and only unusual sky conditions, such as certain-sized particles of dust or smoke can create a blue moon.