There will be a “once in a blue moon” lunar occurrence on Friday.
A second full moon appearance in this month will occur on July 31; and while it is called a Blue Moon, it has got no connection with the color of the Earth’s only natural satellite.
A full moon appears once a month, and so in a year we see 12 full moons. However, because of the lunar month and the calendar not being in sync with one other, this rare lunar event occurs once every two or three years.
A lunar or synodic month – which lasts from one full moon occurrence to the next – lasts for 29.530589 days, while each month (except February) has either 30 or 31 days. This difference amalgamates over a period of two or three years, causing two full moons in a particular month, as reported by CBS News.
Color Of Blue Moon Isn’t Really Blue
The color of the moon during this phenomenon is actually a gray or silver like. However, when a full moon does appear blue, it is due to the presence of smoke or dust particles in the atmosphere.
According to CNN, one such occurrence was in 1883 when the Indonesian volcano Krakatoa spit a large volume of ash into the atmosphere, causing the moon to appear a cerulean tinge for years.
A Blue Moon will not appear again until January 2018.
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