A rare phenomenon: Blue Moon is all set to grace the sky on October 31

October 2020 is literally a 'once in a blue moon' thing and the reason is blue moon, a rare phenomenon . October 1 saw a full moon and the next full moon falls on October 31.
When there are two full moons in a calendar month, the second full moon is called the Blue Moon.
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The usual monthly lunar phenomenon is that every month has one full moon and a new moon. However, there are unusual occasions when the same month gets two full moons.
The last ‘blue moon’ in a month with 30 days was on June 30, 2007, and the next will be on September 30, 2050.
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“Duration of a lunar month is 29.531 days or 29 days, 12 hours, 44 minutes and 38 seconds. Therefore, to have two full moons in a month, the first full moon should take place on 1st or 2nd of the month,” Arvind Paranjpaye, director of Nehru Planetarium, Mumbai explained to PTI.
This extra time accumulates over the months. After about 30 months there will be one extra full moon in the year, Paranjpaye said.
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As per PTI report, there were two Blue Moons in 2018. The first one was on January 31 and the second Blue Moon followed on March 31.
The next Blue Moon will be on August 31, 2023, Paranjpaye added.
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The blue in the 'blue moon' has nothing to do with colour. It is an infrequent phenomenon involving appearance of an additional full moon within a given period.
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