'Super blue moon' will not appear blue in colour'!

So, why the name?

The forthcoming full Moon, which will emerge on Wednesday, will be a super Moon, a blue moon, and Rakhi Purnima or Raksha Bandhan, the Hindu festival honoring sibling ties. Contrary to its nickname, the "Blue Moon," the celestial body won't truly seem blue. 

The term "Blue Moon" was coined by Sky & Telescope magazine in 1946 and refers to the second full Moon in a calendar month.

The term "Blue Moon" has been used to refer to the third full Moon in a season with four Moons since at least the 1500s.

The full Moon in August 2024 will be the Blue Moon, according to this definition. According to NASA's website, neither of these definitions has anything to do with the Moon's color.

A Real blue Moon:

Blue moons, which lasted for several days in the 19th century, were caused by the ash from the Indonesian volcano Krakatoa.

Light from the sun travels in waves, and different colors of light have various physical characteristics, such as wavelengths. The colors we perceive are a result of sunlight being dispersed by the atmosphere. 

According to NASA, some of the ash clouds from Krakatoa's eruption in 1883 had particles that were 1 micron (one millionth of a meter) broad, the ideal size to substantially scatter red light while allowing other colors to get through. This caused the moonbeams to sometimes seem green and sometimes blue.

In 1983, following the El Chichon volcano eruption in Mexico, a second incident of a similar nature took place.