The sky on the night between October 31 and November 1 will be illuminated by the so-called "blue moon", ie the second full moon in a period of 30 days.
This is the first case since March 2018, but also the first full moon to appear on October 31 in all time zones since 1944.
The phenomenon of the Blue Moon does not necessarily mean that the moon is blue and it is a rare occurrence.
The term "blue moon" itself appeared in England in the 16th century, and probably earlier, in the form of Belewe Moon, which means "traitor" (in modern language: betrayer), because such an additional full moon at some time confused farmers. Over time, "belewe" became "blue". This, therefore, has nothing to do with blue or the optical phenomenon in which the Moon appears bluish due to the large amount of suspended particles in the atmosphere, which selectively remove visible light of longer wavelength.
This is fantastic astronomic phenomena.. Thank you so much!