Double full moon in a month - Rare occurrence in October 2020
Very rarely does it happen that we have the full moon twice in a month. Namely only if the first full moon falls on the 1st and the second full moon exactly on the 31st of a month. This is exactly the case in October 2020.
The second full moon is even a blue moon.
In the Cosirex calendar you can recognize and understand this lunar-astronomical event:
Have fun with the full moon doublet!