December 21

December 21 is the 355th day of the year (356th in leap years) in the Gregorian calendar. There are 10 days remaining until the end of the year. This date is slightly more likely to fall on a Monday, Wednesday or Friday (58 in 400 years each) than on Saturday or Sunday (57), and slightly less likely to occur on a Tuesday or Thursday (56).

In the Northern Hemisphere, December 21st is usually the shortest day of the year and is sometimes regarded as the first day of winter. In the Southern Hemisphere, December 21st is usually the longest day of the year and occurs during the southern summer.

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