20 January

January 20 is the 20th day of the year in the Gregorian calendar. There are 345 days remaining until the end of the year (346 in leap years). This date is slightly more likely to fall on a Wednesday, Friday or Sunday (58 in 400 years each) than on Monday or Tuesday (57), and slightly less likely to occur on a Thursday or Saturday (56).

In the ancient astronomy, it is the cusp day between Capricorn and Aquarius.

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Wikipedia