It was a Monday.
September 20 in 1969 was a Saturday.
July 20, 1969 was a Sunday
January 20 1949 was on a Thursday.
January 20, 2009 was on a Tuesday.
January 20 1933 was a Friday.
January 20 1967 was a Friday.
January 20 2010 was a Wednesday.
January 20, 1987 was a Tuesday.
January 20, 1957 was a Sunday.
20 January 2004 was a Tuesday.
20 January 1980 was a Sunday.