From a US perpetual calendar: September 21, 1989 was on Thursday.
The day of the week for September 21, 1978 was a Thursday.
September 21st, 1930 fell on a Sunday.
September 21st, 1947 fell on a Sunday.
Wednesday
August 21st, 1989 fell on a Monday.
September 21, 1995, was a Thursday.
23 September 1989 was a Saturday.
September 8 1989 was on a Friday.
September 25 1989 was on a Monday.
September 2nd, 1989 was a Saturday.
September 2, 1989, was a Saturday.
September 9 1989 was a Saturday.