- Jan 6 Astronomers at University of California see 1st sight of birth of a galaxy
- Jun 8 New Zealand's Labour government legislates against nuclear weapons and nuclear powered vessels in NZ. Only nation to legislate against nuclear power.
- Jun 11 Margaret Thatcher is 1st British Prime Minister in 160 years to win a third consecutive term
- Oct 19 Black Monday: Dow Jones stock index falls 508.32 points (22%), 4½ times the previous daily record
- Jan 22 Pennsylvania politician R. Budd Dwyer shoots and kills himself at a press conference on live national television, leading to debates on boundaries in journalism
- Apr 5 Fox TV network premieres showing "Married With Children" and "The Tracey Ullman Show"
- May 30 North American Philips Company unveils compact disc video
- Jun 5 "Nightline" presents its 1st "Town Meeting" the subject is AIDS & the show runs until 3:47 AM
- Jun 6 French Open Women's Tennis: 17 year old German Steffi Graf beats World #1 Martina Navratilova 6-4, 4-6, 8-6; Graf's first Grand Slam victory
- Jun 20 1st Rugby World Cup: New Zealand beats France 29-9 in Auckland
- Aug 14 Oakland's Mark McGwire sets rookie HR record at 39, en route to 49
- Oct 31 American jockey Chris Antley becomes first rider to win 9 races in a day (4 at Aqueduct / 5 at The Meadowlands)
1st military use of trained dolphins (US Navy in Persian Gulf)
On October 13, 1987