1923 – Bulgaria’s government was overthrown by the military.
1931 – Robert H. Goddard patented a rocket-fueled aircraft design.
1940 – Norway surrendered to the Nazis during World War II.
1945 – Japanese Premier Kantaro Suzuki declared that Japan would fight to the last rather than accept unconditional surrender.
1959 – The first ballistic missile carrying submarine, the USS George Washington, was launched.
1986 – The Rogers Commission released a report on the Challenger disaster. The report explained that the spacecraft blew up as a result of a failure in a solid rocket booster joint.
1999 – NATO and Yugoslavia signed a peace agreement over Kosovo.
2000 – Canada and the United States signed a border security agreement. The agreement called for the establishment of a border-enforcement team.
2011 – The world’s first artificial organ transplant was performed. It was an artificial windpipe coated with stem cells.