| 1918 | Leon Trotsky began establishing the Red Army in the Soviet Union. |
| 1921 | Albert Einstein proposed that the universe could be measured. It started a debate in the scientific world. |
| 1935 | Iceland became the first country to legalize abortion. |
| 1986 | The space shuttle Challenger disintegrated 73 seconds after launch: seven astronauts died. It was claimed that the error was caused by leakage in solid fuel engines. |
| 1988 | THY banned smoking on domestic flights. |
| 2002 | A Boeing 727-100 passenger plane belonging to Ecuadorian Airlines crashed into the Andes mountains in southern Colombia: 92 people died. |
| 2006 | The roof of an exhibition palace in Katowice, Poland, collapsed under the weight of accumulated snow: 62 people died and 140 people were injured. |