July 16: First nuclear test: The United States successfully detonates the first atomic bomb, codenamed "Trinity," at the Alamogordo Bombing Range in New Mexico. This marks the beginning of the nuclear age.
August 6: Atomic bomb dropped on Hiroshima: The US drops an atomic bomb named "Little Boy" on the Japanese city of Hiroshima. The bomb instantly kills an estimated 80,000 people and causes widespread devastation.
August 9: Atomic bomb dropped on Nagasaki: The US drops a second atomic bomb named "Fat Man" on the city of Nagasaki. Approximately 40,000 people are killed immediately, and thousands more die in the aftermath due to radiation exposure and related illnesses.
1949:
August 29: First soviet atomic bomb test: The Soviet Union successfully tests its first atomic bomb, code named "RDS-1," at the Semipalatinsk Test Site in Kazakhstan. This event ends the US monopoly on nuclear weapons and begins the era of nuclear arms race between the two superpowers.
1957:
October 4: Launch of Sputnik: The Soviet Union successfully launches the first artificial satellite, Sputnik, into orbit around the Earth. This achievement demonstrates the Soviet Union's advances in space technology and escalates the Cold War tensions as well as raising concerns about the potential use of missiles to deliver nuclear weapons.