The correct order of events (with dates and notes following):
- The Soviet Union’s spies gathered information about the US Manhattan project
- The United States created three bombs as a result of the Manhattan Project.
- The Soviet Union detonated its first atomic bomb.
- The United States detonated the first thermonuclear or hydrogen bomb.
Details:
- Soviet espionage concerning the Manhattan Project occurred all the way along the line during the project, from 1940-1945.
- The first bomb, called "Gadget," was detonated as a test model in July, 1945. The "Little Boy" and "Fat Man" bombs were dropped on Hiroshima and Nagasaki in August, 1945.
- The Soviet Union tested its first atomic bomb in 1949.
- The US achieved development of a hydrogen bomb in 1952