Iran's leaders are threatening to breach a 2015 agreement that froze their country's nuclear program. What is uranium enrichment, and what would it mean for Iran's ability to build nuclear weapons?
Feb. 28 marks the 75th anniversary of Operation Gunnerside. A stealthy group of skiing commandos took out a crucial Nazi facility and stopped Hitler from getting the atomic bomb.
By figuring out fission, physicists were able to split uranium atoms and release massive amounts of energy. This Manhattan Project work paved the way both for atomic bombs and nuclear power reactors.