 He joined the Project Plowshare efforts in 1957 after attending a meeting on the topic arranged by Edward Teller.There are two parts to a typical hydrogen bomb, a plutonium-based atomic bomb known as the "primary", and a cylindrical arrangement of fusion fuels known as the "secondary".The primary releases significant amounts of x-rays, which are trapped within the bomb casing and heat and compress the secondary until it undergoes fusion.