The hydrogen bomb, or thermonuclear bomb, is the most destructive weapon yet developed by humankind. The hydrogen bomb derives its massive destructive energy from the fusion (joining together) of hydrogen isotopes. Research and development of the first hydrogen bomb was conducted at the Los Alamos National Laboratory, N.M. from 1949-51 under the direction of Edward Teller (U.S.). The United States exploded the first hydrogen bomb on the Pacific atoll of Eniwetok on November 1, 1952 (October 31, 1952 EST). In August 1953 the USSR detonated its first hydrogen bomb. (Inventions and Discoveries)