Jewish culture and many Jewish scientists had a significant role in the project. The theoretical physicist Robert Oppenheimer, often considered as the ""father of the atomic bomb"", was chosen to direct the Manhattan Project at Los Alamos National Laboratory in 1942. The physicist Leó Szilárd, that conceived the nuclear chain reaction; Edward Teller, ""the father of the hydrogen bomb"" and Stanislaw Ulam; Eugene Wigner contributed to theory of Atomic nucleus and Elementary particle; Hans Bethe whose work included Stellar nucleosynthesis and was head of the Theoretical Division at the secret Los Alamos laboratory; Richard Feynman, Niels Bohr, Victor Weisskopf and Joseph Rotblat.
Soviet atomic bomb project (including those now in Kazakhstan). The uranium for the Soviet nuclear weapons program came from mine production in the following countries, RDS-1, the first Soviet atomic test was internally code-named "First Lightning" ("Первая молния", or Pervaya Molniya) August 29, 1949, and was code-named by the Americans as "Joe 1". The design was very similar to the first US "Fat Man" plutonium bomb, using a TNT/hexogen implosion lens design. On September 24, 1951, the 38.3 kiloton device RDS-2 was tested based on a tritium "boosted" uranium implosion device with a levitated core. This test was code named "Joe 2" by the