The discovery of spontaneous fission in reactor-bred plutonium due to contamination by plutonium-240 led Wigner to propose switching to breeding uranium-233 from thorium , but the challenge was met by the Los Alamos Laboratory developing an implosion-type nuclear weapon design . In October 1944 , Creutz moved to Los Alamos , where he became a group leader responsible for explosive lens design verification and preliminary testing . Difficulties encountered in testing the lenses led to the construction of a special test area in Pajarito Canyon , and Creutz became responsible for testing there . As part of the preparation for the Trinity nuclear test , Creutz conducted a test detonation at Pajarito Canyon without nuclear material . This test brought bad news ; it seemed to indicate that the Trinity test would fail . Hans Bethe worked through the night to assess the results , and was able to report that the results were consistent with a perfect explosion
Trinity nuclear test
Trinity (nuclear test)
Edward Creutz