Enrico Fermi of his life, Fermi questioned his faith in society at large to make wise choices about nuclear technology. He said: Fermi underwent an exploratory operation in Billings Memorial Hospital on 9 October 1954, after which he returned home. 50 days later, Fermi died at age 53 of stomach cancer in his home in Chicago. His memorial service was held at the University of Chicago chapel, where colleagues, Samuel K. Allison, Emilio Segrè, and Herbert L. Anderson spoke, mourning the loss of one of the world's "most brilliant and productive physicists." His body was interred at Oak Woods Cemetery. Fermi received
Nuclear reactor new type of reactor using uranium came from the discovery by Lise Meitner, Fritz Strassmann and Otto Hahn in 1938 that bombardment of uranium with neutrons (provided by an alpha-on-beryllium fusion reaction, a "neutron howitzer") produced a barium residue, which they reasoned was created by the fissioning of the uranium nuclei. Subsequent studies in early 1939 (one of them by Szilárd and Fermi) revealed that several neutrons were also released during the fissioning, making available the opportunity for the nuclear chain reaction that Szilárd had envisioned six years previously. On 2 August 1939 Albert Einstein signed a letter to President