X-10 Graphite Reactor Belgium. Financed through the Belgian uranium export tax, and built with the help of British experts, the 4 MW research reactor went critical for the first time on May 11, 1956. It is used for scientific purposes, such as neutron activation analysis, neutron physics experiments, calibration of nuclear measurement devices and the production of neutron transmutation doped silicon. X-10 Graphite Reactor The X-10 Graphite Reactor at Oak Ridge National Laboratory in Oak Ridge, Tennessee, formerly known as the Clinton Pile and X-10 Pile, was the world's second artificial nuclear reactor (after Enrico Fermi's Chicago Pile-1), and the first designed and
Fermi paradox Fermi paradox The Fermi paradox, or Fermi's paradox, named after physicist Enrico Fermi, is the apparent contradiction between the lack of evidence and high probability estimates for the existence of extraterrestrial civilizations. The basic points of the argument, made by physicists Enrico Fermi (1901–1954) and Michael H. Hart (born 1932), are: According to this line of reasoning, the Earth should have already been visited by extraterrestrial aliens. In an informal conversation, Fermi noted no convincing evidence of this, leading him to ask, "Where is everybody?" There have been many attempts to explain the Fermi paradox, primarily either suggesting that intelligent