This sculpture by Henry Moore marks the site at the University of Chicago where Metallurgical Laboratory scientists created the world's first self-sustaining nuclear chain reaction.

The Metallurgical Laboratory or "Met Lab" at the University of Chicago was part of the World War II–era Manhattan Project, created by the United States to develop an atomic bomb. Image File history File links Henry_Moore_Nuclear_Energy. ... Image File history File links Henry_Moore_Nuclear_Energy. ... Reclining Figure (1951) outside the Fitzwilliam Museum, Cambridge, is characteristic of Moores sculptures, with an abstract female figure intercut with voids. ... The University of Chicago is a private university located principally in the Hyde Park neighborhood of Chicago, Illinois. ... The University of Chicago is a private university located principally in the Hyde Park neighborhood of Chicago, Illinois. ... This article is becoming very long. ... The Manhattan Project resulted in the development of the first nuclear weapons, and the first-ever nuclear detonation at the Trinity test of July 16, 1945. ... The mushroom cloud of the atomic bombing of Nagasaki, Japan, 1945, rose some 18 kilometers (11 mi) above the hypocenter. ...

History

In July 1939, at the urging of physicists Eugene Wigner and Leó Szilárd, Albert Einstein sent a letter to President Franklin Delano Roosevelt explaining the military potential of nuclear fission and calling for the United States to develop atomic weapons before Nazi Germany did. 1939 (MCMXXXIX) was a common year starting on Sunday (link will take you to calendar). ... Physicists working in a government lab A physicist is a scientist who is a practitioner of physics. ... Eugene Wigner Eugene Paul Wigner (Hungarian Wigner Pál JenÅ‘) (November 17, 1902 – January 1, 1995) was a Hungarian physicist and mathematician who received the Nobel Prize in Physics in 1963 for his contributions to the theory of the atomic nucleus and the elementary particles, particularly through the discovery and... Leó Szilárd (February 11, 1898 – May 30, 1964) was a Hungarian-American physicist who conceived the nuclear chain reaction and worked on the Manhattan Project. ... Albert Einstein, photographed in 1947 by Oren J. Turner. ... Franklin Delano Roosevelt (January 30, 1882–April 12, 1945), 32nd President of the United States, the longest-serving holder of the office and the only man to be elected President more than twice, was one of the central figures of 20th century history. ... An induced nuclear fission event. ... Nazi Germany, or the Third Reich, commonly refers to Germany in the years 1933–1945, when it was under the firm control of the totalitarian and fascist ideology of the Nazi Party, with the Führer Adolf Hitler as dictator. ...

In response, Roosevelt appointed a committee to direct the research. Early funding was meager, but in 1940, scientists at Columbia University and the University of California were able to demonstrate the weapons potential of the isotope uranium-235 and the newly-discovered element plutonium. 1940 (MCMXL) was a leap year starting on Monday (the link is to a full 1940 calendar). ... Columbia University is a private university whose main campus lies in the Morningside Heights neighborhood of the Borough of Manhattan in New York City. ... The University of California (UC) is a public university system in the state of California. ... Isotopes are forms of an element, therefore their nuclei have the same atomic number — the number of protons in the nucleus — but different mass numbers because they contain different numbers of neutrons. ... Uranium-235 is an isotope of uranium that differs from the elements other common isotope, uranium-238, by its ability to cause a rapidly expanding fission chain reaction. ... A chemical element, often called simply element, is a chemical substance that cannot be decomposed or transformed into other chemical substances by ordinary chemical methods. ... General Name, Symbol, Number plutonium, Pu, 94 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery white Atomic mass (244) g/mol Electron configuration [Rn] 5f6 7s2 Electrons per shell 2, 8, 18, 32, 24, 8, 2 Physical properties Phase solid Density (near r. ...

Immediately after the Japanese attack on Pearl Harbor on December 7, 1941, Nobel Prize laureate Arthur H. Compton quickly gained support for consolidating plutonium research at Chicago and for an ambitious schedule that called for producing the first atomic bomb in January 1945, a goal that was missed by only six months. Satellite image of Pearl Harbor. ... December 7 is the 341st day (342nd in leap years) of the year in the Gregorian calendar. ... For the movie, see 1941 (film) 1941 (MCMXLI) was a common year starting on Wednesday (the link is to a full 1941 calendar). ... Nobel prize medal. ... Arthur Holly Compton (September 10, 1892 – March 15, 1962) won the Nobel Prize in Physics (1927) for discovery of the effect named after him. ... 1945 (MCMVL) was a common year starting on Monday (the link is to a full 1945 calendar). ...

"Metallurgical Laboratory" was the "cover" name given to Compton's facility. Its objectives were to produce chain-reacting "piles" of uranium to convert to plutonium, find ways to separate the plutonium from the uranium and to design a bomb. A chain reaction is a sequence of reactions where a reactive product or by-product causes additional reactions. ...

In August 1942, a team of scientists under Glenn T. Seaborg isolated the first weighable amount of plutonium from uranium irradiated in cyclotrons. Meanwhile, work continued under the renowned Italian physicist Enrico Fermi to build uranium and graphite piles that could be brought to critical mass in a controlled, self-sustaining nuclear reaction. 1942 (MCMXLII) was a common year starting on Thursday (the link is to a full 1942 calendar). ... Glenn T. Seaborg Glenn Theodore Seaborg (April 19, 1912 – February 25, 1999) was an American chemist prominent in the discovery and isolation of ten transuranic elements including plutonium, americium, curium, berkelium, californium, einsteinium, fermium, mendelevium, nobelium and seaborgium, which was named in his honor. ... Irradiation is the process whereby an item is exposed to radiation. ... A pair of Dee electrodes with loops of coolant pipes on their surface at the Lawrence Hall of Science. ... Enrico Fermi in the 1940s Enrico Fermi (September 29, 1901–November 28, 1954) was an Italian physicist most noted for his work on beta decay, the development of the first nuclear reactor, and for the development of quantum theory. ... Graphite (named by Abraham Gottlob Werner in 1789, from the Greek γραφειν: to draw/write, for its use in pencils) is one of the allotropes of carbon. ... A sphere of plutonium surrounded by neutron-reflecting blocks of tungsten carbide. ... In nuclear physics, a nuclear reaction is a process in which two nuclei or nuclear particles collide, to produce different products than the initial products. ...

A labor strike prevented the construction of the piles at a laboratory in the Argonne forest preserve, so Fermi and his associates Martin Whittaker and Walter Zinn set about building the piles (really the world's first "nuclear reactor," although that term was not used until 1952) in a racquets court under the abandoned west stands of the university’s Alonzo Stagg Field. The piles consisted of uranium pellets as a neutron–producing "core" separated from one another by graphite blocks to slow the neutrons. Fermi himself described the apparatus as "a crude pile of black bricks and wooden timbers." The controls consisted of cadmium-coated rods that absorbed neutrons. Withdrawing the rods would increase neutron activity in the pile to lead to a self-sustaining chain reaction. Re-inserting the rods would dampen the reaction. Argonne National Laboratory is one of the United States governments oldest and largest science and engineering research national laboratories and is the largest in the Midwest. ... Core of a small nuclear reactor used for research. ... 1952 (MCMLII) was a Leap year starting on Tuesday (link will take you to calendar). ... R. P. Keigwin (right) with AEJ Collins the Colleges racquets team at Clifton College circa 1902 Racquets (American English) or rackets (British English) is an indoor racquet sport played in the United Kingdom, United States, and Canada. ... Stagg Field was a stadium in Chicago, Illinois. ... This article or section does not cite its references or sources. ... General Name, Symbol, Number cadmium, Cd, 48 Chemical series transition metals Group, Period, Block 12, 5, d Appearance silvery gray metallic Atomic mass 112. ...

On December 2, 1942, Chicago Pile 1 (CP-1) was ready for a demonstration. Before a group of dignitaries, a young scientist named George Weil worked the final control rod while Fermi carefully monitored the neutron activity. The pile went critical at 3:20 p.m. Fermi shut it down 33 minutes later. In 1943, he rebuilt the pile as CP-2 at the Argonne Laboratory. December 2 is the 336th day (337th in leap years) of the year in the Gregorian calendar. ... 1942 (MCMXLII) was a common year starting on Thursday (the link is to a full 1942 calendar). ... On December 2, 1942, the worlds first artificial self-sustaining nuclear chain reaction took place in the worlds first nuclear reactor, Chicago Pile Number One, shortened as CP-1, built on a racquets court under the abandoned west stands of the Alonzo Stagg Field stadium on the University... 1943 (MCMXLIII) was a common year starting on Friday (the link is to a full 1943 calendar). ...

The stadium was demolished in 1957. The location is commemorated as the Site of the First Self-Sustaining Nuclear Reaction, a National Historic Landmark, featuring a sculpture by Henry Moore. USS Constitution. ... Reclining Figure (1951) outside the Fitzwilliam Museum, Cambridge, is characteristic of Moores sculptures, with an abstract female figure intercut with voids. ...

External links

• The First Pile by Corbin Allardice and Edward R. Trapnell
• Manhattan Project Signature Facilities
• Oak Ridge National Laboratory Review
• Chicago Pile 1 Pioneers
• The First Pile
• The Manhattan Project: Making the Atomic Bomb