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The V-2 rocket is tested and used in warfare. in used and tested is rocket V-2 The

Two fundamental discoveries made in the United States support military technology. Glenn Seaborg and colleagues bombard The liquid-fueled V-2 uranium in a cyclotron and rocket is tested at produce the fissionable element Peenemunde in Germany, plutonium, one of nine new under the technical elements heavier than uranium direction of the German that Seaborg would help discover. engineers Wernher von John Dunning and co-workers Braun & Walter show that uranium-235 is a Dornberger. It is first used fissionable form of uranium and in warfare in 1944. The element plutonium is develop a method to isolate this produced, and isotope. Plutonium-239 & uranium-235 is isolated. uranium-235 become essential for the atomic bomb.

Carbon dating The first programmable 1946 is invented. electronic digital 1946 is completed. The ENIAC (Electronic Numerical Integrator History and Comparator) computer, based on vacuum tubes, goes into service at the University of Pennsylvania. It is electronic, digital, and programmable -- features that are 1946-1953 still essential in modern . The American chemist Willard Frank Libby shows how to find the date of death of living organisms by measuring the decay of radioactive carbon-14. Radiocarbon dating is accurate back to 50,000 years ago, and is widely used by archeologists, anthropologists, and earth scientists. The 1947 is invented. The American John Bardeen, & Walter Brattain invent the transistor, an electronic amplifier made from a small piece of semiconducting material. It is the forerunner of integrated circuits and memory chips. 1948 The first computerized weather The modern prediction is made. theory of and 1950 electrons is Using the newly invented ENIAC computer, the American formulated. mathematician and computer pioneer John von Neumann and colleagues make the first computerized 24-hour weather predictions 1952 The American physicists Richard A characteristic Feynman & , and the signal is Japanese Sin-Itiro Tomonaga observed from develop quantum electro-dynamics interstellar (QED), the first complete theory of the hydrogen interaction of photons and electrons. The American physicists Harold Ewen (left) & Edward Mills The first commercial Purcell observe a radio signal of 21-centimeter wavelength electronic computer is built. from hydrogen atoms in space, 1951 providing a way to trace this The basic building material of the American universe. engineers John Mauchly & The British biologists Maurice Wilkins & Francis Crick, John Eckert together with the American construct biologist , 1953 discover the double helical UNIVAC I, structure of the complex with 5,000 The double vacuum organic molecule that encodes genetic information. tubes and helix structure data storage is proposed on magnetic for DNA. tape. In 1952 a UNIVAC computer compiles polling results that anticipate the result of the election of U.S. President Eisenhower.