The Manhattan Project

Scientific Discoveries

Cambridge, MA

Harvard University

Harvard became an important center for nuclear physics research during the early twentieth century. After Ernest O. Lawrence constructed the first cyclotron at the University of California at Berkeley in 1929, Harvard physicists and engineers such as Harry Mimno, Kenneth Bainbridge, and Edward Purcell began thinking about building their own cylcotron. In 1936, the construction of the cyclotron began in the Gordon McKay laboratory, a wooden World War I building on the east side of Oxford Street. The magnet in the cyclotron weighed eighty-five tons.

Princeton University

Princeton University was a hotbed for nuclear physics research during the early twentieth century. Much of the research conducted at Princeton allowed scientists to develop and pursue a path to building the world's first atomic device. In fact, more than two dozen Princetonians were among the core group of brains at Los Alamos, N.M.

Jay Wechsler's Interview

Jay Wechsler: Well, my mother was visiting her folks in New York when she decided that it was time, and I was the first child, and I guess she was a little surprised. So I was born in New York even though we didn’t live there. And as soon as we were able we were back in New Jersey, where she and my father lived. My father was a chemist and even at a young age he was always taking me into the plant where he worked, showing me things. And I kind of had a mechanical bend or bent.

George Cowan's Interview (2006)

George Cowan: It's weighted so heavily in favor—not in favor of—but the emphasis on number one Los Alamos, and then Oak Ridge, and then Hanford, as the three secret cities or something. But the fact is the Met Lab at Chicago was enormously important. The Stagg Field reactor was historic in ’42, and its sort of dismissed. 


Located in a bucolic setting surrounded by tall pines, these humble wooden and asbestos-shingled buildings were where the world's first atomic device was assembled. Here scientists, engineers, and explosives experts worked around the clock on the "Gadget," the first plutonium-based atomic explosive.


In early 1944, DuPont, the operating contractor at Hanford, foresaw the need for four chemical separation facilities. These facilities, designated the T and U plants at location 200-West and the B and C plants at location 200-East (the C plant was never built), would be located approximately ten miles south of the reactors.

B Reactor

The B Reactor at Hanford was built and operated by DuPont and was the world's first production-scale nuclear reactor. B Reactor was the first of three plutonium reactors constructed in the 100 area during the Manhattan Project.

Joe Dykstra's Interview

Joe Dykstra: My name is Joe Dykstra, that’s spelled D-Y-K-S-T-R-A. 

Cynthia Kelly: Ok, now you can talk about—

Dykstra: I finished school with a degree in chemistry in May of ’43. I was in Iowa. During that year, I’d filled out an application for a defense job with Hooker Electrochemical Company in Niagara Falls. I didn’t know what I was going to be doing, except it was defense. 

University of California-Berkeley

The "Rad Lab" was the short name for the Radiological Laboratory at the University of California, Berkeley. Its director was Nobel laureate Ernest O. Lawrence. He gained recognition for his 60" cyclotron,  a type of particle accelerator first invented in the early 1930s. Known as “atom smashers,” cyclotrons accelerate atoms through a vaccuum and use electromagnets to induce collisions at speeds up to 25,000 miles per second.


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