First-hand recollections of the first self-sustaining chain reaction

Aug 08, 2012 by Michael Hess

Just seventy years ago, nuclear power, which generates 20 percent of the electricity in the United States, was just a theory. Scientists weren’t entirely sure they could safely create a self-sustaining nuclear reaction, let alone build a nuclear reactor.

On paper, renowned physicists Enrico Fermi and Leo Szilard figured out that if they shot a uranium-235 atom with a neutron, the atom would become unstable and break apart explosively, firing neutrons into surrounding Uranium-235 atoms, which then become unstable, and so on.

Fermi figured they could dampen that enough to avoid a catastrophic runaway reaction, but still achieve a self-sustaining nuclear reaction, thus unleashing the power of the atom. The famous experiment at Chicago Pile 1 proved this theory and ushered science into a new era.

This video is not supported by your browser at this time.
On December 2, 1942, 49 scientists, led by Enrico Fermi, made history when Chicago Pile 1 (CP-1) went critical and produced the world's first self-sustaining, controlled nuclear chain reaction. Seventy years later, two of the last surviving CP-1 pioneers, Harold Agnew and Warren Nyer, recall that historic day.

Starting in November 1942, a team lead by Fermi built an unseemly structure in a converted squash court under an abandoned football field on the University of Chicago campus. Essentially a stack of 380 tons of graphite blocks and uranium slugs shrouded by a wooden frame, the Chicago Pile 1 was literally the world’s first nuclear reactor.

Experiments started at 9:45 a.m. on Dec. 2, 1942. On the floor of the converted squash court, Fermi instructed the scientist manning the control rod, a cadmium-covered wooden pole, how far to withdraw the pole from the center of the pile. At 3:25 p.m., Fermi’s instrumentation lit up. They had achieved criticality – and proved that they could safely generate energy by splitting the atom.

The reaction lasted for 23 minutes before they shut it down. When the instruments fell silent, one of the researchers brought out a bottle of wine he had been saving for their success. The group of 50 scientists drank to their accomplishment in near silence.

Two of the men who worked and celebrated with Fermi, Szilard, and the other scientists in that room that day, Harold Agnew and Warren Nyer, are still alive today. In this new video above, they recall the details of that momentous day.

Explore further: A platform to help consumers achieve sustainable energy consumption

add to favorites email to friend print save as pdf

Related Stories

Lack of fuel may limit US nuclear power expansion

Mar 20, 2007

Limited supplies of fuel for nuclear power plants may thwart the renewed and growing interest in nuclear energy in the United States and other nations, says an MIT expert on the industry.

Plutonium in troubled reactors, spent fuel pools

Mar 18, 2011

(AP) --The fuel rods at all six reactors at the stricken Fukushima Dai-ichi complex contain plutonium - better known as fuel for nuclear weapons. While plutonium is more toxic than uranium, other radioactive ...

China makes nuclear power breakthrough

Jul 22, 2011

China said Friday it had hooked its first so-called "fourth generation" nuclear reactor to the grid, a breakthrough that could eventually reduce its reliance on uranium imports

Iran tests first domestically made nuclear fuel rod

Jan 01, 2012

Iran said on Sunday that its scientists have "tested the first nuclear fuel rod produced from uranium ore deposits inside the country," the website of the Iranian Atomic Energy Organisation said.

Recommended for you

Image: Testing electric propulsion

Aug 20, 2014

On Aug. 19, National Aviation Day, a lot of people are reflecting on how far aviation has come in the last century. Could this be the future – a plane with many electric motors that can hover like a helicopter ...

Where's the real value in Tesla's patent pledge?

Aug 20, 2014

With the much-anticipated arrival next month of electric vehicle manufacturer Tesla's Model S to Australian shores, it's a good time to revisit Tesla's pledge to freely share patents. ...

New type of solar concentrator doesn't block the view

Aug 19, 2014

(Phys.org) —A team of researchers at Michigan State University has developed a new type of solar concentrator that when placed over a window creates solar energy while allowing people to actually see through ...

User comments : 0