Commercial nuclear reactors all work pretty much the same way. Atoms of a radioactive material split, emitting neutrons.

Two billion years before we made history and split the atom, the Earth had already accomplished it and was running its own ...

Seventy years have passed since a team of 49 scientists, led by Italian-born Enrico Fermi, succeeded in creating the world's first self-sustaining nuclear chain reaction. Seventy years have passed ...

Photo by Bortzells Esselte, courtesy AIP Emilio Segre Visual Archives. Enrico Fermi (1901-1954) left Italy in 1938 to receive the Nobel Prize for physics in Sweden. He never went back. He and his wife ...

Nuclear weapons haven’t been tested in the United States since 1992. Find out why, and what could happen if the hiatus ends.

December — Dr. Enrico Fermi achieves the first controlled nuclear chain reaction, with a natural uranium device moderated with graphite. Fermi conducted the process using the first demonstration ...

The United States maintains an arsenal of thousands of nuclear weapons, but it hasn't tested one in decades. Instead, the U.S. is using simulations and experiments to see if the nukes still work.

A small US nuclear startup has quietly crossed a threshold that most young fission companies only talk about, achieving a self-sustaining chain reaction in a test system without ever boiling water or ...

Clarity is key on most issues relating to nuclear weapons, and testing them is no exception. America’s adversaries are carrying out low-level nuclear tests and gaining an advantage over the United ...

Men work inside of a uranium conversion facility just outside the city of Isfahan, Iran, on March 30, 2005. The facility in Isfahan made hexaflouride gas, which was then enriched by feeding it into ...