00:00 Uranium is a controversial element with both power and destructive capabilities that is not well understood by most people.

01:41 Uranium, the heaviest natural element with an atomic number of 92, has been used by humans for at least 2000 years and was first identified by Martin Heinrich Klapproth in 1789, who named it after the planet Uranus.

03:10 In 1896, Henri Becquerel discovered the radioactivity of uranium, which has two naturally occurring isotopes, uranium-238 and uranium-235, with uranium-238 being the more abundant isotope.

05:05 Enrico Fermi discovered that uranium-235 could sustain a chain reaction by releasing enough neutrons when it split, leading to the creation of the world's first artificially-sustained, chain nuclear fission reaction in 1942, which was the basis of the atomic bomb in the Manhattan Project.

06:56 Enrichment is the process of separating uranium-235 from uranium-238, which is done by creating a gas called uranium hexafluoride and using centrifugation to separate the isotopes, resulting in different concentrations of isotopes, with nuclear reactors requiring about 5% uranium-235 and atomic bombs requiring 90-95% uranium-235, while the remaining uranium-238 is called depleted uranium.

08:44 Uranium has various uses including as armor in tanks, in anti-tank ammunition, as radiation shielding in medical equipment, and it was even used in the glazing of Fiestaware dishes until 1972.

10:22 Two billion years ago, there was evidence of a natural nuclear fission reaction in Gabon, Africa, indicating that a naturally occurring nuclear reactor is possible, although it would have been very weak.