Location of tritium in the table of nuclides
|Name, symbol||tritium, triton, 3H|
|Isotope mass||3.0160492 u|
|Excess energy||14,949.794± 0.001 keV|
|Binding energy||8,481.821± 0.004 keV|
|Decay mode||beta emission|
|Decay energy||0.018590 MeV|
|Discoverer||Ernest Rutherford, Mark Oliphant and Paul Harteck|
Tritium (symbol T or 3H, also known as hydrogen-3) is a radioactive isotope of hydrogen. The nucleus of tritium (sometimes called a triton) contains one proton and two neutrons, whereas the nucleus of protium (by far the most abundant hydrogen isotope) contains one proton and no neutrons. Naturally occurring tritium is extremely rare on Earth, where trace amounts are formed by the interaction of the atmosphere with cosmic rays. The name of this isotope is formed from the Greek word "tritos" meaning "third".
Tritium was first predicted in the late 1920s by Walter Russell, but actually produced in 1934 by Ernest Rutherford, Mark Oliphant and Paul Harteck from deuterium. Rutherford was unable to isolate the tritium, although Luis Alvarez and Robert Cornog later did. Willard F. Libby discovered that tritium could be used to date water, and therefore wine.