Hydrogen isotope biogeochemistry spectroscopic lines for publishable data, Murphy and Urey paired with Ferdinand Brickwedde and distilled a more concentrated pool of heavy hydrogen, known today as deuterium. This work on hydrogen isotopes won Urey the 1934 Nobel Prize in Chemistry. Also in 1934, scientists Ernest Rutherford, Mark Oliphant, and Paul Harteck, produced the radioactive isotope tritium by hitting deuterium with high energy nuclei. The deuterium used in the experiment was a generous gift of heavy water from the Berkeley physicist Gilbert N Lewis. Bombarding deuterium produced two previously undetected isotopes, helium-3 and hydrogen-3. Rutherford and his colleagues successfully created tritium, but incorrectly
Hydrogen isotope biogeochemistry today's deuterium originated from this proton-proton fusion after sufficient cooling. Tritium, or hydrogen-3, with one proton and two neutrons, was produced by proton and neutron collisions in the early universe as well, but it has since radioactively decayed to helium-3. Modern tritium cannot be explained by big bang nucleosynthesis because of tritium's short half-life of 12.3 years. Today's tritium concentration is instead governed by nuclear reactions and cosmic rays. The radioactive beta decay of tritium to helium releases an electron and an antineutrino, with an average energy release of 18.6 MeV. It is important to note that this is classified