Willis Resilience Expedition of the deposition rate of Tritium, a radioactive isotope of hydrogen, across Antarctica. The relatively short half-life of Tritium means it can be used to date snow and ice up to around 150 years old. The data can then be used to better understand the global water cycle, which is intrinsically linked to changes in climate. This will be the first large-scale study of Tritium in Antarctica since Tritium returned to normal levels following the spike caused by thermonuclear tests in the 1960s. The samples will be sent to GNS Science, a New Zealand Crown Research Institute, for analysis. Once
Isotope (counting as stable), and 26 elements have only a single stable isotope (of these, 19 are so-called mononuclidic elements, having a single primordial stable isotope that dominates and fixes the atomic weight of the natural element to high precision; 3 radioactive mononuclidic elements occur as well). In total, there are 253 nuclides that have not been observed to decay. For the 80 elements that have one or more stable isotopes, the average number of stable isotopes is 253/80 = 3.1625 isotopes per element. The proton:neutron ratio is not the only factor affecting nuclear stability. It depends also on evenness or