The island of stability in nuclear physics is a predicted set of isotopes of superheavy elements whose half-lives may be considerably longer than those experimentally observed for these elements. Its theoretical existence is attributed to stabilizing effects of closed nuclear shells and magic numbers of protons and neutrons. The island of stability is generally thought to center near copernicium and flerovium isotopes with around 184 neutrons, separated from known stable and long- lived nuclides. While stabilizing effects are expected to be greatest for nuclides with around 114 protons, other islands of stability might also exist around heavier nuclides with higher magic numbers. Estimates of the stability of elements on the island are usually around a half- life of minutes or days, with some estimates of up to millions of years. The synthesis of nuclides with up to 118 protons and 177 neutrons has demonstrated a slight stabilizing effect supporting the island's existence. Read more: <https://en.wikipedia.org/wiki/Island_of_stability> _______________________________ Today's selected anniversaries: 1814: War of the Sixth Coalition: At the Battle of Arcis-sur-Aube, Napoleon suddenly realized his army was vastly outnumbered and hurriedly ordered a retreat. <https://en.wikipedia.org/wiki/Battle_of_Arcis-sur-Aube> 1937: The papal encyclical Mit brennender Sorge, condemning antisemitism and criticizing Nazism, was read from the pulpits of all German Catholic churches. <https://en.wikipedia.org/wiki/Mit_brennender_Sorge> 1960: Police in Sharpeville, South Africa, opened fire on a group of unarmed black demonstrators (depicted) who were protesting pass laws, killing almost 70 people and wounding about 180 others. <https://en.wikipedia.org/wiki/Sharpeville_massacre> 1980: Dallas aired its "A House Divided" episode, which led to eight months of international speculation regarding "Who shot J.R.?" <https://en.wikipedia.org/wiki/A_House_Divided_%28Dallas%29> _____________________________ Wiktionary's word of the day: carceral: (formal or literary) Of or pertaining to imprisonment or a prison. <https://en.wiktionary.org/wiki/carceral> ___________________________ Wikiquote quote of the day:   Nobody grows old merely by a number of years. We grow old by deserting our ideals. Years may wrinkle the skin, but to give up enthusiasm wrinkles the soul.   --Samuel Ullman <https://en.wikiquote.org/wiki/Samuel_Ullman>