Wikipedia:Main Page history/2020 March 21
From today's featured articleThe 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. (Full article...)
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On this dayMarch 21: Galactic Tick Day (2020)
Ælla of Northumbria (d. 867) · Evelina Haverfield (d. 1920) · Wolfgang Wagner (d. 2010) |
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Yekaterina Skudina (born 21 March 1981) is a Russian world champion and Olympic sailor. She was awarded the Roy Yamaguchi Memorial Trophy for winning the world championships in the women's Snipe class in 1998, and the bronze medal at the Yngling open world championships in 2007. At the 2011 World Championships, Skudina finished fourth in the Elliott 6m class. In addition, she has competed in three Olympic Games, finishing eighth in the Yngling class in 2004, sixth in the same class in 2008, and fourth in the Elliott 6m class in 2012. This photograph of Skudina, taken in 2009, is part of a collection of 500 images of Russian sportspeople released to Wikimedia Commons by Bolshoi Sport. Photograph credit: Platon Shilikov
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