From today's featured articleRigel is a blue supergiant star in the constellation of Orion, approximately 860 light-years (260 pc) from Earth. It is the brightest and most massive component of a star system of at least four stars that appear as a single blue-white point of light to the naked eye. A star of spectral type B8Ia, Rigel is calculated to be anywhere from 61,500 to 363,000 times as luminous as the Sun, and 18 to 24 times as massive. Its radius is over 70 times that of the Sun, and its surface temperature is 12,100 K. Rigel varies slightly in brightness, its apparent magnitude ranging from 0.05 to 0.18. It is classified as an Alpha Cygni variable. It is generally the seventh-brightest star in the night sky and is usually the brightest star in Orion, though it is occasionally outshone by Betelgeuse. With an estimated age of 7 to 9 million years, Rigel has exhausted its core hydrogen fuel, expanded and cooled to become a supergiant. It will end its life as a type II supernova. (Full article...)
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On this daySeptember 28: Meskel in Ethiopia and Eritrea (2020)
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The Bishop of Hong Kong is the head of the Roman Catholic Diocese of Hong Kong, and responsible for looking after its spiritual and administrative needs. The Diocese of Hong Kong is nominally part of the ecclesiastical province of Canton and thus is a suffragan of that archdiocese. However, it has been exempt in practice since 1951, when the People's Republic of China severed diplomatic relations with the Holy See. As a crown colony of the United Kingdom at the time, Hong Kong was unaffected by this and relations with the Vatican continued unabated. Consequently, the bishop of Hong Kong answers "directly to the Holy See". The current bishop is John Tong Hon (pictured), who served as the diocese's thirteenth ordinary from 2009 until 2017, and is presently its apostolic administrator following the death of his successor, Michael Yeung, in 2019. Eight men have been Bishop of Hong Kong; another six were heads of its antecedent jurisdictions. Three bishops – John Baptist Wu, Joseph Zen, and John Tong Hon – were elevated to the College of Cardinals. (Full list...)
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Silver certificates are a type of representative money issued between 1878 and 1964 in the United States as part of its circulation of paper currency. This $50 silver certificate, part of the series of 1878, depicts Edward Everett, an American politician, pastor, educator, diplomat, and orator from Massachusetts who served as Secretary of State from 1852 to 1853. The series is known for the ornate engraving on the reverse of the notes. This banknote is part of the National Numismatic Collection at the Smithsonian Institution. Credit: Bureau of Engraving and Printing; photographed by Andrew Shiva
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