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Astro*Dictionary by Michael Erlewine





2 articles for "Sosigenes"

Sosigenes [Astro*Index]


(BC90-?) Greek astronomer.

He believed that Mercury revolved about the Sun. Although his writings on astronomy have been lost, he is best known for his reform of the Roman calendar, at the request of Julius Caesar, in BC46. The Egyptian Lunar Calendar of 365 days consisted of 12 months of 30 days each plus 5 extra days. Being a quarter-day less than the true solar year, it fell behind by one day each four years, making a complete cycle in 1460 years. The Roman lunar calendar (derived from the Egyptian) had been corrupted, due to various manipulations by their priests for political purposes. The Julian Calendar used three years of 365 days, followed by a leap year of 366 days. Not until 1582, when Pope Gregory XIII introduced the Gregorian Calendar was a further improvement made.

See also: ♦ Calendar ♦ Julian Calendar ♦ Gregorian Calendar


Astro*Index Copyright © 1997 Michael Erlewine