Aloysius Lilius

Aloysius Lilius (c. 1510 – 1576), also Luigi Lilio or Luigi Giglio (or Aluise Lilio or Aloisius Lilius), was an Italian doctor, astronomer, philosopher and chronologist who devised the Gregorian Calendar.Lilius crater on the Moon is named for him. In computer science, the Lilian date is the number of days since adoption of the Gregorian Calendar, on 14 October 1582.
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