One date across Gregorian, Julian, Hebrew, Islamic and more
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Julian Day Number:—
Conversions go through the astronomical Julian Day Number. The Julian, Coptic and Ethiopian calendars use the proleptic (extended back in time) form; the Islamic calendar uses the arithmetic (tabular) version, which can differ by a day from sightings of the new moon. Juche (North Korean) numbering counts from 1912 = Juche 1 and otherwise follows the Gregorian calendar.