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Julian year

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Also known as a, year, mean Julian year

unit of time and a version of the year often used in astronomy

Wikidata facts

Subclass of
year
Show 5 more facts
conversion to SI unit
31557600
conversion to standard unit
525960
unit symbol
a
Wikidata SPARQL query equivalent
wd:Q217208 p:P2370/psn:P2370 [wikibase:quantityAmount ?source; wikibase:quantityUnit ?base]. ?item p:P2370/psn:P2370 [wikibase:quantityAmount ?target; wikibase:quantityUnit ?base]. BIND(?source / ?target as ?value)
different from
Julian calendar
Sources (2)

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Encyclopedic overview

In astronomy, a Julian year (symbol: a or aj) is a unit of measurement of time defined as exactly 365.25 days of 86400 SI seconds each. The length of the Julian year is the average length of the year in the Julian calendar that was used in Western societies until the adoption of the Gregorian Calendar, and from which the unit is named. Nevertheless, because astronomical Julian years are measuring duration rather than designating dates, this Julian year does not correspond to years in the Julian calendar or any other calendar, nor does it correspond to the many other ways of defining a year.

Usage

Excerpted from Wikipedia’s “Julian year” article, available under the CC BY-SA 4.0 licence.