Back Añu xulianu (astronomía) AST Any julià Catalan Juliánský rok Czech Julianisches Jahr German Año juliano (astronomía) Spanish Juliuse aasta Estonian Juliotar urte (astronomia) Basque سال ژولینی (اخترشناسی) Persian Année julienne French שנה יוליאנית (אסטרונומיה) HE
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.[1][2][3][4] 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.
- ^ P. Kenneth Seidelmann, ed., The explanatory supplement to the Astronomical Almanac, (Mill Valley, Cal.: University Science Books, 1992), pp. 8, 696, 698–9, 704, 716, 730.
- ^ "Measuring the Universe". International Astronomical Union. Retrieved March 22, 2012.
- ^ International Astronomical Union. "Recommendations Concerning Units". Archived from the original on February 16, 2007. Retrieved February 18, 2007. Reprinted from the "IAU Style Manual" by G.A. Wilkinson, Comm. 5, in IAU Transactions XXB (1987).
- ^ Harold Rabinowitz and Suzanne Vogel, The manual of scientific style (Burlington, MA: Academic Press, 2009) 369.