Tag: Time

Time Conversions with SPICE

JPL’s SPICE Toolkit (SPICELIB) is the premier software library for computations related to solar system geometry. It is freely distributed, and is also one of the best-documented libraries I have ever come across. SPICELIB also includes a comprehensive set of

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Julian Date

Julian date is a count of the number of days since noon on January 1, 4713 BC in the proleptic Julian calendar.  This epoch was chosen by Joseph Scaliger in 1583 as the start of the “Julian Period”: a 7,980

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The Computus is the algorithm for the calculation of the date of Easter.  The following is a simple Fortran subroutine of the Computus, using the “Meeus/Jones/Butcher” Gregorian Easter algorithm. Note that this subroutine makes use of Fortran integer division. The sequence

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