Procedure

     J1900 ( Julian Date of 1900.0 JAN 0.5 )

     DOUBLE PRECISION FUNCTION J1900 ( )

Abstract

     Return the Julian Date of 1899 DEC 31 12:00:00 (1900 JAN 0.5).

Required_Reading

     None.

Keywords

     CONSTANTS

Declarations

    None.

Brief_I/O

     The function returns the Julian Date of 1899 DEC 31 12:00:00
     (1900 JAN 0.5).

Detailed_Input

     None.

Detailed_Output

     The function returns 2415020.0, the Julian Date corresponding
     to 1899 DEC 31 12:00:00 (1900 JAN 0.5).

Parameters

     None.

Exceptions

     Error free.

Files

     None.

Particulars

     The function always returns the constant value shown above.

Examples

     The following code fragment illustrates the use of J1900.

        C
        C     Convert Julian Date to UTC seconds past the reference
        C     epoch (J1900).
        C
              SPREF = ( JD - J1900() ) * SPD()

Restrictions

     None.

Literature_References

     None.

Author_and_Institution

     J. Diaz del Rio    (ODC Space)
     W.L. Taber         (JPL)
     I.M. Underwood     (JPL)

Version

    SPICELIB Version 1.0.2, 08-JUL-2020 (JDR)

        Edited the header to comply with NAIF standard.

    SPICELIB Version 1.0.1, 10-MAR-1992 (WLT)

        Comment section for permuted index source lines was added
        following the header.

    SPICELIB Version 1.0.0, 31-JAN-1990 (WLT) (IMU)