>  Docs Center  >  Libraries  >  JHU/APL/S1R  >  SUN






      Computes geocentric physical ephemeris of the sun.


Calling Sequence

      sun, y, m, d, et


      y = year. in
      m = month number. in
      d = monthday number. in
      et = ephemeris time in hours. in
        Delta T = ET - UT which is not completely
        predictable but is about 1 minute now.
        This difference is noticable slightly.

Keyword Parameters


        /LIST displays values on screen.
        DIST = distance in AU.
        SD = semidiameter of disk in arc seconds.
        TRUE_LONG = true longitude (deg).
        TRUE_LAT = 0 always.
        APP_LONG = apparent longitude (deg).
        APP_LAT = 0 always.
        TRUE_RA = true RA (hours).
        TRUE_DEC = true Dec (deg).
        APP_RA = apparent RA (hours).
        APP_DEC = apparent Dec (deg).
        LAT0 = latitude at center of disk (deg).
        LONG0 = longitude at center of disk (deg).
        PA = position angle of rotation axis (deg).
CARRINGTON = Carrington rotation number.


Common Blocks


      Notes: based on the book Astronomical Formulae
        for Calculators, by Jean Meeus.
        If no arguments given will prompt and list values.

Modification History

      R. Sterner, 19 Feb, 1991
24 July, 1991 --- added Carrington Rotation number
based on an equation from Howard Cohl, Sac Peak.
      R. Sterner, 2010 Jun 04 --- Converted arrays from () to [].
  Copyright (C) 1991, Johns Hopkins University/Applied Physics Laboratory
  This software may be used, copied, or redistributed as long as it is not
  sold and this copyright notice is reproduced on each copy made. This
  routine is provided as is without any express or implied warranties
  whatsoever. Other limitations apply as described in the file disclaimer.txt.

© 2020 Harris Geospatial Solutions, Inc. |  Legal
My Account    |    Store    |    Contact Us