cdm/src/main/java/ucar/nc2/dataset/conv/Cosmic1Convention.java
public double gast(int iyr, int imon, int iday, int ihr, int imin,
                     double sec, double dsec) {
    //
    //    implicit double precision (a-h,o-z)
    //    character(len=*), parameter :: header = '$URL: svn://ursa.cosmic.ucar.edu/trunk/src/roam/gast.f $ $Id: gast.f 10129 2008-07-30 17:10:52Z dhunt $'
    //
    // Coordinate transform from the celestial inertial reference frame to the geo-
    // centered Greenwich reference frame.
    // Call a subroutine to calculate the Julian day "djd":
    double djd = juday(imon, iday, iyr);  //djd=julean day.
    double tu = (djd - 2451545.0) / 36525.0;
    double gmst = 24110.548410 + 8640184.8128660 * tu
            + 0.093104 * tu * tu - 6.2E-6 * Math.pow(tu, 3);  //       !gmst=Greenwich mean...
    double utco = (ihr * 3600) + (imin * 60) + sec;

    return togreenw(dsec, utco, gmst);
  }
public double gast(int iyr, int imon, int iday, int ihr, int imin,
                     double sec, double dsec) {
    //
    //    implicit double precision (a-h,o-z)
    //    character(len=*), parameter :: header = '$URL: svn://ursa.cosmic.ucar.edu/trunk/src/roam/gast.f $ $Id: gast.f 10129 2008-07-30 17:10:52Z dhunt $'
    //
    // Coordinate transform from the celestial inertial reference frame to the geo-
    // centered Greenwich reference frame.
    // Call a subroutine to calculate the Julian day "djd":
    double djd = juday(imon, iday, iyr);  //djd=julean day.
    double tu = (djd - 2451545.0) / 36525.0;
    double gmst = 24110.548410 + 8640184.8128660 * tu
            + 0.093104 * tu * tu - 6.2E-6 * Math.pow(tu, 3);  //       !gmst=Greenwich mean...
    double utco = (ihr * 3600) + (imin * 60) + sec;

    return togreenw(dsec, utco, gmst);
  }
----------------------------------------------------------------------
gast.f
<p/>
This subroutine computes the Greenwich Apparent Siderial
Time angle given a UTC date and time.
<p/>
parameter  Input parameters:
Inputs:

@param iyr  integer year 1995
@param imon integer month 5
@param iday integer day 5
@param ihr  integer hour 5
@param imin integer minute 5
@param sec  double second 31.0
@param dsec double second 0.0
Outputs:
@return theta GAST angle in radians
<p/>
author     Bill Schreiner
@since May 1995
version    $URL: svn://ursa.cosmic.ucar.edu/trunk/src/roam/gast.f $ $Id: gast.f 10129 2008-07-30 17:10:52Z dhunt $
-----------------------------------------------------------------------