//*********************************************************************************
// interface jephem.astro.spacetime.TimeConstants
// Software released under the General Public License (version 2 or later), available at
// http://www.gnu.org/copyleft/gpl.html
//*********************************************************************************
package jephem.astro.spacetime;
/*********************************************************************************
Interface containing constants related with space.
Related methods can be found in class {@link Time}.
@author Thierry Graff
@history feb 15 2002 : Creation from tig.Time.
@todo : remove the labels from coordGroup comments
@todo see if some constants should go to tig API.
**********************************************************************************/
public interface TimeConstants{
//=================================================================================
// PUBLIC CONSTANTS
//=================================================================================
/** Constant used to characterize that a date is expressed in UTC (Universal Coordinated Time). */
public static final int UTC = 0;
/** Constant used to characterize that a date is expressed in TT (Terrestrial Time), which
is considered as equal to TDB (Temps Dynamique Barycentrique) in JEphem. */
public static final int TT_TDB = 1;
/** Number of seconds in a day (24 x 3600 = 86400). */
public static final double SECONDS_PER_DAY = 86400.0;
/** Number of days per millenium ( = 365250). */
public static final double DAYS_PER_MILLENIUM = 365250.0;
/** Number of days per century ( = 36525). */
public static final double DAYS_PER_CENTURY = 36525.0;
/** Number of days per year ( = 365.25). */
public static final double DAYS_PER_YEAR = 365.25;
/** Julian date of 01/01/1900, 12h00m00s TU ( = 2415020.0). */
public static final double JD1900 = 2415020.0;
/** Julian date of 01/01/2000, 12h00m00s TU ( = 2451545.0). */
public static final double JD2000 = 2451545.0;
/** Julian date of 01/01/2100, 12h00m00s TU ( = 2488070.0). */
public static final double JD2100 = 2488070.0;
}//end interface TimeConstants