edu.nrao.sss.astronomy
Class StarlinkPalConverter

java.lang.Object
  edu.nrao.sss.astronomy.StarlinkPalConverter

All Implemented Interfaces:

CelestialCoordinateConverter

public class StarlinkPalConverter
extends Object
implements CelestialCoordinateConverter

A coordinate converter based on the Positional Astronomy Library of the defunct Starlink project. This class enlists the help of their Pal, which is a partial implementation of their SLALIB software.

This converter handles only the J2000 Equatorial, Ecliptic, and 1958 Galactic coordinate systems.

Version Info:

$Revision: 1707 $

$Date: 2008-11-14 10:23:59 -0700 (Fri, 14 Nov 2008) $

$Author: dharland $ (last person to modify)

Since:

2008-02-28

Author:

David M. Harland

Constructor Summary

StarlinkPalConverter()

Method Summary

SkyPosition

createFrom(SkyPosition position, CelestialCoordinateSystem toSystem, Epoch toEpoch, EarthPosition observer, LocalSiderealTime lst) Returns a new position that is equivalent to position, but in the given coordinate system and epoch.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

StarlinkPalConverter

public StarlinkPalConverter()

Method Detail

createFrom

public SkyPosition createFrom(SkyPosition position,
                              CelestialCoordinateSystem toSystem,
                              Epoch toEpoch,
                              EarthPosition observer,
                              LocalSiderealTime lst)
                       throws CoordinateConversionException

Description copied from interface: CelestialCoordinateConverter

Returns a new position that is equivalent to position, but in the given coordinate system and epoch.

Specified by:

createFrom in interface CelestialCoordinateConverter

Parameters:

position - the position to be converted.

toSystem - the coordinate system for the returned position.

toEpoch - the epoch for the returned position. Unless the toSystem is EQUATORIAL, this value will probably not be used.

observer - the location of the the observer. Unless one of the coordinate systems is HORIZONTAL, this value will probably not be used.

lst - the local sidereal time at the observer's location. This value is important when one of the coordinate systems is HORIZONTAL. However, it can be used for all systems in order to get the coordinates of position at a particular point in time. If this value is null and neither of the coordinate systems is HORIZONTAL, the coordinates of position will be determined as of the time on the system clock.

Returns:

a new position that is equivalent to position, but is expressed in a coordinate system of toSystem for epoch toEpoch.

Throws:

CoordinateConversionException - if anything goes wrong during conversion.