...Switch to Plot a Different Celestial Coordinate Grid

Once you have set up a PlotPlot to draw a coordinate grid (§3.16), it is a simple matter to change things so that the grid represents a different celestial coordinate system. For example, after creating the Plot with astPlotastPlot, you could use:


\begin{terminalv}
astSet( plot, ''System=Galactic'' );
\end{terminalv}
or:
\begin{terminalv}
astSet( plot, ''System=FK5, Equinox=J2010'' );
\end{terminalv}

and any axes and/or grid drawn subsequently would represent the new celestial coordinate system you specified. Note, however, that this will only work if the original grid represented celestial coordinates of some kind (see §3.8 for how to determine if this is the case[*]). If it did not, you will get an error message.

For more information about the celestial coordinate systems available, see the descriptions of the SystemSystem, EquinoxEquinox and EpochEpoch attributes in Appendix C.