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+<sect1 id="tool-solarsys">
+<title>Solar System Viewer</title>
+<indexterm><primary>Tools</primary>
+<secondary>Solar System Viewer</secondary>
+</indexterm>
+
+<screenshot>
+<screeninfo>
+The Solar System Viewer
+</screeninfo>
+<mediaobject>
+  <imageobject>
+    <imagedata fileref="solarsystem.png" format="PNG"/>
+  </imageobject>
+  <textobject>
+    <phrase>Solar System Viewer</phrase>
+  </textobject>
+</mediaobject>
+</screenshot>
+
+<para>
+This tool displays a model of our solar system as seen from
+above.  The Sun is drawn as a yellow dot in the center of the 
+plot, and the orbits of the planets are drawn as ellipses with 
+the correct shapes and orientations.  The current position
+of each planet along its orbit is drawn as a colored dot, along
+with a name label.  The display can be zoomed in and out with
+the <keycap>+</keycap> and <keycap>-</keycap> keys, and the 
+display can be recentered with the arrow keys, or by 
+double-clicking anywhere in the window with the mouse.  You can 
+also center on a planet with the <keycap>0&ndash;9</keycap> keys 
+(<keycap>0</keycap> is the Sun; <keycap>9</keycap> is Pluto).
+If you center on a planet, it will be tracked as time passes in 
+the tool.
+</para>
+<para>
+The Solar System Viewer has its own clock, independent of the 
+clock in the main &kstars; window.  There is a timestep control 
+widget here, similar to the one in the main window's toolbar.  
+However, this control defaults to a timestep of 1 day (so that 
+the motions of the planets can be seen), and it starts out with 
+the clock paused when the tool is opened.
+</para>
+<note>
+<para>
+The current model used for Pluto's orbit is only good for dates 
+within about 100 years of the present date.  If you let the Solar 
+System clock advance beyond this range, you will see Pluto behave 
+very strangely!  We are aware of this issue, and will try to 
+improve Pluto's orbit model soon.
+</para>
+</note>
+</sect1>