<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. You may set the date to now 
by pressing the <guibutton>Today</guibutton> button.
</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>
