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get rid of them,  or change their color,  you would click on one of
them with the right mouse button.  You will immediately get a short
bit of information about the object you clicked on (which can help in
"what in the world is _this_?" situations.)  But the dialog box with
that information will also have a "Display" button;  clicking on this
will give you a chance to turn that class of objects on or off,  or
change its color, and (sometimes) adjust magnitude limits and
labelling.
                                                
   Also,  there is a legend at the lower left corner of the chart,
showing the position of the cursor,  the constellation you're in,
the sizes of stars for different magnitudes,  and some other data.
As you move the cursor,  the position readout will be updated.

4:  PANNING AND ZOOMING                            

   To move to another part of the sky, you can move the mouse cursor to
somewhere else on the chart area,  and click on the LEFT mouse button.
A chart will be drawn at the same scale,  but centered at the point you
clicked on. Click on the center of the top of the chart, and you will
see a smaller version of the Big Dipper, with its brightest star at the
tip of the handle. This is Ursa Minor, the Small Bear or Little Dipper.
The bright star is the North Star, Polaris. The arcs of the
constellation boundaries center on (well, very close to)  this star;
it marks the celestial the North Pole. It's only coincidence that gives
us a fairly bright star near the pole right now; the South Pole has no
such luck,  and at many times in the past, no bright star has been near
the North celestial pole either.
                                                       
   There are many ways to zoom out; you may for instance hit , the
divide key. You will then see an area of the sky roughly twice as
large in both height and width. Because you see more sky, some
markings will be dropped out to avoid cluttering the screen: for
instance, the Bayer letters are now omitted. To zoom in, hit <*>, the
asterisk. You'll see the reverse of the Zoom Out process occur. (The
asterisk and division keys can be used at any time and at any level in
the program: they are program-wide hotkeys. A list of program-wide
hotkeys is found on page 82.)  If you have a three-button mouse,
you can click with the center mouse button to combine recentering on
that point with zooming out one level.

   Usually,  whenever you zoom in or out, Guide tries to decide what
level of clutter you would like best. Stars will brighten or dim as
you zoom in or out, and dim stars will drop out as you zoom out and
appear when you zoom in. You may override Guide's judgment through
the Display menu.

   From Level 2, you can zoom out one more level. This takes you to a
point where you see half of the entire sky and only the brightest
stars.  You can keep on zooming in to Level 20,  though there is
usually not much to see past Level 10 or so,  because the stars only

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