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regions where the sun is above or near the horizon.  Also,  regions
where an eclipse is partial will be shown in various shades.  (Keeping
in mind that,  for occultations of stars,  there is no such thing as a
"partial eclipse".)

   Of course,  it's always possible that Guide won't find an eclipse,
because one didn't happen that time.  If the moon is one of the two
objects you clicked on,  Guide will again be bright enough to check
for eclipses in subsequent months until it finds one.  It can apply
a similar search for transits of Mercury and Venus.  In all other
cases,  you'll get an "Eclipse not found!" message if the event
isn't visible from Earth.

   Many of the techniques used in drawing sky charts have been recycled
for the earth/eclipse charts.  You can zoom in or out,  print charts,
set display levels,  and so forth much as you did before.  If you
right-click on the chart,  you can get contact times for the event
as seen from that point.  The menus are heavily rearranged to cut out
options such as "star display" that make sense for charts of the stars,
but which are meaningless for charts of the earth.

   If the event is a lunar one or a transit of Mercury or Venus,  you
can use the "Next" and "Previous" options at the top to search for
the following or preceding event.

   If you've zoomed in beyond the world map level,  you can use "Go To...
Country",  and Guide will give a list of countries.  Select one,  and
the eclipse chart will recenter on that country.  Or you can use "Go
To... City",  and Guide will list all cities in the current chart
area.  (So you might zoom in on,  say,  Australia,  and only then use
this option to list cities in that country.)  Select one,  and Guide
will recenter the eclipse chart on that city.

   Two options in the "Extras" menu are deserving of mention.  Suppose
you want to know when the next eclipse visible in London is.  You
would zoom in on that city,  putting it at the center of the chart;
and toggle the "Local Events Only" option in the Extras menu.  The
"Next" and "Previous" options will then keep searching until they find
an event visible from that point.

   In the case of solar eclipses,  there may be a lot of partial events
found in this manner.  So you could then toggle off the "Partial Events"
option in the Extras menu.  Doing that would force Guide to insist not
only on events visible from London,  but that they be total or annular
as well. This makes determining the next total eclipse visible from a
given point quite easy to do.

   Finally,  when done,  you can go back into the Extras menu and click
on "Show Eclipse" again,  and Guide will return to charting stars.

19:  SAVING AND GOING TO MARKS         


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