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The graze prediction .zip file includes the following:
A summary list of all the grazes selected for the observer, in a
file named Date1 to Date 2 Graze Summary for [station name].txt
The dates are in YYYYMMDD form.
For each graze, a data file giving the path and other information
about the graze, similar to the Grazereg predictions, but with
no printer profiles, in a file named Date Graze of [star #]
[station name].txt
For each graze, an image file (.jpg) for the predicted profile, in a
file named Date Graze of [star #] [station name].jpg . The
profiles are similar to those of Grazereg, but being line drawings
they are more detailed, showing a detailed jagged curve for the
Kaguya profile, and then all the past graze observations (that
have been reported to IOTA recently, or converted from the ILOC
and HMNAO observation files) in the range of this predicted
profile, shown as small circles (video or photoelectric,
"instumental"), squares (visual or instrumental), or +'s (visual).
Comparison of the Kaguya and Watts profiles with past graze
observations show that the Kaguya profile data are very much
better than the Watts data. Although the comparisons have found
some errors in parts of the Kaguya data, the differences are quite
small and negligible for prediction purposes. The differences
that you see in the plotted past observations from the Kaguya
profile are more due to the difference in the librations at the
time the observations were made from those used to generate the
predicted profile, than to actual errors in the Kaguya data.
For each graze, a .kml file that can be used with Google Earth to
plot the predicted limit line. Although useful to see where the
graze path is located, I find more useful the GoogleMap Web sites
such as Brad Timerson's described below that can be used to also
specify offsets from the predicted limit line that can be
determined from the predicted profile to define the better zones
from which the most multiple events might be observed.
A map showing all grazes for the time period in the region, not just
the ones selected for the observer. The map has index numbers at
the west and east ends of the paths, and includes as dots all
stations in the .site file. The file name is Regional Grazes -
xxxxxx.jpg where xxxxxx is the file name (without ".site") of the
.site file for the region (such as argz10). For the whole year,
the plot is usually so dense with lines as to be virtually
useless. It includes dots showing the locations of all stations
in the region for which predictions have been generated.
A table of all the grazes for the time period in the region, not
just the ones selected for the observer. The index # given on the
map is in the first column, followed by the date & time of the
event, the star numbuer and magnitudes, the percent sunlit
(illuminated) of the Moon and whether waxing (+) or waning(-), the
Elon(gation) in deg. from the Sun, and the cusp angle of the
graze. The file name is Regional Grazes - xxxxxx.txt where
xxxxxx is the file name (without ".site") of the .site file for the
region.
These predictions are all largely self-explanatory, being similar to
those distributed in past years. They are described in the Occult
documentation; if you have Occult 4, click on "Help" in the upper
left, then click on the "+" to the left of "Lunar Predictions" to
expand that, then click on the "+" to the left of "Graze Predictions".
The main item there is the Graze profile; there isn't a separate
description of the path information, since the column headings, etc.,
make that self-explanatory.
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