The Dutch Occultation Association recently developed a
software program (MoonView) for lunar occultation observers.
The main reason we have built this application has to do with the
uncertainty of the location where to expect a star when it is
reappearing behind the lunar limb. Especially when the lunar phase is
100% - 80% waning, many observers encouter difficulty in finding the
proper place of the star. During these phases the cusp angle isn't very
reliable, because no one knows exactly where the cusps are positioned.
This problem is fully solved by MoonView.

The program, that runs on both Windows 95 and Windows NT clients, draws
a chart of the Moon on the screen taking both librations of the Moon and
geographical position of the observer into account. After entering a
time (UT) and position angle of the star, the picture is created and the
place of reappearance can be determined by means of the features visible
on the Moon. In practice it is best to pick out two well visible craters
situated on an imaginary line passing through the star.

In The Netherlands MoonView has proven to be very successful; in the
past the limiting magnitude for a 15 cm telescope was approximately
magnitude 8 for a 90% sunlit waning Moon. When the place of reappearance
is know very accurately on beforehand, this limit may increase to
magnitude 9 (!) or fainter as a result of the higher magnification that
can be applied.

Because we think MoonView may be very useful for other observers as
well, I will mail you a copy of this 32-bit application. Ofcourse it may
be freely distributed by IOTA without any charge; the more people use
it, the better.
MoonView is distributed on two diskettes. Because a lot of people have
access to e-mail, the distribution procedure is somewhat modified. The
procedure for e-mail distribution is given below. The files 'disk1.exe'
and 'disk2.exe', both described in the procedure, will be attached to
seperate mails.

With kindest regards,

Adri Gerritsen
Dutch Occultation Association


STEP 1: Take two blank formatted floppy disks 1.44 Mb each.

STEP 2: Create two teporary directories, for example "C:\DISK1" and

STEP 3: Copy file 'disk1.exe' to "C:\DISK1" and file 'disk2.exe' to

STEP 4: Unzip the self-extracting zipfile "C:\DISK1\DISK1.EXE" to

STEP 5: Unzip the self-extracting zipfile "C:\DISK2\DISK2.EXE" to

STEP 6: Remove both "C:\DISK1\DISK1.EXE" and "C:\DISK2\DISK2.EXE" files.

STEP 7: Copy the contents (13 files) of "C:\DISK1" to floppy number '1'.

STEP 8: Copy the contents (7 files) of "C\DISK2" to floppy number '2'.

STEP 9: Remove the directories "C\DISK1" and "C:\DISK2".


STEP 1: Place floppy number '1' in the diskdrive.

STEP 2: Start the program 'setup.exe.

STEP 3: Follow the instructions given in the installation procedure.

MoonView will be automatically registered by the Windows system and is
ready for use now.

Note: After starting MoonView, the system date and -time are shown by
default. The co-ordinates of the observer and orientation of the chart
have to be entered only once; their values can be saved by choosing
"Save positon" and "Save settings" respectively.

In order to operate properly, the PC running MoonView:

- has a 80486 processor or higher
- has 8 Mb RAM or more
- runs Windows 95 or Windows NT
- has 65 thousand colors or more
- has a resolution of 800 x 600 pixels

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