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    Re: Predictor for moon alt/az at twilight?
    From: Fred Hebard
    Date: 2005 Apr 1, 08:29 -0500

    The MICA program, produce by the Naval Obseratory, is linked on their
    site.  I think you can buy it from Wilhemm-Bell.  It outputs the
    complement of the declination, but you can easily change that by
    pasting the output into a spreadsheet.
    On Apr 1, 2005, at 6:07 AM, Jim Thompson wrote:
    > For the past couple of springs I have planned the best opportunities
    > for
    > practising 3-body twilight fixes at nearby Point Prim during the warm
    > months.  We have nearly 270d horizon at that location.  The criteria
    > for a
    > good viewing night include having the moon with sufficient
    > illumination, and
    > within a good alt/az window for beginners.
    > The tables I can make at http://aa.usno.navy.mil/data/ are very
    > helpful in
    > providing all the rest of the data I need for this, but they do not
    > offer
    > one particular printout:
    > Is there an online calculator, downloadable program or spreadsheet that
    > would allow me to print out the altitude and azimuth of the moon at a
    > given
    > hour for a specific lat/long position at civil twilight daily for a
    > period
    > of several months?  I can find lots of ways to predict the alt/az for a
    > given day, but I want to build a table to print on one page the moon's
    > alt/az for all the days in the coming months, at a given hour.
    > Header: Moon altitude and azimuth at civil twilight by day for the
    > Period
    > ___ to ___ at Position Lat __ Long ___.
    > Columns: Month/Day, Morning CT, Moon Altitude, Moon Azimuth, Evening
    > CT,
    > Moon Altitude, Moon Azimuth.
    > Rows: Day of the month.
    > Instead of civil twilight, the table could be generated for a set hour
    > in
    > the morning and a set hour in the evening, and then I could pick out
    > days of
    > the month where the moon is likely to be in about the right position,
    > and
    > work out the precise results for each of those days manually.
    > Jim Thompson
    > http://jimthompson.net/boating/Celestial_Navigation.htm
    > --------------------
    > Outgoing email scanned by Norton Antivirus

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