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    Re: Lunar Distance tables and charts for November 2022
    From: Bela Kovacs
    Date: 2022 Oct 24, 14:31 +0200
    Hello Andrew,

    I'm a bit confused. I recently downloaded Pyalmanac (python 3) because I needed new tables (for example, the "Sun only almanac" does not include meridian pass). I modified the code in a few places.

    In your letter there is SkyAlmanac, in the attached pdf it says SFalmanac. Which project is the right one?

    I would like to use the most up-to-date / future-proof version for my future developments.

    Thank you,
    Bela

    Andrew Bauer <NoReply_AndrewBauer@fer3.com> ezt írta (időpont: 2022. okt. 23., V, 1:47):

    Part 1:
    I have occasionally posted news here about the LD tables and charts I have created using Python. Humble thanks for permitting me to do so.

    Lunar Distance charts are simply a visual aid and depict the data in the LD tables over the passage of 24 hours for any particular day. First let me draw your attention to the fact that I created the charts with a Plate Carrée projection, originally inspired by Bowditch pages 250-251 (2002 Bicentennial Edition) or 246-247 (2017 Edition).

    I was always disappointed with the distortion on a Plate Carrée projection that increases with higher latitudes towards the poles. It is not conformal; local scale varies in every direction (except along the equator); and areas are not comparable. I favour the following quote from Wikipedia:

    “The fundamental problem of cartography is that no map from the sphere to the plane can accurately represent both angles and areas. In general, area-preserving map projections are preferred for statistical applications, while angle-preserving (conformal) map projections are preferred for navigation.” (https://en.wikipedia.org/wiki/Stereographic_projection)

    Before I proceed, the code is published here:

    Sample LD tables and charts (as previously created) for November 2022:

       
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