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    Re: "A Star To Steer Her BY" -- I don't think it's so bad
    From: Bill Noyce
    Date: 2005 Feb 1, 08:49 -0500

    > Now I wish I hadn't.  Chapter 2 has several diagrams that are most
    > upsetting.  They show a FLAT earth with a celestial object so close to
    > earth surface as to suggest the difference in measured angle with the
    > horizon (Ho) is due to the fact that the object's rays are approaching
    at a
    > different angle instead of the object's parallel rays hitting
    > spots on the earth at different angles due to curved surface of the
    > (ignoring horizontal parallax for the moon).
    My first introduction to celnav was a book that included a similar
    diagram (I think it was of a tall street light), and it's served as
    a useful mnemonic ever since to help me remember whether Ho>Hc means
    "toward" or "away".  Yes, the mechanism is wrong, but I don't think
    it hindered my understanding.  Does the book go on to show parallel
    rays hitting a round earth later?

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