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Re: Beginner Meridian Passage Question

From: Noyce, Bill (no email)
Date: Fri Sep 03 2004 - 09:13:03 EDT

  • Next message: Zorbec Legras: "Re: Beginner Meridian Passage Question"

    > > b) when you think Polaris is directly below or above the pole, add
    or
    > > subtract its difference (which you have memorized as about 45');
    >
    > It looks to me that the average declination for Polaris in 2004 was
    close to 89 d 17'. 90 - > 89 d 17' = 43'. Am I missing some 2nd and
    3rd order variables when calculating the distance > of Polaris from PN?
    Id so, what?

    For lifeboat navigation, I was assuming (1) a couple of minutes / miles
    doesn't matter;
    (2) a round number was easier to remember; and (3) I had the impression
    Polaris had
    already passed as close to the pole as it was going to, and was now
    slowly moving away.
    I now believe #3 is wrong -- it looks to me as if that happens around
    2008, though the
    motion is less than 0.1' every few years.

    So if you can remember 44' or 43', use that.
            -- Bill


  • Next message: Zorbec Legras: "Re: Beginner Meridian Passage Question"



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