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    Re: Pub. 249 question
    From: David Pike
    Date: 2017 Nov 26, 14:58 -0800

    Has anyone any idea what “continuity” means in the explanation in AP3270/HO249 where it says “Continuity was sought in regard to both latitude and hour angle, particularly for latitude where changes are not immediately evident by inspection”?

    Bearing in mind that much celestial from aircraft was pre-computed, and looking at the circular motions centred on Polaris, which one sees in the long exposure photographs which turn up in newspapers periodically, it’s clear that Hc must vary slowly over top and around the bottom, which gives you more tolerance over the shot time but mucks up averaging sandwich fixes, and varies fastest when the star races straight up or down which is probably better for averaging but less gives tolerance over timing, is this anything to do with it? DaveP

       
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