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    Re: Polaris in daytime
    From: Greg Rudzinski
    Date: 2012 Jan 25, 06:59 -0800


    I have been able to observe daytime Sirius using a 4 power sextant scope. Since Sirius is 23 times as bright as Polaris then a 92 power scope should do the trick.

    Greg Rudzinski

    [NavList] Polaris in daytime
    From: Geoffrey Kolbe
    Date: 25 Jan 2012 14:31

    Surveyors often need to find true North to lay out the initial
    reference line off which a building is measured. These days, with GPS
    gizmos, there is no difficulty in this. But pre-GPS, true North was
    found by taking a timed azimuth measurement of the sun, or of Polaris
    which, the text books say, is visible during the day using the
    average theodolite 30x scope.

    When I was in Egypt a few years ago doing an experiment on pyramid
    alignment, I tried to find Polaris using my theodolite. I had taken
    azimuth measurements off the sun, so I knew where to look, but I
    never saw nothing. Polaris is too high in these latitudes (Scotland)
    to see with a theodolite, so I am not able to try here.

    Has anyone in lower latitudes managed to see Polaris in the daytime
    through their sextant telescope, or through any other telescope? I
    was wondering how big a telescope you need to see Polaris in the daytime.


    Geoffrey Kolbe

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