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    Re: Celestial Navigation Through Clouds
    From: Tom Sult
    Date: 2009 Dec 18, 12:09 -0600

    One might afix a infared scope to the sextan to detect the sun through
    the clouds. The semi might be hard to figure.
    
    Thomas A. Sult, MD
    Sent from iPhone
    
    On Dec 18, 2009, at 1:43, frankreed{at}HistoricalAtlas.com wrote:
    
    > Bruce, you wrote:
    > " I know from time to time the list members come up with ideas on
    > sextant improvements, and I was wondering if it would be possible to
    > make the cloud cover a non-issue."
    >
    > Sure. Put a tall mast amidships, let's say 40,000 feet high, and
    > then you send the guy with the sextant up the rigging... :->
    >
    > You mentioned surveyors shooting Polaris in daylight. The stars can
    > definitely be detected in daylight. They're there. They're not
    > fainter. But their faint signal sits on top of the bright daylight
    > sky background. It's hard to pick out. Unfortunately, clouds are a
    > different problem. With rare exceptions, clouds thoroughly scatter
    > all light that passes through them. Even finding the position of the
    > Sun through anything but very thin clouds is hopeless except in rare
    > cases (or using wavelengths far outside the visual spectrum).
    >
    > -FER
    >
    > --
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