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    Re: Ah, give someone a calculator.......
    From: Tom Sult
    Date: 2010 Aug 15, 15:27 -0500

    I'm confident it will be done!
    Thomas A. Sult, MD
    Sent from iPhone
    On Aug 15, 2010, at 12:50, Gary LaPook  wrote:
    > I'm just trying to figure out how you would measure 8000 SM visibility. The 
    distance to the horizon is calculated with the formula of 1.35 times the 
    square root of the height above the sea which gives you the distance in 
    statute miles (from table 12 in Bowditch.) The highest point on earth is Mt. 
    Everest at 29,035 feet above sea level. Applyiung the formula, the distance 
    to the sea horizon from the top of Mt. Everest (assuming no intervening 
    obstructions) is 230 SM. Even assuming another mountain as high as Mt. 
    Everest existed and that the two were separated by an unobstructed sea 
    horizon, the maximum distance that you could see between these peaks is twice 
    as much, 460 SM so it appears the maximum visibility that could ever be 
    measured on the surface of the earth is only 460 SM, much less that the 8000 
    SM given in the Weather Underground weather report.
    > Giving it some  more thought, since the maximum diameter of the earth is 
    only 7926 SM, to be able to measure 8000 SM you would need to drill a hole 
    through the center and out the opposite side and then have a satellite fly 
    over the opposite opening at an altitude of 74 SM and shine a powerful light 
    down through the hole so that you can see it from your side.
    > gl
    > Marcel Tschudin wrote:
    >> Trying here different settings:
    >> I don't get the language mixture as you seem to have. All is shown in
    >> English, my selected language, because the translations are bad. The
    >> value for the visibility is definitely wrong. Regarding the pressure:
    >> When I started to use to use their archived data, I had first some
    >> difficulties to find out what the "strange" values around 30 would
    >> correspond to.
    >> Marcel

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