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    Re: Refraction near th e Horizon – Observation vs. Calc ulation
    From: Bruce J. Pennino
    Date: 2013 Apr 5, 09:10 -0400
    Thank you for posting this information. The text is just excellent and well written. My math/statistics  background limits me , but I'll study the results.
    I was interested to see that you use the equation for dip 1.76 sq rt H meters, which is the same as 0.971 sq rt H feet.  I gather that this is the universally accepted equation, which I've proven to myself is from basic trig knowing the average radius of the earth? Right?

    ----- Original Message -----
    Sent: Thursday, April 04, 2013 6:28 PM
    Subject: [NavList] Refraction near the Horizon – Observation vs. Calculation

    The following link leads to a first, gross description of the collected measurements, their related data and to two examples showing how the dataset can be used. ( I hope my version of English is sufficently comprehensible.)


    The intention is now trying to find estimates for refraction and dip which agree even better with the measurements than those shown.

    Comments, suggestions and critics are welcome.


    P.S: May be one understands now why I encourage members of NavList to compile a similar dataset with measured dips.

    View and reply to this message: http://fer3.com/arc/m2.aspx?i=123335

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