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Re: refraction formula comparison
From: JC Sutherland
Date: 2000 Oct 01, 7:12 PM
From: JC Sutherland
Date: 2000 Oct 01, 7:12 PM
Paul; You will have no doubt discovered that all the formulas for refraction below 15 deg contain a constant of about 34 min, although in some formulae it is well hidden. If you put the altitude at zero degrees they will all come out to about this value. This begs the question as to where this number comes from? Is it just a fudge to make the numbers come out right or has someone done a some observations to obtain it empirically? My references are unclear about this. Clive
