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Re: Refraction formulas
From: Victor Reijs
Date: 2000 Sep 28, 12:04 PM
From: Victor Reijs
Date: 2000 Sep 28, 12:04 PM
Hello Henning,
I also have a formuae available on the web (using Javscript):
http://geniet.mypage.org/refract.htm
All the best,
Victor
Henning Umland wrote:
>
> In addition to Bennett's formula, Meeus quotes Smart's formula:
>
> R['] = 0.9716*tan(90-H) - 0.0011*(tan(90-H))**3
>
> H is stated in degrees.
>
> According to Meeus, the formula gives accurate results between 15� and 90�.
> At 90�, R becomes 0. I checked the formula repeatedly and found that even at
> 10� altitude, the results are accurate enough for navigational purposes.
>
> Henning Umland
> h.umland@online.de
> www.umland.onlinehome.de
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