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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Refraction formulas
From: Henning Umland
Date: 2000 Sep 28, 7:03 AM
From: Henning Umland
Date: 2000 Sep 28, 7:03 AM
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