Quote:
Originally Posted by SAUGUS BOATER
Actually,
Iron fish and Rattlesnake guy's formulas are both incorrect as neither takes into account the refraction constant. While the earths curvature makes the horizon appear slightly higher, the light moving through the earths atmosphere makes the horizon look slightly lower. I am a land surveyor and must make both corrections to every distance I measure (although my instrument makes these calculations so there is no need for tedious formulas !!)  |
They are
not incorrect. They are approximations. The complete explanation of the approximations has not been provided. They could be explained -- but I doubt this FORUM is the place to do so.
But it's true that refraction is one of the things left out. Another thing left out is the complete Pythagorean formula. That was done because of the relative difference between the Earth's Diameter (7,900+ miles) and the height (46 feet) of the observers. In addition, the Earth's diameter is not the same at every point on Earth -- so we only used an average. But each of these things have a minor computational effect on the final answer. We're interested in whether the answer is 46 feet or 102 feet -- not whether it's 46 ft or 46.3 ft.
So I think it's a stretch to come in and say "
these calculations are incorrect". They're a damn good approximation -- and that's all we're looking for here on the FORUM, I believe.