The Longest Sightline on Earth
See, all the examples above are limited by the curvature of the earth, and that is why the horizon seems to be the limiting factor. But there are two additional variables in play that can allow for some truly amazing sightlines: the height of the target and the temperature of the air. The height of the target is intuitively obvious, as we all realize we can see Calgary's skyline from way further away than 4.7 km. In fact, Calgary's skyline can be seen at least 50 km away since the height of the