A thoughtful look at objects visible beyond what the calculated dimensions of earth should call for, being (8 inches per mile squared if 10253.13 miles at the diameter), gives us a drop off that is a mismatch for what we actually see, & can explain w/ perspective & opacity at distances. Zoom cameras can retrieve boats & such, w/ water beyond them, when thought “over the curve,” showing it’s a limitation of our eyes & the inevitable clouding by the thickest atmosphere at sea level.
A lighthouse minimum is 13 feet, so we’ll be generous & create a 100 footer which by 15 miles should be well past the ball’s drop-off, so let’s see if there are photos at that distance…
This proved challenging, so I gathered stats instead: (Guinness World Records)
The brightest lighthouses in Europe and Africa, respectively, are Créac’h Lighthouse in Ouessant, Finistère, France, and the “new” Cape Point Lighthouse in South Africa, both of which are said to be visible 60 km (32.5 nautical miles; 37.3 miles) out at sea.
That’s 927.81 feet of curvature at 37.3 miles.
A thought when standing in front of Lake Michigan: “It looks like an ocean.“
