The number of miles is not the relevant number. It's the angle that matters. The angle is determine by the relative lengths of two sides of the right triangle. Get a protractor or download an app of some sort and measure 8° above the horizon and see for yourself how far it is.
It's isn't minuscule but it still rather small. It's not quite 1/11th of the way to the highest point in the sky. Certainly noticeable if you're looking for it and easily missed if you're not.
Incidentally, there would be no drop in the horizon at all if the Earth were flat. In fact, on a flat Earth there would not be any hard horizon line. Presuming there was nothing in the way, you should be able to see all the way to the "Ice Wall" with just a little help from even a modest telescope. Of course there are variables like Rayleigh scattering and other atmospheric effects that would obscure the view of distance objects but the point is that there wouldn't really be a horizon in the sense we are used to thinking of it. Things would just sort of fade into a haze in the distance rather than there ever being a hard horizon line like there is here in the real world.
In essence, every time you acknowledge that there is a horizon, you tacitly accept that the Earth is not flat.
Clete
Metabunk
Distance in Miles: 229.2 Viewer height in Feet: 35000
Results ignoring refraction
Horizon = 229.2 Miles (1210153.46 Feet)
Bulge = 1.66 Miles (8759.49 Feet)
Drop = 6.64 Miles (35060.01 Feet)
Hidden= 0 Feet (0 Inches)
Horizon Dip = 3.313 Degrees
Right Angle Triangle Calculator
Given A=13.2 and B=229.2
C = 229.58, ∠A = 3.3°, ∠B = 86.7°
Side A = 229.2 miles distance
∠A = 3.3°
View attachment 26561 Side B = 13.2 miles height
These two websites agree on the angle. So at least I have the math figured out in both distance and angle, thanks.
"Things would just sort of fade into a haze in the distance rather than there ever being a hard horizon line like there is here in the real world. In essence, every time you acknowledge that there is a horizon, you tacitly accept that the Earth is not flat." --Clete
But, flat earth would argue, since the horizon dip is so miniscule the horizon is virtually at eye level, there's no looking down that we can detect. If the horizon seems at eye level and the drop is undetectable then I have no visual evidence that the earth is curved.
So, every time we see a "hard horizon line" we know the Earth is not flat. Does this mean that if there are times when we see "things just sort of fade into a haze in the distance" the earth is flat?
--Dave