Looks like hit has to be, because I found this:

I found this in the FAQ

Q: "Please explain sunrises and sunsets."

A: It is a perspective effect. The sun is just getting farther away: it looks like it is disappearing because everything gets smaller, and eventually disappears as it gets farther away.

which would also require bendy light to explain.

Firstly, I have observed the sun to not appear to get smaller before sunset.

Secondly, lets look at the geometry of the situation: Lets determine where I should observe the sun to be at midnight. I live in Ottawa, Canada, which lies roughly halfway between the north pole and the equator, a distance equalling an eighth of the diameter of Flat Earth. In the same FAQ post, the diameter of flat earth is defined as being 24900 miles, this means I live 3112.5 miles from the north pole (assuming I'm precisely at the halfway point). To get the total horizontal distance between me and the sun at midnight, we add half the earth's radius (because the sun revolves along the equator, halfway along the radius), to the distance between me and the north pole:

12450 miles + 3112.5 miles = 15562.5 miles horizontal distance between me and the sun at midnight.

Now let's consider the vertical distance between the ground and the sun. The FAQ states this as being 3000 miles. Now we can construct a virtual right triangle, with a base of 15562.5 miles, and the height 3000 miles. We can now use trigonometry to determine the angle of incidence for the sun. this can be used using the formula tan(angle) = opposite side / adjacent side

tan(angle) = 3000 miles / 15562.5 miles

angle = tan

^{-1}(3000/15562.5)

angle = 10 (Edit: 10.91 which rounds to 11. My mistake)