Bobby 🇺🇸 :
Common misconceptions that make it seem “not true”:
• It doesn’t mean you can’t see 10 miles away. The drop is from a tangent line, not the line of sight between two elevated points. Both observer and target have height (eyes, hills, towers, etc.), so the “hidden” amount is less. You also get atmospheric refraction, which bends light and lets you see farther.
• It’s not a constant slope — it’s a curve, so the effect accelerates with distance (squared term).
• Real observations match the globe: Ships disappear hull-first over the horizon. Distant landmarks or skylines show partial hiding consistent with curvature (after accounting for height and refraction). Long bridges, laser tests over water, and high-altitude photos all align with expected curvature, not a flat plane.
• For very precise work, better formulas exist (like h ≈ d² / (2R) or using cosine), but the 8”/mile² is a solid quick estimate.
If you’re looking across 10 miles of flat water from eye level (~6 ft), the horizon is much closer than 10 miles, and distant objects will have their bases obscured — exactly as predicted. People often expect to see a massive “hump” or total blockage that isn’t how spherical geometry works.
This claim appears a lot in flat Earth arguments (e.g., “We can see across lakes that should have 66 ft of drop!”), but it overlooks observer/target height and refraction. The globe model holds up under scrutiny with the right math and observations.
2026-05-08 04:17:13