Empirical Earth · The Boomerangs — Flat-Earth Proofs That Backfire

Lighthouse ranges are computed from the curve

The claim

“Lighthouses are visible from too far away for a curved Earth.”

What is measured

A Light List’s geographic range is pure curvature geometry: distance to the horizon ≈ 1.17 × √(height in feet). A 100-foot light seen from 15 feet up has a geographic range of ~16 nautical miles. Raise the observer and it grows, just as a sphere predicts.

What would show this is wrong

a Light List that omits the geographic (curvature) range; lighthouse ranges that fail to grow with observer height; or rising/dipping distances that don’t match √(height) curvature math.

Sources

  1. Geographic vs luminous range — and the loom. A light’s geographic range is set by Earth’s curvature and the heights of light and observer (a 100-ft light, 15-ft eye → ~16 nm); the loom is up link
  2. The distance-to-horizon formula & Light Lists. Distance to the horizon (nm) ≈ 1.17 × √(height in feet); geographic range is the light’s horizon distance plus the observer’s, tabulated in the link
  3. The geographic range of a light, and where its constant comes from. A Light List gives two ranges for every light: a luminous (nominal) range set by the intensity of the light, and a geograp link
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