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

The four mirages — and why refraction never repeals the curve

The claim

“I can see a city/ship that curvature says should be hidden — refraction proves the curve isn’t there.”

What is measured

Mirages don’t abolish the curve. They trace it. Light bends toward denser air, which near a cold surface means bending downward, following the globe. That is why over-horizon sightings are sporadic, distorted and tied to inversions, and why the same physics in its mild everyday form is baked as a fixed 7/6 correction into every survey and nautical almanac.

What would show this is wrong

Watch one target across cold water at dawn and dusk over several days. A flat plane predicts a steady, full-height image that only shrinks with distance. Instead the target rises, sinks, stretches, inverts and splits into bands as the temperature profile changes, and in ordinary air it vanishes from the waterline up. Those changes track the measured lapse rate, not the observer’s wishes.

Sources

  1. Mirage types. Inferior, superior, towering and stooping mirages, and the Fata Morgana. Wikipedia: Mirage link
  2. Atmospheric refraction & ducting. Refractivity N = (n−1)×10⁶, the ~−40 N-units/km standard gradient, the effective-Earth-radius factor, and the −157 N-units/km trapping threshold. Resonance link
  3. Novaya Zemlya effect. Polar ducting that raises the Sun into view while it is geometrically below the horizon; first recorded by Barents’ crew, January 1597. Wikipedia: Novaya Zemlya effect link
  4. The standard coefficient of terrestrial refraction. Gauss measured the coefficient near Hannover at k ≈ 0.13; surveyors model the effect as an enlarged effective Earth radius R′ = R/(1−k) (t link
  5. Rise, set and twilight definitions (U.S. Naval Observatory). The standard sunrise and sunset definition places the Sun’s center 50 arcminutes below the horizontal, combining 34 arcminutes (0 link
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