Empirical Earth · The Sky — Sun, Moon & Stars
The claim
“Sunset is just the Sun receding and dimming — that explains the dark sky.”
What is measured
Civil, nautical and astronomical twilight are defined by the Sun being 6°, 12° and 18° below the horizon. A receding flat-earth spotlight is always above the plane and can never be any degrees below a horizon, so the entire three-stage framework, and its exact latitude-and-season timings, is a globe signature.
What would show this is wrong
twilight that fails to deepen in three stages tied to the Sun’s depression below the horizon; a Sun measured 18° below the horizon over a flat plane; or twilight durations that ignore latitude and season.
Sources
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