Evidence
fact ⇄ what kind of claim · live
Light bends toward denser, colder air; curvature rides on dT/dz
N = 79 P/T, rays follow y'' = 10⁻⁶ dM/dz · textbook optics
MEASURED
An inversion near +0.11 K/m curves light as fast as Earth curves away
the duct threshold, recomputed live from your dials
MEASURED
1597: the sun back two weeks early over Novaya Zemlya
de Veer's journal; ray-traced closed in 2003, one inversion fits all
REPORTED
Min Min lights reproduced with car headlights 10 km beyond a rise
Pettigrew 2003 · six witnesses watched them float
MEASURED
Marfa lights tracked US-67 traffic; a headlight flash made one on cue
UT Dallas SPS field study, May 2004
MEASURED
Mirage images stay within about 1° of the horizon; range D ≈ 500 H
Viezee's survey for the Condon Report, 1969
REPORTED
The century's most famous mirage photo was a plate of Bristol, England
Willoughby's Silent City, 1889 · the cautionary card
REPORTED
Whether any given sighting was a duct is a per-case reading
the bench computes the bounds; the file stays open
READING
View
The straita computed picture
The ray benchprofiles and fan
The image machineone curve, all images
The file1597-2004
Scene
Standard airthe baseline
Cold straitthe Fata Morgana
Hot desertthe inferior mirage
Night ductthe floating lights
…
Display
Shimmerthe layer breathing, MODELLED
True-scene insetthe same view with no atmosphere
No-atmosphere referencedashed line in the fan and the curve
Readout · live from the tracer
Scene in force
…
Peak dT/dz
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Duct threshold
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Ray curvature
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Images of target
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Angular window
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Earth drop at range
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…
What is measured vs modelled here
Measured: the refraction formula N = 79 P/T, the ray equation, the duct threshold, the Earth-bulge geometry, and the two field reproductions (Min Min 2003, Marfa 2004). Reported: de Veer's 1597 journal, the Messina record, the Silent City hoax, and Viezee's survey limits for the Condon Report. Modelled: the ship, shoreline, town-light and dune silhouettes, the smooth analytic temperature profile, and the shimmer. Reading: whether any particular sighting in any particular file was ducted light. The bench computes the bounds and stops there.
The ray model
The optical refractivity is N = 79 P/T (no water-vapour term in the optical band, the one honest difference from the radio formula in INST-30). The flat-Earth transform adds the bulge: M(z) = N(z) + 0.157 z, and every ray integrates y'' = 10⁻⁶ dM/dz in 30 m steps from your eye to the target. The picture is built by tracing one ray per screen row and painting back whatever that ray lands on: sea, silhouette, or sky. Nothing in the scene view is drawn by hand.
Where this drawing takes liberties
The temperature profile is a smooth analytic curve, not a radiosonde; real ducts are patchier and the images accordingly messier. The shimmer is cosmetic noise standing in for turbulence, tagged MODELLED. The silhouettes are drawings. The scene compresses colour and brightness for a screen. The formulas, the threshold, the transfer curve and the case quotations take no liberties.
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