Shadow-Based Chronolocation

1. 1. Geolocate first (6.4.1). Without lat/long, solar position cannot be calculated.

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2. 2. Identify vertical object with a sharp projected shadow. Pole, column, standing person.

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3. 3. Measure cardinal direction of the shadow (azimuth in degrees from Google Earth Pro).

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4. 4. Measure relative length: ratio shadow/object_height. Solar elevation = arctan(h/l).

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5. 5. Compute solar position with SunCalc.org (move slider until azimuth+elevation match).

   SunCalc.org ↗

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6. 6. Resolve symmetric date ambiguity with contextual clues (vegetation, snow, datable events).

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7. 7. Validate with historical weather. Visual Crossing Weather History (free tier).

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8. 8. Document margin of error. Typically ±30-90 min of time, ±2-7 days of date. Report with confidence level.

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