ObjID410-1
‹ Ancient Sundials
Dialface ID 449
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Abstract
Information on the Dialface ID 449 / Object ID 410
Measurements
Measurement record: pipeline ObjID 410, matched to this dialface by inventory number.
| Quality grade | A (completeness 96 %) |
|---|---|
| Dial surface | cone (preferred, not decisive) · fit residual mm: cone 0.96, cylinder 1.33, sphere 6.31 |
| Latitude φ | 19.97 ± 1.53° (single witness: hours-SuSo-regression) |
| Engraved lines | 11 hour lines, 3 day lines |
| Cone half-angle α | 15.0 ± 0.29° (cone residual on all points 1.06 mm) |
| Measured | 2026-06-12 20:46 |
What the dial shows at this latitude
| Winter solstice | Equinox | Summer solstice | |
|---|---|---|---|
| Noon altitude of the Sun | 46.3° | 70.0° | 86.3° |
| Noon shadow (gnomon heights) | 0.95 | 0.36 | 0.07 |
| Length of the day | 10.8 h | 12.0 h | 13.2 h |
| Length of a seasonal hour | 54 min | 60 min | 66 min |
Computed for the measured latitude with the obliquity of the JPL ephemeris at 101 BC (year -100). The latitude is the one the dial was made for, not a find-spot coordinate.
References
3D Models
