ObjID502-1
‹ Ancient Sundials
Dialface ID 545
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Abstract
Information on the Dialface ID 545 / Object ID 502
Measurements
Measurement record: pipeline ObjID 502, matched to this dialface by inventory number.
| Quality grade | B (completeness 96 %) |
|---|---|
| Dial surface | sphere (decisive) · fit residual mm: cone 5.04, cylinder 5.78, sphere 0.96 |
| Latitude φ | 43.05 ± 2.48° (consensus of witnesses) |
| Klima | Massalia, Rome, Mid-Pontus (VI) |
| Engraved lines | 11 hour lines, 3 day lines |
| Cone half-angle α | not shown: surface fit decisively sphere: cone-specific quantities do not apply |
| Measured | 2026-06-12 20:51 |
What the dial shows at this latitude
| Winter solstice | Equinox | Summer solstice | |
|---|---|---|---|
| Noon altitude of the Sun | 23.2° | 47.0° | 70.7° |
| Noon shadow (gnomon heights) | 2.33 | 0.93 | 0.35 |
| Length of the day | 8.8 h | 12.0 h | 15.2 h |
| Length of a seasonal hour | 44 min | 60 min | 76 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
