The Great Pyramid has a subtle concavity (~0.92m) on each face, creating 8 sub-faces. Twice a year at the equinoxes, sunlight bisects each face along this concavity — visible only because of the sun's specific angle at Giza's latitude.
Globe: Parallel rays. Noon elev = 60.02°. Shadow = 84.6m. Sun sets at HA=±90°.
Flat: Sun at 5,000km over equator. Noon elev = 56.3°. Shadow = 97.7m. 13.1m difference — easily measured. Sun never sets.
| 0.126 | 0.162 | 0.216 | 0.261 | 0.612 | 0.621 |
| 1.26 | 1.62 | 2.16 | 2.61 | 6.12 | 6.21 |
| 12.6 | 16.2 | 21.6 | 26.1 | 61.2 | 62.1 |
Giza latitude 29.9792°N — digits match the speed of light: 299,792 km/s. The Synergy Grid permutations of 1,2,6 map to the pyramid's concavity star pattern.