MYS0D9KTB707Q8J·Mystery · site
The great houses of Chaco Canyon
Summer solsticeOne dagger through the centre of the large spiral, near midday.
EquinoxesA dagger through the small spiral, and a second through the large one, right of centre.
Winter solsticeTwo daggers frame the large spiral, one at each edge.
Moon, major standstillThe moonrise shadow's edge touches the left edge of the large spiral.
Moon, minor standstillThe moonrise shadow's edge crosses the centre of the large spiral.
Our diagram, drawn from Sofaer, Zinser and Sinclair (1979) and Sofaer, Sinclair and Doggett (1982). Not to scale. The panel has been closed to visitors since the 1980s, and the middle slab has shifted since 1989.