On the solstices, during the noon and midnight hour, the orbital pole aligns with the celestial pole due north, this creates the same upper sky as during the rising or setting sun on the day of the equinoxes.
When both the orbital and celestial poles align at maximum tilt we can approximate the midnight hour by referring to the star that lies closest to the meridian that holds the zenith point on the ecliptic plane. This star should not be confused with a pole star which is defined by its proximity to the axis of rotation. For the ‘meridian star’, for lack of a better term, any latitude will do.
The idea of using meridian stars could have been much older than Dynastic Egypt or even Predynastic Egypt (c. 6000 BCE). Read more...
