What isn't mentioned in Zecharia Sitchins book is why we don't know exactly what made the solstices so important. Cosmic code goes on to involve an exterrestrial race called the Annukai. I don't know about them but Sitchin makes very many correlation's between language, names and myth and may very well be onto something.
What is certain is that focusing on exactly what we don't know brings a point that corroborates inferentially what I propose as the missing knowledge of the old world. If the old world did contain most of its information in the minds of the bearers of oral histories and something made them unable to be conscious of the past carried in their unconscious, then we wouldn't have anything tangible to inform us of why the stone shrines align with the solstices surround our planet except the stone shrine.
How many degrees?
The last paragraph refers to "Tiwanaka", ruins on the shores of Lake Titicaca. The conclusion that the cairn solar center was a burial chamber doesn't fit the constant open air use format of stonehenge. The great Pyramid has a shaft that allows light to reach the Pharaohs chamber on summer Solstice.
The eyes, once adjusted to the darkness, can be used to make a photo imprint temporally. There are potentials for knowledge stored in our genes to be activated as an evolutionary mechanism with exposure to light and conditions as catharsis.