I explore the evidence for astronomy at the Neolithic passage-grave of Knowth in the Journal of Lithic Studies (University of Edinburgh).
The article is here.
Knowth has two passages with entrances at the east and west. In addition to analysing the available survey evidence, kerbstone engravings are interpreted as depicting astronomical cycles.
It is argued that, while Knowth’s passages function in relation to the equinoxes, they are not internally orientated to match exactly the equinoctial directions. Rather, it seems that they may have been constructed and used to facilitate the harmonisation of the solar and lunar cycles - much in the same way as does the equinoctial Judeo-Christian festival of Easter.