American Woodhenge: Archaeoastronomy at Cahokia

Abstract

This paper examines the post-circle monuments at Cahokia for astronomical alignments other than the already well-established solar alignments. Using data from previous studies and photographs taken at Cahokia, the woodhenge is reconstructed in the virtual sky feature of an astronomy software program, TheSky6. Then using data from previous archaeoastronomy studies, and historical and ethnographical sources, the Pleiades and the moon are examined as potential targets for observation. The Pleiades, which makes its first appearance over one of the woodhendge posts, was significant in cultures worldwide and may have had special significance int he agricultural calendar at Cahokia. New moon observations suggest that the woodhenge may have been used to track the lunar calendar and to bring the solar and lunar years into alignment.