Aligned to the Heavens

Many ancient earthworks appear to have been designed to align with the movements of the sun and the moon. It may be that such special astronomical events as solstices or lunar standstills determined when ceremonies were held at these sacred complexes.

The Newark Earthworks and High Bank Works, though they are 60 miles apart, show remarkably similar designs. Both have a 20 acre circle attached to an octagon. Because Newark Octagon is still intact, archaeastronomers have been able to prove that it is aligned to the movements of the moon. The moon moves through a complicated 18.6 year cycle called the “lunar standstill cycle.” In this cycle, there are four moonset points and four moonrise points. The Newark Octagon is aligned to all eight of these lunar standstill points.

High Bank Works, part of Hopewell Culture National Historical Park, was not so fortunate in its treatment over the last two centuries.  The once 10 foot high walls of the High Bank Octagon are now only barely visible undulations in a former farm field. However, they are visible with LiDAR. Archaeastronomers Dr. Ray Hively and Dr. Robert Horn theorize that this octagon is not only aligned to the lunar standstill cycle, but the solstices as well. The below diagrams show their theoretical alignments on Squier and Davis maps that have been modified according to the results of the 1892 survey by Cyrus Thomas and James Middleton.

Lunar Standstill Alignments at High Banks Works.

Solstice Alignments at High Banks Works.

Many of the alignments are sited through gateways in High Bank Works’ earthen walls. Apparent irregularities in the geometric deisgn of the earthworks could be the result of an architectural plan that encompassed both artistic symmetry and astromonical alignments:

  • The octogon’s southern gateway is not located at the corner of the octagon like all the other gateways. This design element may have allowed for an alignment to the minimum south moonset to the southwest.
  • No gateway exists on the southwest gateway of the octagon. This design may have emphasized the importance of the maximum north moonrise point to the northeast. This point apparently defined the main axis of the very similar circle and octagon complex in the Newark Earthworks.
  • A seemingly random gateway in the southeast wall of High Bank Works’ great circle allows for an alignment to the winter solstice sunrise from the apex of the circle that touches the north corner of the octagon.

The more distant the two points of an alignment are, the more accurate it may be. The desire to make accurate astronomical alignments has been proposed as one reason the Hopewell may have designed their earthworks so large.