Sighting the Sun — and moon? — at Stonehenge

The connection between Stonehenge and summer solstice sunrise is well known, but decades of overspeculation, by both astronomers and archaeologists, concerning the use of the monument for observations of the sky have led many to steer well clear of the subject. In the first part of this talk I will describe what we can sensibly say about the relationship of Stonehenge to the sun, how this relates to more conventional archaeological evidence that has been uncovered in recent years, and what it might have meant to the people who built and used Stonehenge.

But what about the moon? We have just passed a major lunar standstill, an event occurring every 18.6 years around which time the moon can be seen at fortnightly intervals exceptionally far to the north and south. Was this -- as some have suggested -- known to our prehistoric forebears and was it marked and celebrated, along with the sun and the seasons, at Stonehenge and elsewhere?

I will describe some of the challenges in exploring these questions and what we can conclude with reasonable confidence about the cultural significance of the sun and moon to those who built and used Stonehenge.