The star shape on the gnomon casts a shadow allowing us to mark specific points in the yearly solar cycle. I already had a mark for the Summer Solstice solar zenith, and wanted to catch the shadow at Winter Solstice zenith as well.

The day didn’t look promising—lots of rain and low clouds. But just a few minutes past zenith time, the clouds zipped open. Close enough!

I was tickled to see that the yellowlegs (the bird to the right of the shadow) just happens to be pointing its beak directly at Winter Solstice zenith.