A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Tony Oz
Date: 2018 Jan 18, 06:28 -0800
You wondered if solar GP on a solstice was different 5000 years ago.
My take on it is this: if we use a landmark as an aim of a sunrise/sunset point (azimuth) at a solstice - then it stays the same (allowing for the obliquity of ecliptic change, which is not that big). So, referring to the Stonehendge pillars, the ancient structure should be usable today.
The story is completely different if you were using stars for noticing when a solstice is nearing (by looking which stars do rise/set at the dusk/dawn), the stars sphere would certainly be in a different position 5000 years ago.