A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Fleming
Date: 2015 Oct 19, 14:34 -0700
The differenc is the difference between solar time and sideral time. Which is to say that as the sun is near it position changes with both rotation of the earth and orbital motion of the earth about the sun (parallax). while the first point of aries is infinitely far away so only changes position due to rotation and suffers no parallax do to movement of the earth about the sun.