A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2017 Dec 17, 14:42 -0800
The NA data is based on light that hits the retina of the observer on the surface of Earth and so declination and hour angles will repeat no matter whether from the Moon or a star 500 light years away. As for GPS it is a different story. I'll pass it on to the better informed to explain the satellite stuff.