NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Accuracy of ephemeris
From: John D. Howard
Date: 2017 Oct 16, 07:02 -0700
From: John D. Howard
Date: 2017 Oct 16, 07:02 -0700
Bill,
The "Gold Standard" is the data put out by the Jet Propulsion Lab. They have a public website called Horizions that you can access ( some of ) their data.
The limit on cel nav ( IMHO ) is time. We only record our time to the second and the Nautical Almanac only shows data to the second but that is .25 minutes of arc. Untill we record the sight to the hunderth or even the thousands of a second we canot get better than .25 MOA - hard to do using a hand held sextant.
John H.
