NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: sight reduction tables
From: Doug Royer
Date: 2007 Sep 28, 15:52 -0700
From: Doug Royer
Date: 2007 Sep 28, 15:52 -0700
How does HO allow, for its named stars, for the slow drift in star position caused by precession? Is there some way provided of correcting for this drift, year on year? Or is Vol 1 of HO249 reissued after a period, when precession starts to put star positions unacceptably far out? In the opening pages of Vol #1, HO 249 there is correction instructions for nutation and procession. Each printing of Vol 1, HO 249 is only really meant to be used for 5 years from the print date. --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
