NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Chronometer Suggestions
From: George Huxtable
Date: 2009 Jan 6, 14:57 -0000
From: George Huxtable
Date: 2009 Jan 6, 14:57 -0000
Bill Sellar asked- As a beginning celestial navigator, I am wondering how much time and watch accuracy is actually required for practical navigation. Can we predict how many miles off one would be for every second of time error? ========================== A fair question. Answer: a quarter of a minute of longitude, which corresponds to a quarter of a mile in position-error at the equator, and correspondingly less at highter latitudes. That corresponds to the rate at which the Earth spins, 360� in 24 hours. The precision available from a chronometer ceased to be of any great importance once radio timing signals became available. Bill |Sellar has to realise that many denizens of this list share a quest for precision for its own sake, rather than for the purposes of practical navigation: and who are we to deny them their fun? contact George Huxtable, at george@hux.me.uk or at +44 1865 820222 (from UK, 01865 820222) or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK. --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
