NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: At the centre of time
From: Douglas Denny
Date: 2009 Oct 21, 02:25 -0700
From: Douglas Denny
Date: 2009 Oct 21, 02:25 -0700
I should have continued with this quote too from:- http://gpsinformation.net/main/greenwich.htm -------- "The Airy Transit's position Comparing the longitude of the Airy Transit in the system available in 1936 to the longitude determined with space techniques gives a difference. Using Ordnance Survey Level 1 Transformation Airy Transit, GB36 = N 51 28 38.265 E 00 00 00.418 Airy Transit, ETRF89 = N 51 28 40.1247 W 00 00 05.3101 X 3980637.8044 Y - 102.4779 Z 4966897.8318 The difference in longitude between the two systems at the Airy Transit is 102.478 metres. Therefore the International Reference Meridian is 102.5 metres east of the Airy Transit at Greenwich. As the IRM is tied to the definition of time the real reference meridian to be used for the Millennium is the IRM which, as shown above, is about 100 metres east of the Greenwich Meridian." -------------- Douglas Denny. Chichester. England. --~--~---------~--~----~------------~-------~--~----~ NavList message boards: www.fer3.com/arc Or post by email to: NavList@fer3.com To , email NavList+@fer3.com -~----------~----~----~----~------~----~------~--~---