NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Navigation exercise
From: Bill B
Date: 2008 May 19, 04:29 -0400
From: Bill B
Date: 2008 May 19, 04:29 -0400
> I computed LAN= 12h 9m 42s by the equation of time method. What am I doing > wrong? I apologize any overkill in the last post. Walk before you run ;-) To figure the equation of time for any given UT hour, look at the difference between the GHA and mean GHA. For the Sun, mean GHA would be multiples of 15d increments on the hour with 12:00:00 UT being 0d 00!0. Convert the difference between the actual GHA and mean/theoretical from arc to time, noting fast or slow. For example, the mean 12:00:00 GHA for the Sun (prime meridian) should be 0d 00!0 and the published GHA is 1d 00!0 you know intuitively the Sun got there ahead of schedule. Convert arc to time and you have the equation of time. In this case 1d = 4 minutes of time. That's a bit simplistic in the scope of the universe, but for practical cel nav purposes it works. At least for me ;-) Bill --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
