NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: mid-longitude sailing
From: Dan Allen
Date: 2007 Jan 7, 17:53 -0700
From: Dan Allen
Date: 2007 Jan 7, 17:53 -0700
On 7 Jan 2007, at 11:58 AM, George Huxtable wrote: > Consider a great-circle journey, from (lat1, long1) to (lat2, long2). > What's the latitude, at the mid-longitude point, where the long is > (long1 + long2) / 2 ? > > It's given by the simple expression tan lat3 = (tan (lat1) + tan > (lat2)) / 2 cos ((long2-long1)/2) I have not seen that formulation before. Thanks George! That is almost simple enough to remember... Dan --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
