NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Direct methods
From: George Huxtable
Date: 2007 Nov 4, 20:02 -0000
From: George Huxtable
Date: 2007 Nov 4, 20:02 -0000
dw wrote- | Could someone post the equations that are under discussion? These are the equations 7.5a to 7.5f, to be found on pages 78-79 of John Karl's new book "Celestial Navigation in the GPS Age". Best would be for listmembers to obtain their own copy, as I did, as there's a lot of value to be found within its pages ((even if I might have a quibble ot two about some details). I could simply transcribe the equations, but really to make sense they also need the diagram that accompanies, them, at fig. 7.3, which explains the notation. It would be best, then, to scan and post those two pages, if John Karl is listening and will kindly give his consent for me to do so. That may not be a strict legal necessity, for a short extract for comment purposes, but it's polite to ask. In another posting, Gary LaPook referred to the cd covering papers on Celestial Navigation which the ION have put out (and which, I have learned, they have now corrected of some faults and will resend a copy, on request, to anyone who bought the faulty version). "For those of you with the ION cd you will find several papers discussing various ways to compute the fix by direct computation. Look at items 5, 34, 35, 46, 47, 59, 64, 66, 80, 83, and 246. Van Allen,s paper is number 5." Not in my copy of the cd, which may differ from Gary's. Item 5 is indeed a paper on that very topic by, but by Gery, not Van Allen, December 96. It provides a method, in his "step 10", for resolving the ambiguity we have been discussing. A Van Allen paper is no. 34 in that list, printed in Navigation vol. 28 no. 1 (1981), together with several other papers on that same topic. d walden told us that the spreadsheet program came from- "James A. Van Allen, Basic principles of celestial navigation, American Journal of Physics -- November 2004 -- Volume 72, Issue 11, pp. 1418-1424. (Google to find online. Yes, THAT Van Allen!)" which I haven't seen, but am interested in. The procedure in the spreadsheet looks rather different from that described in van Allen's 1981 paper. George. contact George Huxtable at george@huxtable.u-net.com or at +44 1865 820222 (from UK, 01865 820222) or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK. --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---