NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Lunar distances
From: Steven Wepster
Date: 2002 Jan 29, 3:53 AM
From: Steven Wepster
Date: 2002 Jan 29, 3:53 AM
Dear List, I think that the article cited by Trevor is not really suitable as an introduction to lunars. It was written by the staff of HM Almanac Office on the occasion of two centuries of Nautical Almanacs. It presents an "objective assessment of the method of determining longitude by the measurement of lunar distances, in terms of modern knowledge, outlook, notation and computing facilities." [taken from introduction to the article]. There are appended tables of precomputed lunar distances for feb and aug of 1967 and an example calculation. The article also includes a discussion of verious other methods of longitude determination that you may find interesting. However, I have to stress that the lunar distances appended already include semidiameters. This simplifies the calculations a bit but it makes their method and computation harder to compare. It is different from the classical text-books. _Steven. ----------------------------------------------------------- Steven Wepster wepster@math.uu.nl tel +31 30 253 1186 Mathematisch Instituut Universiteit Utrecht PO Box 80.010 3508 TA Utrecht The Netherlands =========================================================== >There is also the paper "A Modern View of Lunar Distances" published in >the Journal of the Institute of Navigation in 1966. (It is pages 131 to >153 of volume 19). I copied it years ago but have never read it. >However, I can confirm that it includes a technical explanation >(peppered with equations), sufficient tables to allow for the clearing >of lunar distances with the data from the Nautical Almanac of the late >1960s (which for all I know may have had data missing from more recent >editions), and a worked example. > > >Trevor Kenchington > > >-- >Trevor J. Kenchington PhD Gadus@iStar.ca >Gadus Associates, Office(902) 889-9250 >R.R.#1, Musquodoboit Harbour, Fax (902) 889-9251 >Nova Scotia B0J 2L0, CANADA Home (902) 889-3555 > > Science Serving the Fisheries > http://home.istar.ca/~gadus