NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Almanacs, theory and use.
From: Paul Hirose
Date: 2007 Nov 20, 12:04 -0800
From: Paul Hirose
Date: 2007 Nov 20, 12:04 -0800
Basically, the figures tabulated in the Nautical Almanac are the *geocentric* positions of celestial bodies, i.e., their positions as seen by an imaginary observer at the center of a transparent Earth. Calculating their positions for a particular place requires another book: a "sight reduction" table. A detailed description of the nautical almanac can be found in "The American Practical Navigator". The book is usually just called "Bowditch", after the name of the original author. Take a look at chapters 19 and 20 in the online version: http://www.i-DEADLINK-com/bowditch/ Chapter 19 is devoted to almanacs, but to see images of actual almanac pages you have to look in chapter 20! Note that Bowditch is a reference manual, not a textbook, so for a novice it can be overwhelming. It's not the easiest way to learn celestial nav. -- I block messages that contain attachments or HTML. --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
