Welcome to the NavList Message Boards.


A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Add Images & Files
    Re: Long Term vs Annual Almanac
    From: Hewitt Schlereth
    Date: 2015 Nov 30, 10:13 -0800
    Mark, if you happen to have a Nautical Almanac that is four years out of date, it's good for the sun and stars. Thus, four consecutive years of almanacs = long term almanac, depending on the precision you want.

    For practical purposes, the sun data is good for 20 years if you can accept an imprecision - after the 5 cycles - of 3' in declination and 1' in GHA.

    For stars you have to add 1.84' per 4-year cycle to Aries.

    If you have Vol. 2 of the 1972 green Bowditch there is a three page long-term almanac in its appendix.

    It sounds like the long-term almanac you refer to is Geoffrey Kolbe's. It's higher precision, is easy to use, and is quite compact. He's an active member of this forum.NavList. 


    On Nov 30, 2015, at 8:35 AM, Mark Coady <NoReply_MarkCoady@fer3.com> wrote:

    It has been a December tradition for me to pick up the Nautical Almanac for the next year (and Eldridges for tides,  Merry xmas to me,LOL).  I Prefer the hardcover for nostalgic reasons of real books, but usually pick up the Blue Softcover Commercial edition, readily available at local haunts like West Marine, Landfall, and Defender.

    I noticed prowling Amazon the other day there is a long term Alamanac, hypothetically good till 2050.  Which exceeds my probable life span.

    I assume that it is an Almanac with corrections, such as we might do if faced with using an expired almanac a year or two old in an emergency.

    Am i right?, does this add a step and yet a new place for possible distracted error? is it worth my while?  I am kind of fond of the tradition of my New Almanac each year for reasons of emotion not logic. 

    The Long Term Almanac is attractive, for reasons of cost, and a sense that I'm always prepared.

    I can see an advantage to the boat world traveler who might have reason to get several years ahead, but to me, who is tied to the East Coast for the moment, it hardly seems a worry. 

    View and reply to this message

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.

    Email Settings

    Posting Code:

    Custom Index

    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site