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: Beginner Meridian Passage Question
    From: Zorbec Legras
    Date: 2004 Sep 3, 11:31 -0500

    ----- Original Message -----
    From: "Noyce, Bill" 
    Date:         Fri, 3 Sep 2004 09:13:03 -0400
    Subject:      Re: Beginner Meridian Passage Question
    > > > b) when you think Polaris is directly below or above the pole, add
    > or
    > > > subtract its difference (which you have memorized as about 45');
    Latitude by pole star.
    Lat = true altitude + corr 1 + corr 2.
    Corr 1 = Pd * Cos LHA
    Corr 2 = ((sqr Pd)/2.3438) * sqr sin LHA * tan true altitude.
    Pd = pole distance = 90 - dec.
    Latitude by meridional transit.
    Upper transit:
    Lat = Zd + dec (1)
    Zd = zenithal distance (= 90? - true altitude).
    + Zd if elevated pole in your back
    - Zd if your are facing elevated pole.
    + dec if same name as latitude
    - dec is diff name.
    Lower transit
    Lat = 180? - (Zd + dec)
    Ex meridian (if you miss the transit)
    Vers meridional Zd = vers (90? - true altitude) - (vers LHA * cos assumed Lat * cos dec)
    with the meridional Zd use formula (1) to compute the Latitude.
    Vers x = versine x = sinus verse x = 1 - cos x
    About the elevated pole, have a dry gin and read it again...
    The elevated pole is the pole in the same hemisphere as the zenith.
    It's hard to be a hero on this planet, one to beam up...
    Sign-up for Ads Free at Mail.com

    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