Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Position-Finding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
    Re: Longhand Sight Reduction
    From: Lars Bergman
    Date: 2014 Nov 26, 13:35 -0800

    Hanno Ix wrote "here is a simple equation for the azimuth Z".

    Simple? Not for longhand calculation according to me, with multiplication, division and squaring.

    A more simple formula, similar to the one used for finding altitude, is this:

    N = hav(latitude - altitude)

    P = hav(latitude + altitude)

    Q = N + P

    hav(Z) = (hav(polar distance) - N) / (1-Q)

    where polar distance = 90° - declination (if lat and dec are of same name; otherwise 90° + declination).

    The difficult part is the division with (1-Q), for very small values of Q this could be replaced by a multiplication with (1+Q).

     

    Lars 59N 18E

     

    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    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:

    Email Settings

    Posting Code:

    Custom Index

    Subject:
    Author:
    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