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
    Two Bodies + Angle Between Them = Third LoP
    From: David Iwancio
    Date: 2020 Feb 17, 11:10 -0800

    Before I expend more mental energy on this idea, I'd like to know if this has been done before so I can avoid re-inventing the wheel. 

    A brief outline:

    • Altitudes of two stars give standard two-body fix
    • Sextant distance between two stars + lunar distance-style math = high-precision difference in azimuth between two stars
    • Difference in azimuth is analagous to horizontal angle between two objects in coastal piloting
    • Can be used to produce "circle of equal angle" (see Bowditch 2019, section 1102)

    Unlike the two circles of equal altitude, this third LoP would be relatively insensitive to any non-standard dip and should be immune to any failure to swing the sextant properly.

    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