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: Photo sextant sights
    From: Andr�s Ruiz
    Date: 2008 Jul 30, 15:37 +0200

    See also: 
    De: NavList@fer3.com [mailto:NavList@fer3.com] En nombre de Wolfgang K�berer
    Enviado el: mi�rcoles, 30 de julio de 2008 15:16
    Para: NavList@fer3.com
    Asunto: [NavList 5950] Photo sextant sights
    Yesterday I received "The Navigator's Newsletter" issue 97 - 99. The last 
    issue contains an article by David Burch (from his book "Emergency 
    navigation") about "Photo sextant sights". As this had been discussed on the 
    list not too long ago I read the article right away. It relates the example 
    of a "Photo sextant sight" taken in Florida at 27deg 12,2 min N, 80 deg 13,4 
    min W.
    Now being in the legal profession I lack the knowledge or the brains (or both) 
    to invent new methods of celestial navigation, but like to try their 
    practical usefulness. The article sums up: "had we not known time or 
    longitude, we would have found our longitude this way to within 53 min ". 
    This would mean a possible error of about 47 miles - which is probably 
    Then I did a quick "Sumner": I varied the input to see what happens to the 
    result. On the assumption that there is no error in latitude (having bent my 
    sextant only after taking the height of Polaris or a star on the meridian) 
    and that my time is correct, I varied my assumed longitude and got a 
    perplexing result: Using Frank's program and assuming I am about 150 miles 
    out in the Atlantic (= assumed longitude 77deg 10 min W) I got the following 
    "Error in Lunar: 0 min
    Approximate Error in Longitude: 0 deg 00.4 min"
    which - following David Burch - I interpret as saying I am almost at my 
    assumed position. As the "Photo Sextant Sight" supposedly was taken 3 degrees 
    further west something doesn't fit. What did I get wrong? It's not the input, 
    I checked it several times.
    Dr. Wolfgang K�berer
    Wolfsgangstr. 92
    D-60322 Frankfurt am Main
    Tel: + 49 69 95520851
    Fax: + 49 69 558400
    e-mail: koeberer@navigationsgeschichte.de
    Navigation List archive: www.fer3.com/arc
    To post, email NavList@fer3.com
    To unsubscribe, email NavList-unsubscribe@fer3.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