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: Accuracy of sextant observations at sea
    From: Alan S
    Date: 2010 Nov 25, 10:44 -0800

    antoine.m.couette---fr, and others commenting on "the accuracy of sextant observations at sea", the following comes to mind, but first a bit about myself.

    1. I'm not a professional navigator, nor anything even reasonably close thereto, I'm not even a boater. I'm a retired draftsman, sometime field engineer, sometime construction supervisor, who for reasons unknown, became interested in Celestial Navigation, my efforts re the afore mentioned being limited to standing on the beach, shooting whatever might be visible at any given moment, sometimes including the odd bikini clad female, who can be, it turns out, distracting.

    Having said that, and by the way, most of the discussions above referenced, while academically interesting are quite far over my head, the following questions remain.

    1. What sort of boat or vesssel are the sextant shots made from?
    2. Realistically speaking, standing on a smallish boat, a large ship is another story, what sort of accuracy can be reasonably expected?
    3. How experienced is the "shooter"?

    Speaking for myself, standing on a stable platform (the beach), I have obtained two body shots of Sun and Moon, that when reduced and plotted produced fixes within, sometimes well within 5 NM of GPS coordinates. I have also done three body shots, that when reduced and plotted produced fixes that were also within, sometimes well within, 5 NM of GPS coordinates.

    I imagine that such as the above would be sufficiently accurate, however I will leave such judgements in the hands of those more qualified than I, that is those who really know what they are doing.

    Thanks for your patience and attention.

    NavList message boards and member settings: www.fer3.com/NavList
    Members may optionally receive posts by email.
    To cancel email delivery, send a message to NoMail[at]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