Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
       
    Reply
    Re: averaging devices on sextants
    From: Alexandre Eremenko
    Date: 2004 Oct 8, 09:06 -0500

    Thank you to all for interesting information in reply
    to "Averaging". There is one point on which I think additional
    comment is necessary:
    
    On Thu, 7 Oct 2004, Ken Gebhart wrote:
    
    > The idea of averaging sextant readings using a marine sextant,
    > (ie. instead
    > of using a bubble), really has no basis because acceleration
    > has no effect
    > on it.
    
    The procedure of averaging observations using a marine sextant
    is recommended by many books and manuals, from XVIII century
    to these days.
    It is not specific to bubble horizons or effects of acceleration.
    It is also used on land.
    
    The purpose of this procedure is to increase precision.
    In fact this is a standard procedure increasing accuracy of
    ANY scientific measurements.
    The theoretical foundation of this procedure lies in
    the "Method of Least Squares" by Gauss. The most
    comprehensive discussion
    in the context of practical astronomy
    of this theoretical basis is contained in the last chapter of
    Chauvenet's 2-nd volume.
    
    The specific of aerial observations is that the random error
    coming from acceleration is very large, and the averaging has
    to be done quickly. That's why they have a built-in mechanism,
    integrator, that does it automatically.
    
    Alex.
    
    
    

       
    Reply
    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