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: Position discrepancy
    From: Derrick Young
    Date: 2011 Dec 13, 15:03 -0500

    You need to look at which earth model is being used for the Almanac, Henning’s, the online almanacs as well as your GPS.  The variation of several nautical miles is not unusual with the different models.


    Derrick Young


    804-734-8000, x48561



    Our virtues and our failings are inseparable, like force and matter. When they separate, man is no more." --Nikola Tesla, Austrian-American inventor and engineer


    From: navlist-bounce@fer3.com [mailto:navlist-bounce@fer3.com] On Behalf Of Fred Stevens
    Sent: Tuesday, December 13, 2011 1:44 PM
    To: NavList@fer3.com
    Subject: [NavList] Position discepancy


    I have a known location... well, "known" as far as Google
    Earth goes. I am assuming that it is a correct position
    since it is verified by GPS. When I go to either the NA or
    online almanacs, like USNO Almanac or Henning Umland's to
    verify the coordinates using Jupiter and Polaris, there is
    always a significant discrepancy between them and those from
    GPS/GoogleEarth, a few nautical miles at the very least.
    Enough to be worrisome if at sea.

    Any idea why so much difference?

    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