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: A question for the geodisists
    From: Gary LaPook
    Date: 2013 Dec 19, 03:27 -0800
    That was interesting but still doesn't answer my question. I note that it shows an example of an island being shifted 1/2 NM but Howland was shifted one whole nautical mile.

    In 1936 officers from the Coast Guard cutter Itasca went ashore on Howland island and took sextant shots to determine the position of the island. The coordinates that they found were 0° 48' north, 176° 38' west and these were published in Bowditch (1938 ed.)  and are still published in H.O. 126. The newest chart shows the longitude to be 176° 37' west, one full nautical mile to the east. The chart states that this was due to shifting horizontal datums. But my question is really simple, what is the longitude of the center of the island as determined by celestial navigation, not by satellite? Were the Itasca's officers simply wrong and they should have also calculated the new value if they had been accurate? What would a celestial navigator determine the longitude of the island to be if he took the observations tomorrow?

    gl



    From: Andrés Ruiz <navigationalalgorithms@gmail.com>
    To: garylapook@pacbell.net
    Sent: Thursday, December 19, 2013 12:44 AM
    Subject: [NavList] Re: A question for the geodisists


    2013/12/18 Gary LaPook

    So what is the answer to my question?

    Gary, this may be the key
    http://msi.nga.mil/MSISiteContent/StaticFiles/Files/NautChrts_GPS_index.htm
    --
    Andrés Ruiz
    Navigational Algorithms
    http://sites.google.com/site/navigationalalgorithms/
    Attached File:

    (img/125838.using nautical charts with global positioning system.pdf: Open and save or View online)

    View and reply to this message: http://fer3.com/arc/m2.aspx?i=125838


       
    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