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
    Name or NavList Code:
    Email:
       
    Reply
    Lecky's locations and WGS 84
    From: Tim Ingham
    Date: 2022 Jul 15, 20:52 -0700

      Can anyone clarify what changes are required to be applied to the originally quoted latitude and longitude of a point which was based on when “Greenwich Meridian” was the zero Meridian and now, when Lat and Long are quoted in terms of WGS 84 and the zero meridian is about 5.3” east of the “Greenwich Meridian”.

    The query is prompted by a check on some data quoted in Lecky’s Wrinkles in navigation (1884)  which claimed 2 locations, St. Paul’s rocks and Cape Agulhas Lighthouse to be “Both of these are very accurately observed positions”. The other locations are taken from his List of Time Signals. 

    Also, I appreciate the need for caution when quoting “Mr Wikipedia”, but what information is there on the accuracy of Google Earth’s Lat and Long positions?

    File:
    Lecky_location_differences_a.xlsx
       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Get a NavList ID Code

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    A NavList ID Code guarantees your identity in NavList posts and allows faster posting of messages.

    Retrieve a NavList ID Code

    Enter the email address associated with your NavList messages. Your NavList code will be emailed to you immediately.
    Email:

    Email Settings

    NavList ID 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