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: The flat earth notion
    From: Bill Noyce
    Date: 2003 Nov 5, 12:12 -0500

    > A loxodrome only reaches either pole after
    > _infinite_ time, gradually spiralling in towards the pole but never
    > quite getting there.
    
    Although a loxodrome spirals around the pole an infinite number of
    times, it has only a finite length.  That's one of the funny things
    about it.  To see this intuitively, imagine it has gotten close enough
    to the pole that the earth can be considered to be flat.  In this
    case, the loxodrome degenerates to a planar logarithmic spiral --
    a spiral that cuts each radius at the same angle.  The logarithmic
    spiral has the property that there is a constant factor f between
    the length of one 360-degree segment and the next.  Therefore, the
    total length of the inward spiral, starting from where the path is
    one mile long, is 1 + f + f^2 + f^3 + ..., which is finite as long
    as f<1.  (The familiar case where f=0.5 adds up to 2.)
    
    
    

       
    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