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: Working Analemma
    From: Bill Noyce
    Date: 2006 Nov 12, 10:49 -0500

    On 11/11/06, James R. Van Zandt  wrote:
    > Lu Abel  wrote:
    > >   The UPS "analemma" is a stainless steel path about 2 inches wide,
    > >   inscribed at about 10 day intervals.  It was constructed based on a
    > >   set of plans provided by a professor who had to very carefully
    > >   calculate the distortions induced by the location of the mirror.
    > >   Although it hasn't been in service for a full year, I hear it's
    > >   doing fine so far....
    > I assume that it works at solar noon each day.  I wouldn't be
    > surprised if they need to post a conversion table between solar time
    > and what the clocks are set to.
    No, that's what the "width" of the figure-8 analemma is for.  It corrects for
    the equation of time.  Of course, daylight-savings time is a different problem.
    > Which reminds me - do you remember the analemma that Tom Hanks'
    > character drew in the cave in Castaway?  He used it as a calendar.
    > Except that he could only have created or used it if he had accurate
    > time.
    Yeah, what a shame.  It was such a beautiful idea.
        -- Bill
    To post to this group, send email to NavList@fer3.com
    To unsubscribe, send email to NavList-unsubscribe@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