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: Children's land-locked "Sextant"
    From: Bill Noyce
    Date: 2007 Nov 27, 10:46 -0500

    This may not give the level of precision you're looking for, but it's
    simple and easy for kids to understand:  Make a quadrant out of
    cardboard.  Print the protractor with a laser printer, either directly
    onto light cardboard, or onto paper that you glue to heavier
    cardboard.  Make sure the zero is parallel to one edge of the
    cardboard.  Cut around the arc so you have a quarter-circle, or a
    half-circle, or something in between.  Poke a tiny hole exactly at the
    vertex, and insert a thread.  Tape it in place on the back, and tie a
    weight (I used washers or nuts) so the thread hangs taut just below
    the arc.  Tape a drinking straw along the edge of the cardboard for a
    sight, so it is supported by the edge like this:  O==  To sight stars,
    you look through the straw with one eye, and around it with the other,
    and place the star at the center of the circle.  Rock the quadrant
    until the stationary thread just grazes the cardboard, pinch it in
    place, then read it.  You should be able to read to 15' or better with
    a reasonable-sized scale, though your sights will likely have more
    scatter than that.  For the sun, don't look through the straw --
    instead, watch the quadrant's shadow, and point the straw at the sun
    until its shadow becomes an "O".  Again take care that the quadrant is
    in the vertical plane, and pinch the thread.  (This measures to the
    center of the sun, not to either limb.) You should check each quadrant
    for index error -- assuming your printer is properly adjusted, and the
    thread pivots in the center of the arc, other errors should be
    negligible.  Good luck!
        -- Bill
    
    On 11/27/07, Isonomia  wrote:
    >
    > I'm camping next summer with a load of 11year old kids and wanted to
    > do some celestrial navigation and plot a position to within
    > 10-20miles.
    
    --~--~---------~--~----~------------~-------~--~----~
    To post to this group, send email to NavList@fer3.com
    To unsubscribe, send email to NavList-unsubscribe@fer3.com
    -~----------~----~----~----~------~----~------~--~---
    
    

       
    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