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: Arificial Horizons and Tea
    From: Doug Royer
    Date: 2003 Jul 10, 10:46 -0700
    I got tired of careing for and useing liquid horizons.I bought a piece of black glass 6x6 in square for $8.50.Had it polished on one side for $13.00 and it looks like a piece of obsidian.It is very reflective.Got 2 small liquid levels for $2.50 each.A piece of 6061 aluminum 7x7 in. square, 0.064 in. thick.Drilled and tapped for 6-32 machine bolts in each corner for leveling.Used RTV 3145 adhesive to bond the glass(polished side up) and levels to the aluminum plate.The levels are used in conjuction with the 4 corner bolts to level the surface of the glass.I have been useing it for 6 weeks now and can tell you that I have no problem seeing star images to take alt. measurements.Images of the Sun and Moon are astonishingly clear and the point of light of a star is crisp.There is no ripple on the glass surface to distort the relected images and the bothersome problems of wind and fluid have been eliminated.It is light in wieght yet robust and small in size.Throw it and a plastic sextant into the backpack and off you go not careing about carrying fluids other than to drink.Something to think about in a desert environment.
    All that said,I live in a very arid part of the south west that has very little humidity and atmospheric haze and at night very little man made light that washes out or interfers with the light of stars.The wind can howl out here and was the biggest problem in useing a fluid horizon.This cost me about as much as a new Davis plastic horizon.   
    -----Original Message-----
    From: Wolfgang Bosswick [mailto:wolfgang.bosswick@SOWI.UNI-BAMBERG.DE]
    Sent: Thursday, July 10, 2003 00:10
    Subject: Re: Arificial Horizons and Tea

    I guess, tea works fine for several good reasons: It is usually available without problems, you can drink it after the shots (while unboiled pure water might be risky), and finally, tea contains aromatic oils - they often leave brown traces on a white cup. These oils likely form a one mol thin film on the water, calming its surface. With pure water, the lightest air breeze causes a scattered sight, and you have to wait for seconds until the waves disappear.

    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