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: Artificial horizon question
    From: Jackie Ferrari
    Date: 2009 Apr 20, 21:30 +0100

    Hi Gary,
    Como is beautiful. I visited Volta's museum there. It has various types of
    cell that he invented. I took my sights in a little village called San
    Vincenzo near Borgotaro which is a few hours to the south by train.
    
    Jackie
    
    
    
    ----- Original Message -----
    From: 
    To: "NavList" 
    Sent: Monday, April 20, 2009 10:51 AM
    Subject: [NavList 7996] Re: Artificial horizon question
    
    
    
    Hi Jackie, I'm in Como Italy right now,
    gl
    
    On Apr 20, 9:12 am, "Jackie Ferrari"  wrote:
    > I've got good results for the moon and sun in a bucket of water on calm
    > days
    > . I once tried a star and managed its reflection ok using the method Gary
    > mentions. This was in Italy up in the mountains so no light pollution but
    > I
    > do recall the reflection was still very faint and the results not too
    > good.
    >
    > Jackie.
    >
    > ----- Original Message -----
    > From: "Gary LaPook" 
    > To: 
    > Sent: Monday, April 20, 2009 2:44 AM
    > Subject: [NavList 7993] Re: Artificial horizon question
    >
    > > Mercury has traditionally been used for an artificial horizon (see Lewis
    > > & Clark) and it is easy to shoot stars using Mercury. It is rather hard
    > > to come by these days and is not cheap and some worry about its safety
    > > (I'm not one of them if used with care.)
    >
    > > The second part of your question, compute in advance the approximate
    > > altitude of the star, double it and set your sextant to this value and
    > > then look for the star in the reflecting pool. The navigational stars
    > > are well separated and are bright so there should be no trouble in
    > > getting the right star.
    >
    > > gl
    >
    > > P H wrote:
    > >> Dear NavList Members,
    >
    > >> Since the nearest ocean is hundreds of miles away from where I live, I
    > >> must use an artificial horizon in order to work with my sextant. A
    > >> pan filled with water works fine enough for me for observations of the
    > >> moon at night and the sun. Now these days both the sun and the moon
    > >> are simultaneously visible during the day, which would allow for a fix
    > >> on one's position - if the altitudes of both bodies can be measured.
    > >> As you probably can guess, with all the glare I was unable to observe
    > >> the reflection of the moon... so here is my question: are there any
    > >> tricks that would allow one to construct a usable artificial horizon
    > >> for the daytime observation of the moon? And to take it one notch
    > >> further, how about an artificial horizon for the stars and planets (at
    > >> night, of course)? Are there any systematic methods to ensure that
    > >> the star reflected on the surface is indeed the one I intend to
    > >> observe?
    >
    > >> Many thanks.
    >
    > >> Peter Hakel
    >
    >
    
    
    
    --~--~---------~--~----~------------~-------~--~----~
    Navigation List archive: www.fer3.com/arc
    To post, email NavList@fer3.com
    To unsubscribe, email 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