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: Precision of lunars
    From: Frank Reed
    Date: 2007 Apr 25, 23:28 -0400

    Alex, you wrote:
    "Can you cite or post ANY data or statistics"
    uh... sure!
    With a good, well-adjusted sextant, I get a standard deviation for Moon-Sun
    lunars, and of 0.2 minutes of arc on individual sites. On sets of four,
    averaged, I get an s.d. of 0.1 minutes of arc. For Moon+other object
    brighter than magnitude 0.5, I get similar results. With fainter stars, the
    results are progressively worse (bear in mind that something like 80-90% of
    the historical lunars I've seen in logbooks are Sun-Moon lunars). These
    results haven't changed in years for me, but it all depends on the sextant.
    It has to be an instrument that has been well-adjusted, tested for arc
    error, made of metal (no plastic sextants for lunars!), and carrying a
    telescope with a magnification of 7x or better. Now, if you want to see data
    for individual sights, I posted many series during the 3.4 years I've been
    on the list. You can search the archive if you want: www.fer3.com/arc
    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