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
    Name or NavList Code:
    Email:
       
    Reply
    Re: Believe it or not
    From: Alexandre Eremenko
    Date: 2007 Jan 26, 13:43 -0800

    Here is more of the same.
    January 26, GMT 20:20, sunny weather strong wind T=44(F) P=29.1in
    Sun-Moon at approx 101 degrees.
    
    Pocket Troughton ans Simms, IC=0.
    GMT:                20:58:00  21:00:40  21:02:30  21:04:20  21:07:05
    21:08:10
    sextant reading: 101d40'   101d43'    101d41'   101d43'    101d44'
    101d44'
    It was immediately clear (after the third observation, and CERTAINLY
    before the reduction)
    that the second observation was a blunder and I decided to discard it.
    Here is the sequence of errors, including the blunder (reduced with
    Frank's calculator):
    0.0' , 1.8' , -0.9',  0.3, 0.2, -0.3.
    If one discards the blunder, the average error is -0.14, sigma=0.5, and
    if one does not discard, then the average error is 0.18 with sigma=0.9.
    Not bad for a 2 inch sextant:-)
    
    Here is SNO-T, for comparison IC=-0.5, I list the errors of 11
    observations:
    -0.2, 0.3, 0.1, 0.4, 0.4, -0.2, -0.2, 0.3, -0.3, 0.1, -0.1 .
    Average error 0.05, sigma=0.3.
    The first 5 observations were made with filter number 1, and the last 6
    with
    filter number 2. That filter number two gives a bit smaller reading
    than filter
    number 1 was known to me. It is hard to tell which of them is "right".
    If one computes the averages separately one gets 0.2 for the first
    filter
    and -0.1 for the second one. In the IC determination both filters were
    used,
    and average was taken.
    
    Alex.
    
    
    --~--~---------~--~----~------------~-------~--~----~
    To post to this group, send email to NavList@fer3.com
    To , send email to NavList-@fer3.com
    -~----------~----~----~----~------~----~------~--~---
    
    

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Get a NavList ID Code

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    A NavList ID Code guarantees your identity in NavList posts and allows faster posting of messages.

    Retrieve a NavList ID Code

    Enter the email address associated with your NavList messages. Your NavList code will be emailed to you immediately.
    Email:

    Email Settings

    NavList ID 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