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: Sun sights during an eclipse: "bad limb" calculation
    From: Antoine Couëtte
    Date: 2023 Oct 10, 14:52 -0700

    Extra checks from previous submission :

    From N28°00.0' - W090°00.0'  on Oct 14, 2023  (TT-UT = +69.7s)

    (1) - Check between Lunar Software and Heights Simulation Software

    All values refracted, and augmented as regards SD's 

    15h36m07.3s UT : ABS (Sun Center - Moon Center) Heights : 30.43140'  and  ABS (Sun Center - Moon Center) Azimuths * cos average height = 7.02818'

    Square root of the above : 31.23244'   Sun SD=16.02400' , Moon SD=15.19500'  Sun SD + Moon=31.21900' Difference: 31.23244'-31.21900 ' = 0.01'

    18h51m13.1 UT : ABS (Sun Center - Moon Center) Heights : 16.73580'  and  ABS (Sun Center - Moon Center) Azimuths * cos average height = 26.43003'

    Square root of the above : 31.28312'   Sun SD=16.02750' , Moon SD=15.23550'  Sun SD + Moon=31.26300 ' Difference: 31.28312'-31.26300' = 0.02'

    Hence the Lunar Software and the Simulation Software - totally different Software -  give results fully consistent with one another.

    (2) - Check with Frank E. Reed's On Line Lunar Computer

    From N28°00.0' - W090°00.0' at 15h36m07.3s UT with Lunar distance = 0°00.0' : Error in Lunar 0.08'

    From N28°00.0' - W090°00.0' at 18h51m13.1s UT with Lunar Distance =0°00.0' : Error in Lunar 0.18'

    This independent check indicates that the UT times determined through (1) are realistic and are not far from actual values (certainly within 6" and probably within 4" as most often observed).

    Kermit

       
    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