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: Venus ex-mer backsight dipshort
    From: Greg Rudzinski
    Date: 2011 Jan 16, 11:49 -0800


    Good going on capturing the rare Venus ex-meridian dip short backsight.

    Dip short from 106 feet seems to be very sensitive to horizon distance estimation.
    -60.4' at 1.0 NM
    -48.5' at 1.25 NM
    Dropping the height of eye down would help a lot here.

    For this exercise a LOP is determined by a smartphone Palm CN program:
    Azimuth 190.1�
    Intercept 6.5' away

    This gives me something to compare the ex-meridian to.

    As Requested (Venus 8m 27s after M.P.)

    1. (a) = 1.9635(Cos7�16.3')(Cos18�30.0')/Sin(11�13.7') = 9.48

    2. Ex.corr. = 9.48(8.45)(8.45)/60 = 11.3'

    3. Dip short correction is -48.5' for a 1.25NM horizon from an H.E. of 106ft. *

    4. Latitude 7� 10.1' S (6.2 NM away)

    * an online calculator was used for the dip short calculation

    Greg Rudzinski
    NavList message boards and member settings: www.fer3.com/NavList
    Members may optionally receive posts by email.
    To cancel email delivery, send a message to NoMail[at]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