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
    Russian data
    From: Dave Walden
    Date: 2021 Jun 30, 13:11 -0700

    http://iaaras.ru/en/dept/ephemeris/online/

    russian data (and easy access to US and French as well)

    if you get as far as topocentric, you need to think like a russian astronomer.  I.e., coordinates are: 

    long

    rho sin phi

    rho cos phi

    where phi is latitude.

    recall WGS-84 constant:

    earth flattening=1/298.257223563 (or 1-1/f  =  0.996647189)

    then, if u  = atan( 0.996647189 tan phi)

    we have:

    rho cos phi = cos u

    rho sin phi = 0.996647189 sin u

       
    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