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
    or...
       
    Reply
    Re: The Three-body Problem
    From: Dave Walden
    Date: 2021 Oct 27, 04:37 -0700

    The JPL DE430 ephemeris used for the Nautical Almanac doesn't approximate a 3 body problem.  It includes the interactions of over 350 bodies.  All the planets plus largests asteroids.  It calculates interactions based on physics and then time steps.  New versions of the DE series include all new data from ground based position obervations, spacecraft tracking data, and laser and radar ranging data.  It reflects planet shape effects, relativistic effects and others.  See for example:

    https://ipnpr.jpl.nasa.gov/progress_report/42-196/196C.pdf

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    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:

    Email Settings

    Posting 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