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: GNSS is not immortal
    From: Frank Reed
    Date: 2018 Sep 24, 20:15 -0700

    Hi Steve! Welcome aboard.

    When I saw your message as originally posted, I thought "wow! that's a crazy long subject!" Then I read the long message and realized, "aha! this is three messages". So I split it up manually, and it all worked out fine.

    In this message, you wrote:
    "chain-reaction collisions of satellites in geosynchronous orbit rendering the entire orbit unusuable."

    This is not something that we have to worry about. Only LEO (Low Earth Orbit) is threatened by such a runaway scenario. And in any case, the GNSS constellations don't live in geosynchronous orbit! They are in MEO. There's a nice article with a good schematic drawing on Wikipedia: https://en.wikipedia.org/wiki/Medium_Earth_orbit. Of course that chain-reaction scenario is only one of the potential threats, but it's nice to know you can cross at least that one off, right?

    Frank Reed

    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