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: Position fix by satellite
    From: Greg Rudzinski
    Date: 2014 Jun 25, 08:14 -0700

    Tom,

    What is given for the ISS on various web sights is the geographic position and altitude for any UT time. I got an ISS GP Lat 51.659° N ; Lon 4.069° W at an altitude of 225.78 nautical miles for 6/23/2014 16:15:29 UT. Then the Sun's Hc altitude and azimuth can be worked up using the GP as the assumed position ( Hc 37° 4.38' Az 261.2°). This should be enough information to get a position with a known Earth radius. The position error will be +/- 16' semi diameter of the Sun. There is another less accurate way to get a rough position and that is to measure the width of ISS in pixels ( 11px ) vs. known length ( 109 meters ) and then use the Sun as a yard stick ( 547px ) with a solar diameter of 31.47167' for the day of the image. This will give an approximate line of sight distance from the photographer to the ISS setting up a long distance piloting problem.

    I have a hunch Frank has an easier way to do this though.

    Greg Rudzinski

    http://fer3.com/arc/m2.aspx/Position-fix-satellite-TomSult-jun-2014-g28110

       
    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