Re: nasa says iss orbit boost for today is 5 mnutes long

From: Don (dtownhome@earthlink.net)
Date: Thu May 12 2005 - 03:41:06 EDT

  • Next message: Peter Wakelin: "SATOBS 2005 May 11/12"

    >Received:    5/11/05 5:10 PM
    >From:        satcom, john@satcom.freeserve.co.uk
    >To:          SeeSat-L (List addy), SeeSat-L@satobs.org
    >
    >Any ideas on how this will affect "arrival " time .....if  tles are not 
    >updated in time ?
    >I have a pass due here at  2118 gmt and am guessing it will be about
    >2 - 3 minutes late....does that sound about right  :O)
    >
    >John
    
    Hi John and everyone;
    
    I'm an amateurs amateur using an old Mac but ....
    
    I ran a little 'guess' starting with an older set of TLE's (about 10
    days old) and it looked to me like a little over a minute difference
    in arrival time between those two.  I'm not quite sure how you all
    get that there is only 1 second difference?
    
    According to my pass prediction software...
    
    the old TLE indicates ISS coming over the horizon at 22:26:46 local time
    The NEW TLE indicates ISS coming over the horizon at 22:27:48 local time
    
    Thing is... I'm not so sure how accurate the relationship is between
    the predicted TLE's, the 'old' ones, and how accurate the software is
    that I'm using in the first place... but then again, I'm a noobie at
    this stuff.
    
    So, am I making a mistake somewhere... using software that isn't
    maintaining accuracy, or comparing with a TLE that is way too old?
    Assuming I am the one making the mistake, perhaps the best question
    might be 'Might anyone have a clue what I am doing wrong?'
    
    Don
    
    -------------------------------------------------------------------------
    Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive:  
    http://www.satobs.org/seesat/seesatindex.html
    



    This archive was generated by hypermail 2b29 : Thu May 12 2005 - 03:59:37 EDT