UNID or not? 11 May 2009

From: Marco Langbroek (marco.langbroek@wanadoo.nl)
Date: Wed May 13 2009 - 09:51:55 UTC

  • Next message: Greg Roberts: "Optical 10 May 2009-last"

    Hi all,
    
    On the evening of May 11-12 I obtained a photograph of three objects closely 
    together: ISS, Meteor 1-4r (70-037B) and a third object with identification 
    problems.
    
    It is a faint object with a trajectory paralell but somewhat ahead and south of ISS.
    
    The trail was captured only partly as one end exits the image border. The one 
    visible endpoint gives either (depending on unknown direction of travel - it was 
    not seen visually):
    
    91999 09 999A   4353 G 20090511215412300 17 75 1503070+193890 56 S+060 10
    
    or:
    
    91999 09 999A   4353 G 20090511215422350 17 75 1503161+193890 56 S+060 10
    
    The first line is valid when direction of travel is similar to the ISS (i.e, 
    moving parrallel and ahead of it).
    
    I have one potential candidate but with a bad fit: Kosmos 546 (73-005A). 
    Direction of travel is okay, but it yields a large cross-track error (-0.14 
    degree) and large delta T -0.57s.
    
    This while, by comparison, the Meteor 1-4r in the same image yields x-track 
    0.03, delta T -0.16s and ISS x-track -0.01 delta T -0.15s (my thumb seems to 
    have been slightly fast on this one, which wasn't an image intended for 
    positional measurement anyway). So the fit of Kosmos 546 is way worse in both 
    x-track and delta T than for the other two objects, from the same image and 
    astrometric reference frame.
    
    Image can be seen here:
    http://i19.photobucket.com/albums/b176/marcoaliaslama/satellites/110509ISS_UNID.jpg
    
    Thoughts and opinions are welcome.
    
    - Marco
    
    -------------------------------------------------------------------------
    Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive:  
    http://www.satobs.org/seesat/seesatindex.html
    



    This archive was generated by hypermail 2b29 : Wed May 13 2009 - 09:58:32 UTC