Re: Geostationary and Repositionable?

From: Allen Thomson (thomsona@flash.net)
Date: Tue Apr 25 2000 - 12:38:29 PDT

  • Next message: Ted Molczan: "USA 129 elements; manoeuvre alert."

    Routersaurus Rex asked,
    
    > Can a Geostationary sat be repositioned?
    > Not simple station keeping, but moved thousands of kilometers to another
    > position?
    
    Sure, easily, by doing a small thruster burn to change its period from exact
    geosynchronicity, letting it "drift" to the new location (which is what the
    operators actually call the operation) and then doing a reciprocal burn to
    restore the period to 1 rev/day.  IIRC, LES-9 was moved most of the way
    around the planet to cover Desert Storm in this way.
    
    > Seems to me a GS sat would make a good spy platform if it could be moved
    > about, of course the extreme altitude would cause difficulties.
    
    The US' GEO SIGINT platforms have been known to shift around a bit, and
    there's a developing story about a GEO satellite inspector that drifts
    around looking at/listening to other satellites.   Optical reconnaissance of
    the ground from GEO would need a pretty big aperture, though a Hubble-class
    mirror could get 10-meter SPOT-like pictures.
    
    > Oh, another thing, are there *any* satellites that in equitorial orbits
    that
    > circle the earth to the west?
    
    No, there are some that are seriously retrograde (the Israeli Ofeq
    satellites, for example), but none really close to 180 degree inclination
    that I know of.
    
    
    -----------------------------------------------------------------
    Unsubscribe from SeeSat-L by sending a message with 'unsubscribe'
    in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org
    http://www2.satellite.eu.org/seesat/seesatindex.html
    



    This archive was generated by hypermail 2b29 : Tue Apr 25 2000 - 12:40:22 PDT