ISS rendezvous orbit for Soyuz

From: Thomas Fly (
Date: Mon Apr 19 2004 - 14:02:40 EDT

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    Kevin got a reply back from MCC saying they don't release TLEs for Soyuz (though
    OIG may).
    Assuming OIG doesn't- at least not in a timely manner- this seems like an
    opportunity for the SeeSat folks.
    Since changing a plane of orbit is expensive (except for the "free" precession
    of orbital plane provided by the earth's equatorial bulge), it would seem that
    Soyuz must launch into approximately the same orbital plane as the ISS... at the
    time of rendezvous, the orbital planes must coincide (if Soyuz is initially in
    an elliptical orbit, with a shorter orbital period than the ISS, then its
    orbital plane should precess a bit faster than that of the ISS).
    It seems to me that initially you'd want to go into an elliptical orbit, having
    an apogee about the same as the ISS.  The orbital period would be such that,
    between launch & rendezvous, Soyuz would catch up with the ISS- obviously, some
    substantial rocket firing must be necessary to get Soyuz into the same orbit as
    the ISS, not long before rendezvous (i.e., basically circularizing its orbit).
    The MCC has released TLEs for shuttle flights to the ISS, which should shed some
    light on how rendezvous is accomplished- one would think that Soyuz & the
    shuttles would do it basically in the same way.  Does anybody have the TLE
    ephemeris for a past shuttle to ISS mission?
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