Latest USA 129 elements; manoeuvre alert continues.

From: Ted Molczan (
Date: Tue Apr 18 2000 - 10:46:45 PDT

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    Pierre Neirinck produced these elements, using observations by himself, Russell
    Eberst, Ted Molczan, Jim Nix, Alberto Rango and Rainer Kracht, from 14 - 18
    April UTC:
    USA 129         15.0  3.0  0.0  5.1 v
    1 24680U 96072A   00109.15311330  .00045568  00000-0  58782-3 0  4425
    2 24680  97.8919 173.0971 0477233 173.5285 187.1105 14.84312587    06
    I have been trying to refine the theory as to the rules governing the date/time
    of both Keyhole’s apogee-raising manoeuvres.
    In brief, I find that in addition to mean motion of approximately 14.84 rev/d,
    one of the two Keyhole’s perigee will be near either its ascending or
    descending node. History also shows that it could be the one in the western
    plane (USA 129) or the eastern plane orbit (USA 116). If the former, then the
    burn we have been expecting should have occurred on or about 16 April; if the
    latter, then 26 April.
    The 10 day difference is the additional time required for the eastern-plane
    orbit’s perigee to precess to its next node crossing.
    I suspect that the tolerance is perhaps one day. If so, then it appears that
    the currently anticipated manoeuvres may not have been planned for USA 129's
    perigee-at-node, in which case, the maneouvre should occur at USA 116's
    perigee-at-node, on 26 April, +/- 1 day or so. Time will tell.
    Since we don't know the exact tolerances, the manoeuvre should be assumed to be
    imminent, so the alert continues.
    A detailed explanation and rationale is found my post earlier today:
    Ted Molczan
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