NOSS 3-2 post-manoeuvre elements

From: Ted Molczan (molczan@rogers.com)
Date: Wed Dec 31 2003 - 11:07:55 EST

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    Very timely observations over a 43 h period, by Tony Beresford, Russell Eberst,
    Paul Gabriel and Steve Newcomb have captured two manoeuvres by 03054A, to match
    the mean motion of 03054C, freezing (for now) their time separation at 11.3 s.
    
    The situation with 03054A's orbit was extremely confusing after Steve and Paul's
    obs on consecutive passes last night.
    
    Steve's points, added to Russell's pair of Dec 29, yielded the first accurate
    mean motion after the manoeuvre that preceded Russell's obs:
    
    Observation arc 2003 Dec 29.72 - 30.99 UTC:
    
    NOSS 3-2 (A)     0.0  0.0  0.0  4.9 v
    1 28095U 03054A   03364.96445584  .00000058  00000-0  10000-3 0    07
    2 28095  63.4304 230.9972 0124883 178.7269 181.4098 13.40517420    02
    
    WRMS residuals = 0.022 deg
    
    Paul's single 03054A point one rev later, was about 0.5 s early relative the
    above orbit? Had it manoeuvred in the interim? Had Paul reduced the wrong star
    pair? I actually found a an alternative star pair, that was in excellent
    agreement with the above orbit.
    
    Meanwhile, Steve and Paul's obs were in agreement on 03054C, which still had not
    manoeuvred:
    
    Observation arc 2003 Dec 17.78 - 31.07 UTC:
    
    NOSS 3-2 (C)     0.0  0.0  0.0  4.9 v
    1 28097U 03054C   03365.03918108  .00000028  00000-0  49374-4 0    09
    2 28097  63.4365 230.9936 0127120 180.2910 179.8061 13.40601359    05
    
    WRMS residuals = 0.019 deg
    
    Before posting any orbits, I decided to await either a credible referee
    observation of 03054A, or Paul's confirmation of his reference stars.
    
    Tony's observations, more than 11 hours later, make it clear that 03054A had
    manoeuvred again, and that it likely did occur in the one rev interim between
    Steve and Paul's obs last night.
    
    Here is the preliminary orbit, using Paul's and Tony's observations:
    
    Observation arc 2003 Dec 31.07 - 31.53 UTC:
    
    NOSS 3-2 (A)     0.0  0.0  0.0  4.9 v
    1 28095U 03054A   03365.48661053  .00000058  00000-0  10000-3 0    06
    2 28095  63.4304 229.6815 0124883 178.7250 181.4117 13.40602325    04
    
    The new mean motion very nearly matches that of 03054C, which Tony's obs
    confirms still had not manoeuvred:
    
    WRMS residuals = 0.021 deg
    
    Observation arc 2003 Dec 17.78 - 31.53 UTC:
    
    NOSS 3-2 (C)     0.0  0.0  0.0  4.9 v
    1 28097U 03054C   03365.48674127  .00000030  00000-0  52746-4 0    08
    2 28097  63.4373 229.8536 0127165 180.3311 179.7650 13.40601466    04
    
    WRMS residuals = 0.019 deg
    
    So my prediction that 03054C would manoeuvre to stabilize their separation was
    incorrect. It was 03054A that made the necessary manoeuvres.
    
    I will try to determine the time and location of the recent manoeuvres, and will
    report my findings.
    
    Ted Molczan
    
    
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