RE: 12044A / 38744: altitude increasing?

From: Ted Molczan (
Date: Sat Aug 11 2012 - 15:53:56 UTC

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    Bob Christy wrote:
    > In the light of SpaceTrack's switching around of IDs and increasing
    > number of element sets published, I've revisited my reasoning as to
    > which ID is which launch component. I agree with Ted but by have
    > approached it from a different angle.
    > I still think it is the APT that is venting fuel or gas:
    The following are preliminary estimates, with little error checking.
    Assuming the Breeze-M core carried its maximum of 5200 kg of fuel, then all of it should remain. Add to that its
    approximate dry mass of 1420 kg, for a total of 6620 kg. I estimate that its mean cross-sectional area is about 5.31
    m^2. A/m would be ~0.00080 m^2/kg.
    I estimate that at shut-down the APT still contained about 6538 kg of fuel. In an NSF forum, its dry mass was stated to
    be 950 kg. Total mass would be 7488 kg. I estimate that its mean cross-sectional area is about 8.1 m^2. A/m would be
    ~0.00108 m^2/kg.
    If objects 12044C and 12044D are the core and the APT, then the above A/m values suggest that their rates of decay
    should be roughly the same. In fact, the C object has exhibited negligible decay for the past couple of days, and D has
    exhibited a fairly high rate of decay since it reached orbit.
    Since C and D should be several times as massive as the payloads (12044A and B) and probably have no greater
    cross-sectional area than A and B, I would expect both to have significantly lower rates of decay than A and B, but that
    is true only of C. D has been decaying at 3 to 4 times the rate of A and B. Could that be because D is the APT, which
    somehow has vented most of its fuel?
    As for C, there is room for doubt that its recent negligible rate of decay and fluctuations in mean motion are due to
    fuel leakage. It may turn out to be due to unusually slow convergence to a realistic rate of decay. The situation will
    become clearer as additional TLEs are released.
    Before hitting send, I checked Space Track again, and I found that they have now attached the following names:
    12044A TELKOM 3
    12044B EXPRESS MD2
    12044C BREEZE-M R/B
    12044D BREEZE-M DEB
    Ted Molczan
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