Re: USA 144 elements; photometric timings needed

From: Kurt Jonckheere (kjon@yucom.be)
Date: Sun Jan 19 2003 - 15:06:35 EST

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    hello Ted,
    
    I just noticed that the clouds were suddenly gone here, and though
    "let's see if this object is visible this evening".  Running predictions I
    noticed that it was visible at that moment (so I was more or less too
    late...) and hurried outside.
    
    As Ted didn't mention any brightness here, I was surprised to see
    an object with magnitude around +6 in my field.
    I could follow it from around 19h45m UT till it entered shadow
    around 19h47m47s.  During this two and a half minute I did not
    notice any obvious magnitude changes, certainly no deep minimum
    was seen.
    
    I will try to make a longer obs one of the next days if wheather permits.
    
    Kurt Jonckheere
    
    From: Ted Molczan <molczan@rogers.com>
    Subject: USA 144 elements; photometric timings needed
    
    
    > Arc 2002 Dec 27 - 2003 Jan 17 UTC:
    >
    > USA 144          0.0  0.0  0.0  3.6 v
    > 1 25744U 99028A   03017.82938300 -.00000054  00000-0 -82890-2 0    07
    > 2 25744  63.4491 297.9205 0239216 293.8148  63.7769  9.69791794    02
    >
    > WRMS error = 0.008 deg
    >
    > SRP (Solar Radiation Pressure) will continue to raise the altitude of the
    orbit until 2003 Feb 03 UTC.
    >
    > From Feb 03 through Mar 15, the orbit will be in constant sunlight,
    resulting in near zero SRP effect on altitude.
    >
    > Accurate timings of the object's photometric may be helpful in settling
    the question of this object's identity. As I reported last
    > August, the magnitude of the SRP effects raise serious doubts as to the
    identity and nature of this object:
    >
    > http://satobs.org/seesat/Aug-2002/0045.html
    >
    > The object correlates strongly with the 99028A launch; however, based on
    its apparent size and the SRP effects, its mass appears to
    > be no more than 10 percent of the expected mass of the payload. It could
    be debris or even a decoy.
    >
    > Here are the most recent photometric timings:
    >
    >        Observer                    Photometric Period - seconds
    > ------------------------------   --------------------------------
    > 2002 Aug 10 Pierre Neirinck      119 +/- 6
    > 2002 Aug 22 Ted Molczan          116.3
    > 2002 Aug 31 Ted Molczan          113.8
    >
    > Earlier timings are listed at the above URL.
    >
    > The object's slow rotation and deep minima make accurate timing a
    challenge. At times I thought I saw small, very brief secular
    > flashes that could provide a reference for timings.
    >
    > Ted Molczan
    >
    
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