Been out of the game for sometime. Increase in UNID passes???

From: Terminally Tired (
Date: Wed Jan 28 2009 - 08:23:48 UTC

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    Greetings ppl,
    Its been forever since I last posted here, and maybe 5 years since I have 
    had time to undertake visual satellite observation as a hobby.
    Having found myself with some spare time of late, and the IYoA 2009 
    rekindling my passion for everything heavenly, I have been out over the past 
    few nights with a laptop, a trusty pair of binoculars and the latest 
    visual.tle from the celestrak website.
    One thing that struck me as different to what I remember, is the higher 
    number of bright unexpected and unidentified passes that I have been 
    observing.  Almost all of these passes have been direct N-S or S-N and 
    around mag 3.8 or brighter.  Curious as I am I thought I'd grab a copy of 
    the old alldat.tle and have a bash at identifying any such passes I see in 
    the future.  Alas it seems that DoD policy changes have put paid to that 
    particular file.  Not to be deterred I signed up at and 
    grabbed their entire catalogue as a bulk download.
    Whilst on, I noticed that they have made available their own 
    version of a visual satellite file (visible_3l_200X_XX_XX_Xm.txt) which has 
    some 216 objects in it as opposed to the 154 in TS Kelso's visual.tle.  Can 
    anyone comment on the difference between these two files? (and/or)  Is 
    anyone aware of the selection criteria for each file?
    In my travels I came across the Fengyun 1C debris file at celestrak.  I also 
    read the analysis of the ASAT test and resultant debris swarm provided at 
    the site.  Having since checked the RCS values of the Fengyun 1C debris I 
    notice that some of the pieces appear quite large, with around 40 surpassing 
    a value of 1.0,  20 up over 2.0 and 10  having an RCS greater than 3.0. 
    This leads me to the questions:
    Is it likely that the perceived increase in UNID's is due to Fengyun 1C 
    Have many people successfully observed the larger pieces, and if so what 
    magnitude should I expect to see them at?
    Jason Gibson
    145.07E 38.03S  5M 
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