Re: TDF 1 is flashing ??

From: paul (astro@pgog.net)
Date: Tue Sep 03 2002 - 11:01:52 EDT

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    Rob, Bjorn, Ed...
    other than Ed suspects the 20.8 sec flasher could be
    a different sat, Cosmos 2282 23168 94038A, this is encouraging
    news, although at the moment tropical cloudiness is 
    as unpredictable as seeing TDF 1 has been lately :)
    Let me summarize, then I may have a few questions that Rob
    or Bjorn are better able to analyze.
    Rob reports 20.8 sec flasher 03sep 0415 ut +5->inv that he
    timed for ~ 12 min.  Ed also timed a 20.8 sec flasher for
    105 min during the same timeframe, more or less.  I haven't
    seen PPAS reports from either Rob or Ed yet.  
    I'm not sure whether the flasher was TDF 1 or Cosmos 2282,
    but Ed is correct that they were together last night, at
    0415 ut angular separation of only 2.2 deg PA 285.  They
    remained in these relative positions during a 105 min frame
    from 0415 - 0600 ut and both would have been in my bino fov.
    I did not setup to look 03sep ut, due to clouds, which had
    cleared enough for me to trak LEO 24753.  To clarify for
    Ed, when looking for TDF 1 I have been using binos w/5.3 deg
    fov on locked mount (w/az/el positions adjusted as needed 
    ref TDF 1 slow az/el drift :)
    When I looked 02sep 0822 - 0842 ut (immediately post-immersion
    into sunlight per suggestion from Bjorn) no flashes seen AND
    Cosmos 2282 was outside my fov and in shadow.
    The UT times I recall looking the past few days, 0210 - 0235,
    0120 - 0140 (I had to leave), & 0822 - 0842.  
    Prior to Ed's comment of last night, 20.8 sec flasher for 105 min,
    I had understood that the real TDF 1 had a much shorter flash
    visibility frame, perhaps on the order of 15 mins, but my
    understanding re this could be a misunderstanding.
    but since I have not looked at the UT times that Rob saw flasher
    last night, it could have been flashing those nights for
    105 mins and still been outside the visibilty window that I 
    was looking -- and here is where further analysis of Rob and
    Bjorn would be helpful.  
    given Ed's message, which sat is more likely for last night's
    20.8 sec flasher, TDF 1 or cosmos 2282 ??
    if Rob saw flashes at 0415 ut, from CA, would I see them about
    the same time from S_Texas ??  (seems Ed did from Central Tex)
    is it "safe" to add ~ 12 min and start looking at 0427 04sep ut?
    (tropical clouds may preclude a view from here tonight)
    caveat: cosmos 2282 does remain close ~ 2.7 deg PA 84 from TDF 1
    and if I was correctly centered on TDF 1 location cosmos 2282
    would be just outside my bino fov (5.3/2=2.6), although I could
    center midway between the 2 and see them both.
    In light of Ed's message and the cosmos 2282 "complication"
    feedback would be helpful
    -- the expected total total visibility period of TDF 1
    -- what to expect 04sep ut re this total vis and start time
    -- previous PPAS reports of cosmos 2282 (if I'm reading the data
    correctly, I find no PPAS reports for cosmos 2282 94- 38A which might
    lend support that the 20.8 sec flasher IS TDF 1, flashing in
    a window that I have not looked the past few days).
    now I'm psyched which usually leads to overcast skies.
    as an aside to Ed (& fearing the "wrath" of Mike and Ted)
    findsat and IDsat might be giving you data somewhat 
    difficult to interpret with geos and near_geos based on
    my recent experience in that regard, but someone might
    clarify that for us??)(Guide8 & skymap give onscreen map
    data more easily understood re geos & near_geos IMO)
    
    
    At 21:55 9/2/2002 -0700, you wrote:
    >Hi Paul, Bjorn and List,
    >
    >I haven't contributed much lately, partly due to time spent
    >on meteorite work and SOHO comet hunting, but primarily due
    >to perpetually poor skies this summer.  Well, we finally
    >got a nice high pressure ridge, so seeing is excellent
    >tonite.  I've been following the recent threads on attempting
    >to reacquire TDF-1 (#19621) and determine its current flash
    >period (and flash window timing), so that was first on my
    >agenda this evening.
    >
    >I acquired it within 10 seconds of putting my 8x56 binocs
    >to M11 -- it (the satellite that is) was flashing nicely to
    >around 5th magnitude as of 21:15 PDT (9/3 4:15 UTC).  I
    >started the stopwatch at 4:17:15.2 on a flash and timed
    >33 flash periods in 688.63 seconds for a flash period of
    >20.868 +/- 0.002 seconds.  Unfortunately my PPAS template
    >is on my work computer, so a properly formatted report
    >will have to wait 'til tomorrow.  Just wanted to get
    >something out quick in case any west coast satellite
    >trackers wanted to try to acquire it.
    >
    >While watching TDF-1 for those 15 minutes or so, I watched
    >a dim LEO pair ascending from the south not far from TDF-1,
    >their paths criss-crossing each other, only slightly out
    >of phase.  This made identification easy:  GEO-IK (#23411,
    >94078A) and NOAA 2 (#06235, 72082A).  They both appeared
    >around magnitude +6.5.  Back to satellite watching!  --Rob
    >
    >P.S. Observations from my usual COSPAR location in
    >Newport Coast, CA  33.6028N, 117.8263W, ~200m AMSL (WGS-84) 
    
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