NROL-1 observations

From: Ted Molczan (
Date: Tue Aug 31 2004 - 23:17:51 EDT

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    Well, I certainly made of mess of the planning for tracking of this launch!
    A few days ago, I ran some predictions for my location and one or two others in
    North America, and erroneously concluded that the early part of the Centaur's
    climb to apogee would occur in daylight, or very bright twilight.
    So, instead of planning to track the NROL-1 Centaur, I set up my binoculars for
    routine tracking of 03790B. I had found my intercept stars, and had 10 minutes
    to kill until the satellite arrived.
    All of a sudden, in the nearly cloudless sky, I spotted an approximately 0.5 deg
    diameter glowing cloud, slowly rising in the west. 
    For a moment, I thought it might have been a real cloud, but it was too bright,
    so I aimed my 11x80's at it, and saw that it had considerable structure, and
    seemed to emanate from a jet-like structure.
    Shortly afterward, I saw a bright flash from an object near the end of the jet
    opposite the cloud, by which point I knew that had to be from tonight's launch
    of NROL-1, most likely the Centaur's propellant dump.
    I managed to obtain the following positions:
    72000 04 034B   2701 G 20040901005917130 17 25 1540326+161016 68 R
    72000 04 034B   2701 G 20040901010243750 17 25 1604058+251534 68 R
    72000 04 034B   2701 G 20040901010330500 17 25 1609463+271046 68 R
    I had time to sketch the reference stars of the first and third point, so I am
    absolutely confident of those positions. The second point was of an appulse of a
    star, which I did not stop and sketch. 
    These positions are necessarily rough, because the Centaur was visible only in
    brief flashes, roughly 5 to 10 s apart. I knew its approx location relative the
    cloud, and used that as the basis to judge its position relative the reference
    Each point was progressively early relative my pre-launch estimated orbit (shown
    below); therefore, I now believe that the apogee of the orbit is much lower.
    1 72000U          04245.01776620  .00000000  00000-0  00000-0 0    06
    2 72000  58.4281 233.3614 7445000 290.0637   0.0000  2.00600000    06
    In all the excitement, I broke an arm off of my glasses, which severely hampered
    my ability to make sketches. 
    I was observing from a balcony, and considered making a dash to the roof to
    continue tracking, but I decided the prudent thing would be to make certain of
    the data already in hand.
    I apologize for failing to provide advance notice of the opportunity to observe
    this event.
    Ted Molczan
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