European Space Agency story of Tomás Maruska's ISS / Venus transit

From: Thomas Fly (
Date: Thu Jun 24 2004 - 14:11:15 EDT

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    It states, "Few of the images of this unusual astronomical event will have been
    as unique as those taken by Tomás."
    In fact, apparently none are; nor is there any guarantee that during the Venus
    transit of 2012, the orbit of the ISS will be favorably aligned, relative to the
    Earth's terminator, even to allow such a photo / video; so Tomás' photo may be
    IT, now and forever.
    Hopefully, of course, something grander will be in the skies during the transit
    of Venus in 2138, though it's not unlikely that anyone reading this will see
    Probably the most charming aspect of this story is that, after all of my
    efforts, and those of Arnold Barmettler / CalSKY, to precisely forecast the ISS
    / Venus transit path, Tomás was merely trying to get a video of the ISS passing
    across the Sun coincident with Venus, SOMEWHAT NEAR Venus!  When he saw that his
    Uncle's home was within the ISS / Sun transit path, that was where he went.
    So, Tomás' video, which gives an impression (quoting Ted Molczan) of:
    "A beautiful display of celestial mechanics, resulting from a considerable
    knowledge of what's under the hood." *
    in fact had as much to do with where his Uncle happened to buy a house!...
    * And, I might add, brilliant software engineering!
    "As with life in general, luck plays a big part in the pursuit of transits  ;-)"
    Currently, there also appears to be some confusion regarding the accuracy of the
    predictions, (and some ironies, as well!).
    As late as my final predictions of June 7, I'd been trumpeting the superiority
    of the MCC generated TLEs (at least, when they're not too old) that I use for my
    transit alerts, over the OIG TLEs that CalSKY presently uses (when they're
    nearer in time to the event than an available MCC TLE).
    However my finding, after the fact- using Rob's SkyMap 6.6, which normally is in
    extremely close agreement with my WorldView-generated ground tracks- is that the
    MCC computed track was about 225 meters SSE of the actual path, while a likely
    OIG computed ground track would have been about 140 meters NNW of the actual
    path; Tomás' uncle's patio was only about 65 meters NNW of the actual path!
    And in fact, for about 25 milliseconds, the main solar panels of the ISS- as
    well as a bit more of it- passed directly between Tomás, Gitka, and Zuzka, and
    the planetary disk of Venus!
    However, Arnold is indicating that, by his computations, the MCC TLE would have
    predicted a dead-hit from Tomás' location (and thus was 67 meters NNW of the
    actual path), while the OIG TLE nearest to the event (which actually corresponds
    to a time about 68 seconds after Tomás' observation, and so would not have been
    available for predictive purposes) would have predicted a path 2.4 Venus's (312
    meters) NNW of the actual path.
    By my analysis of Tomás' MapQuest map (combined with his transit photo), which
    was generated from CalSKY's prediction, the CalSKY prediction at the time was
    about 97 meters NNW of the actual transit path.
    The relevant TLEs are:
    1 25544U 98067A   04159.51929753  .00020000  00000-0  20000-3 0  9009
    2 25544  51.6330  15.0298 0005537 207.1571 152.9300 15.68796178 36803
    1 25544U 98067A   04160.18136574  .00014863  00000-0  13184-3 0  9471
    2 25544  51.6330  11.6482 0005508 205.6040 296.1391 15.68807781316908
    1 25544U 98067A   04160.34703704  .00014830  00000-0  13154-3 0  9486
    2 25544  51.6332  10.8038 0005500 206.3688 151.6668 15.68812729316928
    1 25544U 98067A   04160.42390752  .00014992  00000-0  13290-3 0  9491
    2 25544  51.6329  10.4117 0005395 206.7073 225.7658 15.68815833316945
    The observer location data is:
    48.2579° N (i.e., 48°15'28.6" N); 17.0272° E (i.e., 17°01'38" E); elevation 208
    meters (relative to the WGS84 ellipsoid).
    Some people may be interested in running this thru Guide 8.0, The Sky, etc., to
    see how their results compare.
    Walter Nissen had pointed out the coincidence of the date of the Venus transit:
    2004-06-08, and noted that Venus was in transit across the face of the Sun at:
       y  m  d  h  m  s
    2004-06-08 10 12 14.16182022... UTC
    Russell Eberst subsequently pointed out the "double coincidence" that last year,
    Mercury was in transit at:
       y  m  d  h  m  s
    2003-05-07 09 11 13.15171921...
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