Upcoming Milstar launch 1x "comet"

From: ecannon@mail.utexas.edu
Date: Wed Jan 08 2003 - 02:53:01 EST

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    A Milstar Titan IVB+Centaur launch is scheduled for 21:35 UTC/GMT 
    (16:35 EST, 15:35 CST, etc.) on Tuesday, January 21.  Previous 
    such Titan/Centaur launches have, several hours after the launch, 
    resulted in an artifical "comet" due to venting of excess fuel 
    from the Centaur.  I have been fortunate enough to see two of 
    these with Mike McCants, 97-068 to a Molniya-type orbit, and 
    Milstar 5 to a geostationary orbit.  (On another attempt the 
    weather prevented any observation by us.  Mike heroically drove a 
    couple of hundred miles around central Texas that night, with me 
    as passenger, trying to find even a small hole in the clouds.)  
    These "comets" are visible without magnification for quite a few 
    minutes -- and of course are even more interesting if seen with 
    magnification (including seeing other related events dump, such 
    as the objects slowly drifting apart after payload deployment)!
    Also, for the 2001 launch, Mike tracked the ascending Centaur 
    plus payload for several hours, during which time we observed a 
    few flashes, presumably due to slow spin-stabilization rotation.  
    (When the conditions permitted, Mike tracked the Centaur for a 
    few weeks, until it drifted too far west.)
    There is some discussion of previous such events, including the 
    Cassini launch, in these messages: 
    2001 Milstar
    1997 NRO
    1997 Cassini Centaur
    Rick Baldridge managed to get videography of the 2001 Milstar.
    Mike has one of Rick Baldridge's images on his site, under 
    "Image Intensifier Picture of Milstar 5 Centaur Fuel Dump".  
    There was also a video that may be available.
    Gordon Garradd photographed Cassini and its Centaur, along with 
    the then-faint associated cloud.  Small and large versions are 
    on the VSOHP near the end of this page:
    So, what I'm trying to say is that, based on past launches (i.e.,
    "caveat lector"), this could be a rare chance for observers in 
    the Americas to see (and photograph) an unusual phenomenon -- an 
    ephemeral artifical earth-orbit comet, plus related events if a 
    telescope is used.  
    Those from other continents who have unlimited budgets, free 
    times, and a certain level of optimism and enthusiasm might 
    even consider a visit to the mid-to-lower latitudes of this 
    hemisphere, between perhaps longitudes 70 and 130 west, for this 
    I should mention that reasonably good suggested search elements 
    will be required in order to have a good chance to track the 
    ascent, so we can only hope that someone or ones (You know who 
    you are.) might provide them.
    Ed Cannon - ecannon@mail.utexas.edu - Austin, Texas, USA
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