LCROSS near Cor Caroli 6-29 7UT

From: Canopus56 (canopus56@yahoo.com)
Date: Sun Jun 28 2009 - 21:48:23 UTC

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    Tonight, the LCROSS satellite will pass between Cor Caroli (alf CvN) and M94 (for my o.p. at W110 N41) at around 7UT 2009.  Because there are no USPCMD two-line elements,topocentric plots can be generated using the NASA JPL Horizons emphermis generator. 
    http://ssd.jpl.nasa.gov/horizons.cgi
    
    It is uncertain whether the satellite will be too faint to image. Use 15 mags for image exposure planning. See chart at: 
    
    http://members.csolutions.net/fisherka/astronote/observed/LCROSS/CruiseFinder/20090629_0700_EQDetail.jpg 
    in http://canopus56.wikispaces.com/LCROSS_Cruise_Orbit
    
    I was able to generate a rough set of synthetic two line elements from the JPL Horizons orbital elements. However, the best interpolation was only good for 2 days (June 29 and 30) and maybe one or two degrees.
    
    LCROSS 
    1 35316U 09031B   09179.0000000  0.000383971 00000-0  00000-0 0    01
    2 35316 045.4778 070.491  2622329 016.6782 057.959  00.02527219    05
    
    Although inaccurate, it was not a wasted exercise.  Running the plotted path in animate mode in one of a satellite software packages, I notice that LCROSS at around 466,000km, unlike most lower fast moving satellites, has an parallax "hump" in its daily orbital path.  This appears to be related to realitively slow orbital movement of the satellite each night. The relative change of the observer on the Earth's rotating surface generates a slight parallax movement. 
    See graphic - apparent position of LCROSS satellite at 15 min intervals for 6-26-2009 to 7-1-2009 from W110 N41 observing point 
    
    http://canopus56.wikispaces.com/file/view/20090629LCROSSOrbitHump.jpg
    
    Clear skies - Kurt 
    
    
          
    
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