KPL/PCK

Comet Churyumov-Gerasimenko -- RSOC Solution
===========================================================================

 
Version and Date
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     Version 0.0 -- September 9, 2010 -- J. Vazquez, PSA, SRE-OS/ESA
 
 
Organization
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     The sections of this file are as follows.
 
     Introductory Information:
 
         --   Version description
 
         --   Disclaimer
 
         --   Sources
 
     Pck Data:
 
         --   Orientation constants for Asteroid 21 Lutetia
 
         --   Radii for Asteroid 21 Lutetia
 
 
Version description
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     This is a PCK containing values for the pole orientation, 
     rotation period and shape obtained from [2].
     
 
Disclaimer
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     This constants file may not contain the parameter values that you
     prefer. Note that this file may be readily modified by you or
     anyone else. PSA suggests that you inspect this file visually
     before proceeding with any critical or extended data processing.
 
     PSA requests that you update the version section if you modify
     the file.
 
 
Sources
--------------------------------------------------------
 
     The sources for the constants listed in this file are:
 
        1) ESA Science and Technology Server, Rosetta area,
           http://sci.esa.int/science-e/www/object/index.cfm?
           fobjectid=34849

        2) Hubble Space Telescope observations of the nucleus and inner
           coma of comet 67P/Churyumov-Gerasimenko, Lamy et al., June 2006
        
        


Orientation constants for Comet Churyumov-Gerasimenko.
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     The inertial reference frame for these constants is J2000; this is
     the default reference frame for PCK orientation data.
 
     The epoch of the constants is J2000; this is Julian ephemeris date
     (JED) 2451545.0.
 
     The NAIF integer code for Comet Churyumov-Gerasimenko is 1000012. See 
     the NAIF_IDs required reading for further information on NAIF integer
     codes.
 
     According to [2] the comet pole direction is specified by the 
     following ecliptic right ascension (RA) and declination (DEC):

        RA  =  40 deg.
        DEC =  70 deg.

     These parameters correspond to the following in the J2000 equatorial 
     frame:

        RA =  326.703 deg.
        DEC = 71.732 deg.

     The W1 term was set to correspond to the period of 12.7 hours,
     and the W0 term is arbitrarily set to 0.
     
     \begindata
 
        BODY1000012_POLE_RA             = (  326.703     0.0         0.0 )
        BODY1000012_POLE_DEC            = (  71.732      0.0         0.0 )
        BODY1000012_PM                  = (   0.0      680.315       0.0 )
 
     \begintext


Radii for Comet Churyumov-Gerasimenko
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     The radii provided in the keyword below correspond to the 
     following comet shape

          a/b/c = 2.28km/1.905km/1.72km

     provided in [2].
 
     \begindata
 
        BODY1000012_RADII               = ( 2.28  1.905  1.72 )
 
     \begintext


Albedo Values for Comet Churyumov-Gerasimenko
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     No values for the albedo are provided in [2].