KPL/PCK

Asteroid Apophis P_constants (PcK) SPICE kernel file
===========================================================================
 
   This text PCK contains ellipsoidal shape constants
   for asteroid Apophis.
 
 
Version and Date
--------------------------------------------------------

   Version 1.0 -- July 26, 2021 -- Michael Nolan, University of Arizona
   
      Initial version released for official use by OSIRIS-Rex project,
      containing values for shape from [1] and [2]. The orientation
      constants are *not* defined in this file as it is
      non-principal-axis, and will be defined as a CK frame.

 
Disclaimer
--------------------------------------------------------
 
   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. NAIF suggests that you inspect this file visually before
   proceeding with any critical or extended data processing.
 
   NAIF requests that you update the ``by line'' and date if you modify
   the file.
 
 
Sources
--------------------------------------------------------
 
   The sources for the constants listed in this version of this file
   are:
 
     1) Marina Brozovic et al. (2018) Goldstone and Arecibo radar
     observations of (99942) Apophis in 2012-2013. Icarus, 300:115.

     2) P. Pravec et al. (2014). The tumbling spin state of (99942)
     Apophis. Icarus, 233:48.

Orientation constants for asteroid Apophis
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   Not Applicable. The orientation is defined as a CK frame APOPHIS_CK.


Radii for asteroid Apophis
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Values in Current Version 1.0

  The radii in this version are set based on following values from [1]
  and [2]: Using the 340m mean diameter from [1] and axis ratios from
  [2], the axes would be: 453 x 315 x 276

   The radii below are 1/2s of the polar and equatorial dimensions
   provided in kilometers.

\begindata

         BODY20099942_RADII      = (  0.2265       0.1575       0.1380 )

\begintext
 
 

End of PCK file.
