KPL/PCK

Asteroid Donaldjohanson P_constants (PcK) SPICE kernel file
===========================================================================
 
   This text PCK contains rotational and ellipsoidal shape constants
   for asteroid Donaldjohanson.
 
Version and Date
--------------------------------------------------------
 
   Version 1.1 -- June 4, 2025 -- Stefano Mottola, Frank Preusker DLR
      
      First post-encounter Donaldjohanson PCK released for official use by 
      Lucy project. Pole direction, spin period and radii are derived from 
      LLORRI imagery and reported in [2]. 
     
   Version 1.0 -- April 20, 2021 -- Matt Barnes, NAIF/JPL
 
      This is the first Donaldjohanson PCK released for official use by 
      Lucy project. It contains values for the pole direction, rotation 
      period and shape from [1].
     
 
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 ``Version and Date`` if you modify
   the file.
 
 
 
Sources
--------------------------------------------------------
  
   The sources for the constants listed in this version of this file
   are:
  
     1) Lucy_Trojan_Target_PCK_Updates_19Apr2021.txt
        Provided by David Kaufmann, SWRI, 2021 April 20
 
     2) Donaldjohanson encounter paper.
        (Marchi et al., Science 2025, in prep.)
 

Orientation constants for asteroid Donaldjohanson
--------------------------------------------------------
 
   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 Donaldjohanson is 20052246. See the NAIF_IDs
   required reading for further information on NAIF integer codes.
 
   Prime meridian location coincides with our present best knowledge of 
   the intersection of the principal axis of least inertia with the shape.
   
   Pole RA, DEC and W0 are given in degrees, rate W1 in degrees/day.

   The LONG_AXIS keyword providing the offset between the longest axis
   of the triaxial ellipsoid used to model Donaldjohanson and the 
   Donaldjohanson prime meridian is not used by SPICE geometry 
   software. It is considered deprecated and provided solely for 
   backwards compatibility.

      \begindata
      
           BODY20052246_POLE_RA   = (  -35.33885    0.000          0.000 )
           BODY20052246_POLE_DEC  = (   50.95721    0.000          0.000 )
           BODY20052246_PM        = (  293.17865   34.409504086    0.000 )
           BODY20052246_LONG_AXIS = (    0.0                             )

      \begintext

Radii for asteroid Donaldjohanson
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   Values are given in km.

      \begindata

         BODY20052246_RADII     = (     4.4    2.2     1.55  )
 
      \begintext


End of PCK file.