Description of the GASKELL TETHYS SHAPE MODEL bundle V1.0
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Bundle Generation Date: 2020-02-28
Peer Review: 2013 Asteroid Review, Fri Jun 14 00:00:00 MST 2013               
Discipline node: Small Bodies Node


Content description based on the data set catalog file description for the PDS3 version, CO-SA-ISSNA-5-TETHYSSHAPE-V1.0
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Note: for PDS3 data sets migrated to PDS4, the following text is taken
verbatim from the data set description and confidence level note of the
PDS3 data set catalog file. In these cases, some details may not be correct
as a description of the PDS4 bundle.
                                                           
                                                                              
  This shape model of Tethys is based on 814 Cassini ISSNA and 6 Cassini ISSWA
  images taken in the years 2004-2010.                                        
                                                                              
  Coordinate system:                                                          
                                                                              
  BODY603_POLE_RA      = (    40.66    -0.036      0.  )                      
  BODY603_POLE_DEC     = (   +83.52    -0.004      0.  )                      
  BODY603_PM           = (    10.45  +190.6979085  0.  )                      
  BODY603_LONG_AXIS    = (     0.                      )                      
  BODY603_NUT_PREC_RA  = ( 0. 0. 0.  +9.66   0.    0.  0.  0.  0. )           
  BODY603_NUT_PREC_DEC = ( 0. 0. 0.  -1.09   0.    0.  0.  0.  0. )           
  BODY603_NUT_PREC_PM  = ( 0. 0. 0.  -9.60  +2.23  0.  0.  0.  0. )           
                                                                              
  (For help in interpreting the values of the SPICE assignments above, see the
  document 'PCK Required Reading' (PCK.REQ), available at NAIF and in the     
  document directory of this data set.)                                       
                                                                              
  The parameters of the model are as follows:                                 
                                                                              
  Number of landmarks:  2457                                                  
  RMS position uncertainty:  313 m/dof (degree of freedom)                    
  Pointing uncertainty:  .431 mrad                                            
  Pointing residual:  .211 mrad                                               
  Number of observations:  150361                                             
  Observations per landmark:  61.2                                            
  RMS landmark location residual:  618 m/dof                                  
                                                                              
  The models were originally prepared in the Implicitly Connected             
  Quadrilateral (ICQ) format.  Vertex-facet format versions, derived from the 
  ICQ versions, are also provided.  The filenames are tethys_quad512q.tab and 
  tethys_ver512q.tab, where 512 is the value of Q (an indicator of the        
  resolution).  Files with three selections of lower resolution are also      
  provided for each format, with similar filenames but lower values of q.     
                                                                              
  The file 'tethysimagelist.tab' is a list of the Cassini ISSNA and ISSWA     
  images used to generate this model.  These images are archived in PDS under 
  the data set ID CO-S-ISSNA/ISSWA-2-EDR-V1.0.                                
                                                                              
  A text file, 'icqmodel.asc' is provided in the 'document' directory which   
  describes the ICQ format and the derivation of the vertex-facet versions.   
  For additional information about the shape models, see Gaskell et al.       
  (2008).                                                                     
                                                                              
  References                                                                  
  ==========                                                                  
                                                                              
  Gaskell, R.W., O.S. Barnouin-Jha, D.J. Scheeres, A.S. Konopliv, T. Mukai, S.
  Abe, J. Saito, M. Ishiguro, T. Kubota, T. Hashimoto, J. Kawaguchi, M.       
  Yoshikawa, K. Shirakawa, T. Kominato, N. Hirata, and H. Demura,             
  Characterizing and navigating small bodies with imaging data, Meteoritics   
  and Planetary Science, vol. 43, Issue 6, p. 1049-1061, 2008.


Known issues or problems with the data
======================================

  Note that the vertex-facet versions of the model have some duplicate        
  vertices on the edges and corners of the cube.  The duplicate vertices are  
  not used in the facet table, resulting in the presence of some vertices in  
  the vertex table which do not appear in the facet table.  This does not     
  affect the correctness of the vertex-facet version.

PDS3 Source
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Version 1.0 of this bundle was migrated from version 1.0 of the PDS3 data set CO-SA-ISSNA-5-TETHYSSHAPE-V1.0.