=============================================================================   
ROSETTA PCK Files                                                               
=============================================================================   
                                                                                
  This "aareadme.txt" file describes the contents of the KERNELS/PCK directory  
  of the ROSETTA SPICE data server. It also provides the file naming            
  conventions used for the ROSETTA PCK kernels, and it provides identification  
  of the most current version of each kind of PCK file.                         
                                                                                
  PCK files in this directory are either binary or text files. Text files are   
  created manually with the information from mainly the 2000 IAU Report,        
  with the exception of the Rosetta Asteroid Targets (Lutetia and Steins),      
  with information was obtained from "The Rosetta Asteroid Targets" paper       
  [Ref 4]. Binary files are created from the information contained in the       
  EOP files provided by IERS.                                                   
                                                                                
  All binary PCK files (*.BPC) contained in this directory are unix binary      
  files. These may be used as is (without format conversion) in a non-unix      
  environment by using any recent version of the SPICE Toolkit (Version N0052   
  or later). [Ref 2a]                                                           
                                                                                
  All text PCK files (*.TPC) contained in this directory are unix text files.   
  These may be used in a non-compatible text environment by using the ASCII     
  mode of FTP to port the files. [Ref 2a]                                       
                                                                                
  Contact Marc Costa Sitja (mcosta@sciops.esa.int) or the ESA SPICE Service 
  (esa_spice@sciops.esa.int) if you have any questions. 

                                                                                
=============================================================================   
References                                                                      
=============================================================================   
                                                                                
  1. PCK Required Reading. NAIF Document No. 254.05                             
                                                                                
  2. Selected SPICE Tutorials from the NAIF server:                             
ftp://naif.jpl.nasa.gov/pub/naif/toolkit_docs/Tutorials/office/individual_docs/ 
                                                                                
       a) Porting Kernels Tutorial     09_porting_kernels.ppt                   
       b) PCK Tutorial                 16_pck.ppt                               
                                                                                
  3. NAIF IDs Required Reading. NAIF Document No. 219.12                        
                                                                                
  4. "The Rosetta Asteroid Targets", M. A. Barucci, Padova.  31 Jan 2006        
       

=============================================================================   
Rosetta PCK Directory Structure                                                 
=============================================================================   

  aareadme.txt        Text file describing the directory structure, the naming  
                      conventions for the PCK, and the current version(s) of    
                      each PCK type.                                            
                                                                                
  former_versions     Subdirectory that contains obsolete versions of the PCK   
                      files that have been updated in the Current PCK Kernel    
                      Set.                                                      
      

=============================================================================   
Rosetta Binary PCK Naming Convention          EARTH_[sdat]_[edat]_[pdat].BPC    
=============================================================================   
                                                                                
      token           description                                               
      ---------       -------------------------------------------------------   
       [sdat]         Coverage start time of the file in YYMMDD format.         
                                                                                
       [edat]         Coverage end time of the file in YYMMDD format.           
                                                                                
       [pdat]         Start time for the predicted data in the file in YYMMDD   
                      format.                                                   
  

=============================================================================   
Current PCK Kernels Set                                                         
=============================================================================   
                                                                                
 Name                            Comments                                       
 ------------------------------  --------------------------------------------   
 EARTH_[sdat]_[edat]_[pdat].BPC  PCK file containing the orientation of the     
                                 Earth as a function of time for the interval   
                                 [sdat] to [edat]. From [pdat] the information  
                                 contained in the file corresponds to           
                                 predicted data. The rotational effects         
                                 included are precession, nutation, rotation    
                                 through true siderial time, polar motion and   
                                 nutation corrections.                          
                                                                                
 DE403_MASSES.TPC                PCK file containing the masses for the sun,    
                                 planets, satellites and planetary barycenters  
                                 These masses are given as ratios to of Solar   
                                 GM to barycenter GM.                           
                                                                                
 PCKvvvvv.TPC                    PCK file containing the size, shape, radii     
                                 and orientation constants for planets,         
                                 satellites, Sun and some asteroids.            
                                                                                
 ROS_CGS_RSOC_Vvv.TPC            PCK containing values for the pole             
                                 orientation, rotation period and shape for the 
                                 comet Churyumov-Gerasimenko. Please refer to   
                                 the metadata in the kernel for information     
                                 about the information sources used.      

 ROS_CG_RAD_Vvv.TPC              Contains the "Cheops reference" radii values 
                                 for 67P/C-G. This file should be loaded when
                                 using DSKs in order to make use of
                                 all DSK API capabilities.      
                                                                                
 ROS_LUTETIA_RSOC_Vvv.TPC        PCK file containing values for the pole        
                                 orientation, rotation period and shape         
                                 obtained for the Asteroid 21 Lutetia. Please   
                                 refer to the metadata in the kernel for        
                                 information about the information sources used.
                                                                                
 ROS_STEINS_Vvv.TPC              Preliminary PCK file containing draft values   
                                 for the rotation period and shape obtained     
                                 from ESA Science/Rosetta pages for the         
                                 Asteroid 2867 Steins and placeholder values    
                                 for pole direction (set arbitrarily to line    
                                 up with the ecliptic north pole in J2000       
                                 coordinates.)                                  
                                                                                                                                           
                                                                                
-------------------                                                             
                                                                                
        This file was last modified on Marc. 30, 2016 (M. Costa)


End of aareadme file.