PDS_VERSION_ID          = PDS3
RECORD_TYPE             = STREAM

OBJECT                  = TEXT
   INTERCHANGE_FORMAT   = ASCII
   PUBLICATION_DATE     = 2013-03-26
   NOTE                 = "This file describes the files in the 
                           extras directory of this archive."
END_OBJECT              = TEXT

END


Extra data related to the Cassini mission
=========================================

   This directory contains value added elements that are outside the
   scope of the PDS archive requirements. Items included in this
   directory are currently limited to the meta-kernels, orbit number
   files, the formal SPK position uncertainty tables (covariance matrix
   tables), and files with information relevant to image navigated
   C-Kernels as well as comparisons between predicted and reconstructed
   C-Kernels produced by AACS.

   The meta-kernels provided in the ``mk'' subdirectory contain
   complete lists the SPICE kernels in the format required by the main
   SPICE data loader routine FURNSH that need to be loaded into a
   SPICE-based application to compute geometry for a particular time
   period. For more information about the meta-kernels provided on this
   volume, see file ``mk/mkinfo.txt''.

   The orbit number files included in the ``orbnum'' subdirectory
   provide the orbit numbers and start times along with a small set of
   derived geometric parameters for each orbit. These files were
   generated using the NAIF's ORBNUM utility program for the spacecraft
   trajectory SPK files for the orbital phases of the mission. For more
   information about the orbit number files provided on this volume,
   see file ``orbnum/orbinfo.txt''.

   The files describing the formal position uncertainties of Cassini's
   reconstructed ephemeris provided in the SPK files produced by the
   CASSINI NAV Team can be found in the directory ``spkxtra'' and in
   subdirectories of that directory. For more detailed information, see
   the file ``spkxtra/spkxinfo.txt''.

   The files with information relevant to image navigated C-Kernels as
   well as comparisons between predicted and reconstructed C-Kernels
   produced by AACS can be found in the directory ``ckxtra'' and in
   subdirectories of that directory. For more detailed information,
   see the file ``ckxtra/ckxtinfo.txt''.


Contact Information 
===================

   Regarding Cassini project specific information provided in this data
   set and for general information about SPICE system, contact:
   
      Boris Semenov 
      (818)-354-8136 
      Boris.Semenov@jpl.nasa.gov
      
   address:
   
      Navigation and Ancillary Information Facility (NAIF)
      Jet Propulsion Laboratory
      MS 301-125L
      4800 Oak Grove Drive
      Pasadena CA 91109 USA