PDS_VERSION_ID          = PDS3
RECORD_TYPE             = STREAM

OBJECT                  = TEXT
   INTERCHANGE_FORMAT   = ASCII
   PUBLICATION_DATE     = 2006-03-13 
   NOTE                 = "E-Kernel Information"
END_OBJECT              = TEXT
                                                                     
END 

General information about SPICE E-kernels
=========================================

   The purpose of the Cassini Events (E) -kernel (EK) is to store
   science plans, instrument and spacecraft commands and status, and
   Imaging Science Subsystem (ISS) mechanical events that may be seen
   as interference in other science data.

   The means of accessing the EK data are provided via a collection
   of subroutines that are part of the SPICELIB library, the major
   component of the NAIF Toolkit, or via the SPICE system utility
   programs, such as INSPEKT. The subroutines can be integrated into a
   user's application program while the INSPEKT program can be used to
   view E-kernel information interactively. Information about obtaining
   the SPICE Toolkit is located in the "software" subdirectory of the
   main directory of this dataset. Note that for Toolkit versions prior
   to N59, a special version of INSPEKT should be downloaded from the
   ftp://naif.jpl.nasa.gov/pub/naif/CASSINI/misc/inspekt_cas directory
   for best performance.

   To use E-kernels with the INSPEKT program, a SPICE Leapseconds (LSK)
   kernel is required. An INSPEKT script, "inspekt.asc", containing
   useful queries can be found in the directory "document/ek".

   For more information about the Cassini implementation of E-Kernels,
   see the Software Interface Specification document in the directory
   "documents/ek".  Subsystem status information is described in the
   SEQGEN User's Guide in the same directory. For general information
   regarding E-Kernels, refer to the EK Required Reading (ek.req) and
   inspekt.ug documents provided with the Toolkit or available from the
   NAIF Node of the PDS.


Cassini E-kernels contained on this volume
==========================================

   This directory contains the SPICE E-Kernel files for the Cassini
   mission. All files are in IEEE big endian binary format and suitable
   for use on UNIX workstations and MACs. The following files are present
   in this directory.


Science Plan E-Kernels
-----------------------

   Science plan E-Kernels contain scientific objectives for observations
   scheduled over a specified period of time.

   Filenames for Science Plan EK files have the form:
  
        [Sequencenumber]_[Phase][v].bep

   where:

        [Sequencenumber]        is the 3 character sequence number,
                                e.g. "S02",

        [Phase]                 is a mission phase covered by the
                                science plan, e.g. "CIMSSOPUpdate" where
                                "CIMS" indicates the data was extracted
                                from the Cassini Information Management
                                System and "SOPUpdate" refers to the
                                Science Operations Plan Update phase.

        [v]                     is the version identifier, starting with
                                "a".


Command Database E-Kernels
--------------------------

   Command database E-Kernels contain command and parameter descriptive
   information used with Sequence EK files (see below).

   Filenames for Command Database EK files have the form:

        [cmdVersion].bdb

   where:

        [cmdVersion]            is the command database version,
                                e.g. "11A".


Sequence E-Kernels
-------------------

   Sequence E-Kernels contain spacecraft and instrument commands intended
   to carry out the observational science objectives of the mission
   (as partly described in the text component of the Science Plan),
   command notes, mechanical noise events, and spacecraft and instrument
   status information. Each of the last three items has its own type of
   file.

   Filenames for Sequence EK files have the forms:

        [Sequencenumber]_[Source]_[Key][v].bes  or
        
        [Sequencenumber]_36noise[v].bes
        
        [Sequencenumber]        is the 3 character sequence number,
                                e.g. "S02",

        [Source]                is either "cmd", indicating commands from
                                a Predicted Events File (PEF) or "status"
                                indicating status from a PEF,

        [Key]                   has the value "p" for Predicted Events
                                based upon a prepared sequence or "f"
                                for As-Flown Events with changes to the
                                planned sequence incorporated,

        [v]                     is the version string, e.g. "h_full".


Kernel file details
===================

   The most detailed description of the data in a binary EK file is
   provided in metadata included inside the comment area of the file.
   This information can be viewed using the utility programs COMMNT and
   SPACIT included in the NAIF Toolkit. The Toolkit is available from
   the NAIF website.


Contact information
===================

   Regarding Cassini project specific information provided in this
   data set and for general information about the SPICE system:
   
      Boris Semenov 
      (818)-354-8136 
      Boris.Semenov@jpl.nasa.gov
      
   or 
   
      Adrian W Tinio
      (818)-354-7511
      Adrian.W.Tinio@jpl.nasa.gov

   address:
   
      Navigation and Ancillary Information Facility (NAIF)
      Jet Propulsion Laboratory
      MS 301-125L
      4800 Oak Grove Drive
      Pasadena CA 91109 USA