Deep Impact/EPOXI SCLK files.
===========================================================================

   This ``aareadme.txt'' file describes contents of the kernels/sclk
   directory of the Deep Impact/EPOXI SPICE data server. It was last
   modified on September 19, 2007. Contact Chuck Acton (818-354-3869,
   Chuck.Acton@jpl.nasa.gov) or Boris Semenov (818-354-8136,
   Boris.Semenov@jpl.nasa.gov) if you have any questions regarding this
   data.

EPOXI SCL-kernels Contained in This Directory
=============================================

   This directory contains the following Deep Impact Flyby (DIF)/EPOXI
   and SCLK files (only the leading portion of the file name is shown;
   the extension of all file names is ".tsc"):

      DIF_SCLKSCET.VVVVV          Regular DIF/EPOXI SCLK kernels
                                  generated from corresponding
                                  SCLKvSCET files


Deep Impact SCL-kernels Contained in This Directory 
===================================================

   This directory contains the following Deep Impact Flyby (DIF) and
   Deep Impact Impactor (DII) SCLK files (only the leading portion of
   the file name is shown; the extension of all file names is ".tsc"):

      dif_sclkscet_00015          "official" DIF SCLK kernel file. This
                                  SCLK kernel provides data for the
                                  primary (SCU A) DIF on-board clock
                                  based on the final correlation
                                  released at the end of the primary
                                  mission. This is the official SCLK
                                  file used by the ground system during
                                  mission operations.
                                  
      dif_sclkscet_00015_science  "improved" DIF SCLK kernel file. This
                                  SCLK kernel provides data for the
                                  primary (SCU A) DIF on-board clock
                                  based on the final correlation. This
                                  SCLK provides an improved correlation
                                  (as compared to the official SCLK)
                                  and is recommended to be used for
                                  post encounter data processing.

      dif_sclkscet_00010_scu_b    "SCU B" DIF SCLK kernel file. This
                                  SCLK kernel provides data for the
                                  secondary (SCU B) DIF on-board clock
                                  based on the final correlation
                                  released at the end of the primary
                                  mission. This SCLK must be used ONLY
                                  to process data that were stored on
                                  the SCU B side of the spacecraft.

      dii_sclkscet_00008          DII SCLK kernel file. This SCLK
                                  kernel provides data for the DII
                                  on-board clock based on the final
                                  correlation released prior to the
                                  encounter.

      dii_sclkscet_00008_science  DII SCLK kernel file. This SCLK
                                  provides modified correlation (as
                                  compared to the official SCLK)
                                  consistent with the final encounter
                                  trajectory solution by DI NAV and is
                                  recommended to be used for post
                                  encounter data processing.

   Note that only one of the three DIF SCLK files must be loaded into a
   user application at any given time because all three DIF SCLK
   kernels provide for the same clock ID, -140. The same applies to DII
   SCLK files -- only one of the two SCLK should be loaded at any given
   time.


EPOXI SCLK File Naming Scheme
=============================

   TBD


Deep Impact SCLK File Naming Scheme
===================================

   The Deep Impact SCLKs provided in this directory are named according
   to the following scheme:

      sc_sclkscet_VVVVV[_ident].tsc

   where:

      sc        is the name of the spacecraft: "dif" or "dii";

      sclkscet  is the literal script carried over from the source 
                SCLKvSCET file name;

      VVVVV     is the file version number;

      ident     is a token further identifying the data in the file
                (optional). Examples: "scu_b" for SCU B clock, etc.


Kernel File Details
===================
 
   The most detailed description of the data in an SCLK file is
   provided in metadata included inside the descriptive text areas
   within the file. This information can be viewed using any text
   editor.