=============================================================================
SMART-1 CK Files
=============================================================================

  Last update:  12 MAY 2006  

  This "aareadme.txt" file describes the contents of the KERNELS/CK
  directory of the SMART-1 SPICE data server.  It also provides the file 
  naming conventions used for the SMART-1 CK kernels, and it provides
  identification of the most current version of each kind of CK file.

  All these CK files are produced by an automated system located at ESTEC, 
  operated by the SMART-1 Science Operations Center (STOC). We have chosen
  to use the ESOC naming convention for CK files, which are converted from
  ESOC's DDID Attitude files. Although this convention doesn't seem very
  descriptive and holds some redundant information, it could be useful to
  use the same name style for the sake of consistency. Also, data handling
  performed by the STOC automated system will be easier and faster.

  The contents and time span covered by any CK file may be easily determined
  using the "brief" utility program available in all copies of the
  SPICE Toolkit. Examples of usage:  
     %ckbrief  <ck_file_name> <sclk_file_name> <lsk_file_name>

  This utility requires additionally a sclk file and a lsk file; use the 
  latest versions of these files.

  Descriptive information about how/why/when an CK file was created is 
  usually available in the "comment area" of the file. This may be viewed
  using the "commnt" utility program available in all copies of the SPICE
  Toolkit. Use the "-r" option to read the comments. Example:
    %commnt -r <ck_file_name>

  All binary CK files (*.BC) contained in this directory are unix binary
  files. These may be used as is (without format conversion) in a non-unix
  environment when using any recent version of the SPICE Toolkit (Version
  N0052 or later).  [Ref 3b]

  Contact Jorge Diaz del Rio (jdiaz@rssd.esa.int) or Joe Zender 
  (Joe.Zender@esa.int) if you have any questions.


=============================================================================
References
=============================================================================
    1. Data Delivery Interface Document (DDID)       Appendix H - FD 
       products Issue 3.0 (SM1-ESC-IF-5003)

    2. CK Required Reading. NAIF Document No. 174.08

    3. Selected SPICE Tutorials from the NAIF server:  
ftp://naif.jpl.nasa.gov/pub/naif/toolkit_docs/Tutorials/office/individual_docs

       a) CK Tutorial                 15_ck.ppt
       b) Porting Kernels Tutorial    09_porting_kernels.ppt

    4. NAIF IDs Required Reading. NAIF Document No. 219.12

  
=============================================================================
SMART-1 CK Directory Structure
=============================================================================
 aareadme.txt            Text file describing the directory structure, 
                         the naming conventions for the CKs, and the current
                         version(s) of each CK type.

 former_versions         Subdirectory that contains obsolete versions of the 
                         CK files that have been updated in the Current CK
                         Kernels Set.



=============================================================================
SMART-1 Spacecraft CK Naming Covention          ffff_yYYMMDDhhmmss_vvvvv.ee
=============================================================================


          token           description
          ------------    --------------------------------------------------
          ffff            Source Product Type Identifier: 
                             ATNS -- Predicted S/C attitude
       		      
          y               Data Type Identifier                      
       	       	             P -- Predicted data
          YYMMDDhhmmss    Coverage start time of the data contained
	                  in the ATNS file.
          vvvvv           version number
          ee              NAIF File Name Extension  -- "BC"  (binary C kernel)


=============================================================================
SMART-1 Solar Arrays CK Naming Convetion        SMART1_SA_YYMMDD_vvv.ee
=============================================================================


          token           description
          ------------    --------------------------------------------------
          YYMMDD          Coverage start date of the data contained
	                  in the CK file.
          vvv             version number
          ee              NAIF File Name Extension  -- "BC"  (binary C kernel)


=============================================================================
Current CK Kernels Set
=============================================================================

 Name                              Comments
 --------------------------------  -------------------------------------
 ATNS_PYYMMDDhhmmss_xxxxx.BC       Contains SMART-1 predicted attitude
                                   information covering the time span
                                   starting at the date YYMMDDhhmmss. This
                                   attitude information corresponds to the
                                   ESOC attitude file named:
                                   ATNS_FDLMMA_DAPYYMMDDhhmmss_xxxxx.SM1
                                   where xxxxx designates the version number.

 SMART1_SA_yymmdd_xxx.BC           Contains SMART-1 Solar Array orientation
                                   data covering the time span starting at
                                   the date yymmdd. This orientation data
                                   is computed from telemetry information.