PDS_VERSION_ID          = PDS3
RECORD_TYPE             = STREAM

OBJECT                  = TEXT
   INTERCHANGE_FORMAT   = ASCII
   PUBLICATION_DATE     = 2019-11-21
   NOTE                 = "PC-Kernel Information"
END_OBJECT              = TEXT

END


General information about SPICE PC-kernels
==========================================

   In the SPICE system, the PCK kernel provides orientation and shape
   information pertaining to extended solar system bodies such as the
   Sun, the planets, the natural satellites of the planets, comets, and
   asteroids. The most recent PC kernel file can always be obtained
   from NAIF/JPL.

   The purpose of the PCK kernels and associated software is to provide
   SPICE users with a convenient mechanism for supplying planetary
   physical constants to application programs. SPICE PCK routines are
   able to read files conforming to the PCK format and return to a
   calling application program both the data contained in such files
   and a small number of commonly used numeric quantities derived from
   the kernel data. For information on the SPICE toolkit and/or how to
   obtain it, please consult SPICE_INST.CAT and SOFT.CAT.

   Refer to the PCK.REQ document provided with the Toolkit to get more
   information on how to access PC-kernel data.


SELENE PCK Files
================

   This file describes the contents of the DATA/PCK directory of the
   SELENE SPICE dataset.

   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. 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).

   All text PCK files (*.TPC) contained in this directory are unix
   text files.  In order to be used in a non-UNIX environment, they have to
   be converted to the appropiate end-line convention. For example, the
   lines have to be terminated by a <CR><LF> combination for Windows
   platforms.


Current PC-Kernels Contained in this Data Set
=============================================

   The following PCK-kernels are provided in this data set:


     pckVVVVV.tpc                    PCK file containing the size, shape,
                                     radii and orientation constants for
                                     planets, satellites, Sun and some
                                     asteroids.

     moon_pa_de421_1900-2050.bpc     containing the Moon orientation
                                     consistent with DE421
 
   Note that when several versions of the same PCK kernels are provided in
   the dataset, the most recent one supersedes all the others.


Kernel File Details
===================

   The most detailed description of the data in a text PCK file is
   provided in metadata included inside the description area of
   the file. This information can be viewed using any text editor
   program.

   For a binary PCK kernel, this information can be viewed using
   utility programs COMMNT and SPACIT included into the NAIF Toolkit.

   At least a basic knowledge of the SPICE system is needed in
   order to use this kernels. The SPICE toolkit provides versions
   in Fortran (SPICELIB), C (CSPICE) and IDL (icy), and the user
   can choose any one that suits him/her.

   The SPICELIB routine FURNSH, CSPICE function furnsh_c, and icy
   routine cspice_furnsh load a kernel file into the kernel pool
   as shown below.

      CALL FURNSH ( 'kernel_name' )
      furnsh_c    ( ''kernel_name'' );
      cspice_furnsh, 'kernel_name'

   In the case when two or more files contain data overlapping in
   time for a given object, for binary kernels, the file loaded
   last takes precedence.

   If two (or more) text kernels assign value(s) using the '='
   operator to identical keywords, the data value(s) associated
   with the last loaded occurrence of the keyword are used -all
   earlier values have been replaced with the last loaded
   value(s).