MEX FK SPICE Kernels
  ====================


  This "aareadme.txt" file describes the contents of the kernels/fk directory
  of the MEX SPICE data server. It also provides the file naming conventions
  used for the MEX CK files.

  All these FK files are produced manually with the information supplied by
  Mars Express teams describing the frames for the spacecraft and its science
  instruments. Some of these FK files (for tracking stations) are provide
  specifically for the Radio Science investigation.

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

  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), IDL (icy) and Matlab (mice), and the user can choose any one that
  suits him/her.

  The SPICELIB routine FURNSH, CSPICE function furnsh_c, and icy and matlab
  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'
      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) ).

  All FK files (*.TF) contained in this directory are UNIX text files. These
  may be downloaded to a different system (Mac OS, Windows) by using the ASCII
  mode of FTP.

  Contact

      ESA SPICE Team             spice@sciops.esa.int

  , or

      Alfredo Escalante Lopez    aescalante@sciops.esa.int

  if you have any questions.


  References
  ==========

    1. Frames Required Reading (NAIF Document).

    2. NAIF IDs Required Reading (NAIF Document).

    All the NAIF Documents are available at the NAIF web:

      http://naif.jpl.nasa.gov


  Mars Express FK Directory Structure
  ===================================

    aareadme.txt          This file.

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

    EARTH_TOPO_YYMMDD.TF  SPICE Kernel (FK) that contains
                          definitions for the topocentric
                          reference frames for the Deep Space
                          Network (DSN) stations. This kernel
                          was released on YY-MM-DD.

    EARTHFIXEDIAU.TF      SPICE Kernel (FK) that contains
                          association that makes the IAU_EARTH
                          frame coincide with the earth fixed
                          reference frame.

    EARTHFIXEDITRF93.TF   SPICE Kernel (FK) that contains
                          association that makes the ITRF93
                          frame coincide with the earth
                          fixed reference frame.

    MEX_Vxx.TF            SPICE Kernel (FK) that contains the complete
                          set of frame definitions for the Mars Express
                          Spacecraft (MEX) and Beagle-2 Lander (BEAGLE2)
                          including definitions for the MEX fixed
                          and MEX science instrument frames and
                          BEAGLE2 fixed, and landing site local
                          frames. This kernel also contains NAIF
                          ID/name mapping for the MEX and BEAGLE2
                          instruments.

    MEX_DSK_SURFACES_Vvv.TF

                          SPICE Kernel (FK) that contains surface
                          name-ID mappings for the Mars Express
                          structures DSKs surfaces.

    MEX_PFS_ROIS_Vvv.TF   SPICE Kernel (FK) that contains a set of Mars
                          Express regions of interest locations frame
                          definitions for PFS.

    MEX_RELAY_LOCATIONS_Vvv.TF

                          SPICE Kernel (FK) that contains a set of Mars
                          Express relay locations frame definitions
                          for selected Rovers and Landers.

    MEX_SCI_Vvv.TF        SPICE Kernel (FK) that contains definitions
                          for a number of generic frames used by the
                          MEX mission for Science opportunities
                          identification, data analysis and scientific
                          research.

    ESTRACK_Vvv.TF        SPICE Kernel (FK) that contains definitions
                          for topocentric reference frames for each
                          of the ESA ESTRACK ground stations.

    EARTHSTNS_RU_YYYYMMDD.TF

                          SPICE Kernel (FK) that contains definitions
                          for topocentric reference frames for the
                          Russian ground stations.

    RSSDvvvv.TF           SPICE Kernel (FK) that contains definition
                          for a number of mission independent frames
                          that could be used by any of the users of
                          any of the ESA planetary missions and that
                          are not built in the SPICE toolkit. The
                          following frames related to Mars are
                          implemented: Mars Mean Equator of Date (MME),
                          Mars-centric Solar Orbital of Date (MSO) and
                          Mars Mean Equator of date J2000 (MME2000).


-------------------

        This file was last modified on March 22th, 2021. (R. Valles)


End of aareadme file.