 
 
Mars Global Surveyor Post-Mission 50-year Nominal Trajectory SPK file
===========================================================================
 
     Created by Boris Semenov, NAIF/JPL, January 24, 2007 from the data
     provided by Gerhard Kruizinga, MGS NAV.
 
 
Objects in the Ephemeris
--------------------------------------------------------
 
     This file contains ephemeris data for the Mars Global Surveyor (MGS)
     spacecraft. NAIF ID code for MGS is -94.
 
 
Approximate Time Coverage
--------------------------------------------------------
 
     This file covers 50 years starting at the end of the MGS mission:
 
        COVERAGE BEGIN TIME (TDB):   2006 NOV 02 05:30:00.000
        COVERAGE END TIME (TDB):     2056 NOV 03 06:30:00.000
 
 
Status
--------------------------------------------------------
 
     This file contains the post-mission 50-year nominal trajectory
     generated by the MGS NAV team at the end of the mission for archiving
     purposes (see the trajectory release form provided in Appendix 1).
 
 
Pedigree
--------------------------------------------------------
 
     The 50-year nominal trajectory was provided by the MGS NAV team to
     NAIF as NIO p-files, which were converted by NAIF to SPKs using the
     NIOSPK program. To reduce the volume of data -- total size of the SPKs
     was about 10 GB -- geometric states of the MGS relative to Mars
     Barycenter in J2000 frame were computed at 5 minute steps using the
     SPKs. These states were then ``packaged'' into a type 13 SPK file with
     interpolation degree 11 using the MKSPK program (see Appendix 2 for
     MKSPK setup). The type 13 SPK file (this file) was then compared to
     the original SPKs to ensure that the re-sampled trajectory reasonably
     matched the original trajectory. The comparison, done using the
     SPKDIFF program, showed that the trajectory provided by this file
     matched the original trajectory to better than 2 meters in position
     and better than 20 cm/sec in velocity at all times.
 
 
Usage
--------------------------------------------------------
 
     This file should be used together with DE403 planetary ephemeris
     because this version of ephemerides was used in the trajectory
     determination process.
 
 
Contacts
--------------------------------------------------------
 
     If you have any questions regarding this data contact
 
        Boris V. Semenov, NAIF/JPL,
        (818)-354-8136,
        bsemenov@spice.jpl.nasa.gov
 
     or members of MGS NAV team:
 
        Pat Esposito      (818)-393-1264, pasquale.esposito@jpl.nasa.gov
        Gerhard Kruizinga (818)-354-7060, Gerhard.L.Kruizinga@jpl.nasa.gov
        Eric John Graat   (818)-393-1289, eric.j.graat@jpl.nasa.gov
        Stuart Demcak     (818)-393-7961, stuart.demcak@jpl.nasa,gov
 
 
Appendix 1: 50-year NOMINAL Trajectory Release Form
--------------------------------------------------------
 
        MGS                 FILE RELEASE FORM
 
        Mission Name:       MARS_GLOBAL_SURVEYOR
        Spacecraft Name:    MARS_GLOBAL_SURVEYOR
 
        Directory:          /nav/mgs/dev/traj/mapping/mgs_10yr_nominal
        File Type:          P-File
        Files Start Time:   02-NOV-2006 05:30:00
        Files Stop Time:    03-NOV-2056 05:30:00
 
        File Names:
        p_061102-071102-061212_10yr_nominal.nio
        p_071102-081101-061212_10yr_nominal.nio
        p_081101-091101-061212_10yr_nominal.nio
        p_091101-101101-061212_10yr_nominal.nio
        p_101101-111101-061212_10yr_nominal.nio
        p_111101-121031-061212_10yr_nominal.nio
        p_121031-131031-061212_10yr_nominal.nio
        p_131031-141031-061212_10yr_nominal.nio
        p_141031-151031-061212_10yr_nominal.nio
        p_151031-161030-061212_10yr_nominal.nio
        p_161030-161103-061212_10yr_nominal.nio
        p_161030-171030-061214_10yr_nominal.nio
        p_171030-181030-061214_10yr_nominal.nio
        p_181030-191030-061214_10yr_nominal.nio
        p_191030-201029-061215_10yr_nominal.nio
        p_201029-211029-061215_10yr_nominal.nio
        p_211029-221029-061215_10yr_nominal.nio
        p_221029-231029-061215_10yr_nominal.nio
        p_231029-241028-061215_10yr_nominal.nio
        p_241028-241103-061215_10yr_nominal.nio
        p_241103-251103-061219_10yr_nominal.nio
        p_251103-261103-061219_10yr_nominal.nio
        p_261103-271103-061219_10yr_nominal.nio
        p_271103-281102-061219_10yr_nominal.nio
        p_281102-291102-061219_10yr_nominal.nio
        p_291102-301102-061219_10yr_nominal.nio
        p_301102-311102-061219_10yr_nominal.nio
        p_311102-321101-061219_10yr_nominal.nio
        p_321101-331101-061219_10yr_nominal.nio
        p_331101-341101-061219_10yr_nominal.nio
        p_341101-351101-061219_10yr_nominal.nio
        p_351101-361031-061219_10yr_nominal.nio
        p_361031-361103-061219_10yr_nominal.nio
        p_361031-371031-061220_10yr_nominal.nio
        p_371031-381031-061220_10yr_nominal.nio
        p_381031-391031-061220_10yr_nominal.nio
        p_391031-401030-061220_10yr_nominal.nio
        p_401030-411030-061220_10yr_nominal.nio
        p_411030-421030-061220_10yr_nominal.nio
        p_421030-431030-061220_10yr_nominal.nio
        p_431030-441029-061220_10yr_nominal.nio
        p_441029-451029-061220_10yr_nominal.nio
        p_451029-461029-061220_10yr_nominal.nio
        p_461029-471029-061220_10yr_nominal.nio
        p_471029-481028-061220_10yr_nominal.nio
        p_481028-491028-061220_10yr_nominal.nio
        p_491028-501028-061220_10yr_nominal.nio
        p_501028-511028-061220_10yr_nominal.nio
        p_511028-521027-061220_10yr_nominal.nio
        p_521027-531027-061220_10yr_nominal.nio
        p_531027-541027-061220_10yr_nominal.nio
        p_541027-551027-061220_10yr_nominal.nio
        p_551027-561026-061220_10yr_nominal.nio
        p_561026-561103-061220_10yr_nominal.nio
 
 
        Notes:
        ~~~~~
 
        * These P-Files are to be used for archive purposes only
 
        * NOTE: 50 year NOMINAL trajectory based on the 30-day predict
          solution delivered on 02-NOV-2006 (solution ID
          m_061102_OD34193-34197_34569_V1). No trajectory perturbations due
          to MGS loss of signal are modeled or otherwise included.  Multi
          year average used for along track acceleration to model drag. As
          of this date (1/23/2007) there have been no clearly identifiable
          images of the MGS spacecraft. Furthermore, it appears that MGS
          did not enter safe more after the anomaly occurred on 11/02/2006.
          Currently a NASA review board is investigating all aspects of the
          loss of the MGS spacecraft.
 
        * Reconstructed Orbits:  34193, ... , 34197
 
        * Predicted Orbits:      34198, ... , 258020
 
        * File Name Convention
 
          The basic filename convention is:
 
          p_yymmdd(1)-yymmdd(2)-yymmdd(3)_label.nio
 
          where
 
          yymmdd(1): start date of the orbit arc
          yymmdd(2): end date of the orbit arc
          yymmdd(3): production date of the orbit arc
          label    : specified by the user to indicate strategy/case ....
 
          example: p_061102-071102-061212_10yr_nominal.nio
 
        Prepared by:   Gerhard Kruizinga Tue Jan 23 09:03:56 PST 2007
        Approval:      Pat Esposito
 
 
Appendix 2: MKSPK Run-time ``Stamp'' and Setup File
--------------------------------------------------------
 
        *****************************************************************
        MKSPK RUN DATE/TIME: 2007-01-24T11:32:47
        MKSPK SETUP FILE:    mkspk_type13.setup
        MKSPK INPUT FILE:    mgs_50year_nominal.txt
        MKSPK OUTPUT FILE:   mgs_50year_nominal.bsp
        OUTPUT FILE STATUS:  NEW FILE
        *****************************************************************
 
 
        \begindata
           INPUT_DATA_TYPE   = 'STATES'
           OUTPUT_SPK_TYPE   = 13
           OBJECT_ID         = -94
           CENTER_ID         = 4
           REF_FRAME_NAME    = 'J2000'
           PRODUCER_ID       = 'NAIF'
           DATA_ORDER        = 'EPOCH X Y Z VX VY VZ'
           DATA_DELIMITER    = ' '
           LEAPSECONDS_FILE  = '/kernels/gen/lsk/naif0008.tls'
           EPOCH_STR_LENGTH  = 24
           LINES_PER_RECORD  = 1
           TIME_WRAPPER      = '# TDB'
           POLYNOM_DEGREE    = 11
           SEGMENT_ID        = 'MGS 50 YEAR NOMINAL TRAJECTORY; 01/23/07'
        \begintext
 
 
        *****************************************************************
 
 
