 
 
CLEMENTINE Spacecraft Trajectory SPK file, NRL Solution
===========================================================================
 
     Created by Bernard Kaufman and Richard Campion, CLEMENTINE Spacecraft
     Operations Team, NRL, summer 1994. Minor modifications and comments by
     Boris Semenov, NAIF/JPL, March 8, 2007.
 
 
Objects in the Ephemeris
--------------------------------------------------------
 
     This file contains ephemeris data for the CLEMENTINE spacecraft (NAIF
     ID -40) with respect to the Moon in the J2000 inertial reference
     frame.
 
 
Approximate Time Coverage
--------------------------------------------------------
 
     This file covers the following time periods:
 
        Start of Interval (ET)      End of Interval (ET)
        ------------------------    ------------------------
        1994 JAN 26 00:01:00.184    1994 FEB 02 13:01:00.184
        1994 FEB 19 12:58:00.185    1994 MAY 03 13:01:00.185
        1994 MAY 04 03:31:00.185    1994 MAY 06 13:31:00.185
 
 
Status
--------------------------------------------------------
 
     This file contains the final version of the CLEMENTINE trajectory
     determined by the CLEMENTINE Spacecraft Operations Team, NRL and
     intended for use in support of the spacecraft operations, experiment
     data processing, and for archiving with the Planetary Data System
     (PDS).
 
 
Pedigree
--------------------------------------------------------
 
     The original version of this file called ``clemdef.bsp'' was created
     by Bernard Kaufman and Richard Campion, CLEMENTINE Spacecraft
     Operations Team, NRL, at the end of the mission, during the summer
     1994. While the original file was in use for over a decade after the
     end of mission, it went unnoticed that it had small blocks of grossly
     erroneous data spanning a few seconds at the beginning of each segment
     the file was made up of. This fact was discovered during the the
     analysis performed at the time of PDS archive preparation.
     Specifically, the original SPK returned incorrect data during these
     intervals:
 
        Start of Interval (ET)      End of Interval (ET)       Error, km
        ------------------------    ------------------------   ---------
        1994 FEB 01 22:22:00.000    1994 FEB 01 22:36:00.000     ~1850
        1994 FEB 26 11:20:00.000    1994 FEB 26 11:34:00.000      ~400
        1994 MAR 05 09:44:00.000    1994 MAR 05 09:58:00.000      ~200
        1994 MAR 12 08:08:00.000    1994 MAR 12 08:22:00.000      ~310
        1994 MAR 19 06:32:00.000    1994 MAR 19 06:46:00.000      ~230
        1994 MAR 26 04:56:00.000    1994 MAR 26 05:10:00.000      ~200
        1994 APR 02 11:05:00.000    1994 APR 02 11:19:00.000      ~310
        1994 APR 09 09:29:00.000    1994 APR 09 09:43:00.000      ~210
        1994 APR 16 07:53:00.000    1994 APR 16 08:07:00.000      ~400
        1994 APR 23 06:17:00.000    1994 APR 23 06:31:00.000      ~200
        1994 APR 30 04:41:00.000    1994 APR 30 04:55:00.000      ~440
 
     Since the original SPK was a type 9 file containing discrete states,
     identifying the cause of problem and correcting it was a straight
     forward task. The states from all segments were extracted into a text
     file, the ``offending'' states at the beginning of each segment were
     deleted, and the rest of states were converted back into a type 9 SPK
     with the same attributes as the original file using the MKSPK utility
     program.
 
 
Segment Boundary Discontinuities
--------------------------------------------------------
 
     Since this SPK file was created using MKSPK, the segment partitioning
     done by the program resulted in no discontinuities at the segment
     boundaries.
 
 
Contacts
--------------------------------------------------------
 
     If you have questions regarding this data contact
 
        Boris V. Semenov
        (818)-354-8136,
        Boris.Semenov@jpl.nasa.gov
 
 
