Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Fri Nov 20 17:06:24 PST 2009 Objects in the Ephemeris -------------------------------------------------------- This SPK file contains ephemeris data for the Mars Reconnaissance Orbiter (MRO) spacecraft. The NAIF ID code for MRO is -74. Approximate Time Coverage -------------------------------------------------------- This file covers the following part of the Extended Science Phase of the MRO mission (orbits 13726 through 14906): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2009 JUL 01 00:01:06.184 2009 OCT 01 01:01:06.182 Status -------------------------------------------------------- This file was created by merging regular reconstructed OD solution SPK files produced by the MRO NAV team during the Extended Science Phase of the mission. This file was created by NAIF for archiving in the Planetary Data System (PDS). Pedigree -------------------------------------------------------- The original SPK files used to create this file contained only reconstructed trajectory. They were officially delivered to the MRO project data base by the MRO NAV team. The list of the original files data from which has been merged into this file is provided in Appendix 1 of these comments. Segment Boundary Discontinuities -------------------------------------------------------- This SPK file contains a large number of SPK segments that came from original individual SPK files. Although, each segment provides continuous trajectory within the interval that it covers, in general a position and velocity discontinuity exists at the boundary of the segment and the segments whose coverages immediately precede or follow it. The times and magnitudes of these discontinuities are provided in Appendix 2 of these comments. Usage -------------------------------------------------------- This file should be used together with DE414 planetary ephemeris and MAR063 satellite ephemeris since the original SPK files contained subsets of these particular ephemeris in them. Contacts -------------------------------------------------------- If you have questions regarding this data contact Boris V. Semenov (818)-354-8136 Boris.Semenov@jpl.nasa.gov Appendix 1: Original SPK List -------------------------------------------------------- The original SPK files, the data from which has been included into this file, are: spk_psp_rec13801_13621_13801_r-v1.bsp spk_psp_rec13896_13801_13896_r-v1.bsp spk_psp_rec13970_13895_13970_r-v1.bsp spk_psp_rec14077_13969_14077_r-v1.bsp spk_psp_rec14162_14076_14162_r-v1.bsp spk_psp_rec14224_14155_14224_r-v1.bsp spk_psp_rec14345_14224_14345_r-v1.bsp spk_psp_rec14438_14344_14438_r-v1.bsp spk_psp_rec14505_14437_14505_r-v1.bsp spk_psp_rec14609_14505_14609_r-v1.bsp spk_psp_rec14683_14608_14683_r-v1.bsp spk_psp_rec14793_14681_14793_r-v1.bsp spk_psp_rec14880_14792_14880_r-v1.bsp spk_psp_rec14966_14879_14966_r-v1.bsp Appendix 2: Segment Boundary Discontinuity Summary -------------------------------------------------------- This SPK file contains a large number of SPK segments that came from original individual SPK files. Although, each segment provides continuous trajectory within the interval that it covers, in general a position and velocity discontinuity exists at the boundary of the segment and the segments whose coverage immediately precede and follow it. The times and magnitudes of these discontinuities are provided in the table included in this Appendix. The top portion of the table contains the name of this SPK file. All descriptive lines in the top portion of the file start with the ``#'' character to allow direct plotting of the data in the freeware ``gnuplot'' application. The table consists of 5 columns. The first column is the orbit number within which a segment boundary with discontinuity occurs. The next column contains the UTC time of that segment boundary. The last three columns (3..5) contain view coordinate frame components -- ``down track'' (this direction is parallel to the velocity vector), ``normal to plane'' (this direction is computed as cross product of position vector by velocity vector) and ``in plane'' (this direction is computed as a cross product of ``down track'' by ``normal to plane'') -- of the difference between the state vectors computed at that UTC time defining segment boundary at which a discontinuity exists. The pairs of segments and discontinuity times are determined using an algorithm that emulates the standard SPK loading priority -- ``last loaded segment takes precedence''. Therefore, the discontinuities summarized in the file are those which a user reading file would actually see. The difference components in the view coordinate frame were computed for each discontinuity using the following algorithm: -- A single state was computed from each pair of segment the J2000 frame at the time of discontinuity. -- For this pair of states, a position difference vector was computed by subtracting the state computed from the segment with higher priority from the state computed from segment with lower priority. Then, a frame transformation matrix rotating these difference vectors from J2000 to the view coordinate frame defined by the state obtained from the higher priority segment was computed, and the position difference vector was rotated to the view frame coordinates using this matrix. The segment boundary discontinuities for this file are: # # Summary of discontinuities at segment boundaries for # SPK file ./mro_psp12.bsp: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 13742 2009-07-02T06:26:53.815 0.000 -0.000 0.000 13764 2009-07-03T23:46:53.815 -0.000 0.000 0.001 13783 2009-07-05T11:18:53.816 0.000 -0.000 -0.002 13801 2009-07-06T20:50:53.816 -0.000 0.000 0.002 13815 2009-07-07T22:54:53.816 -0.000 -0.000 0.002 13834 2009-07-09T10:18:53.816 0.000 0.000 -0.002 13853 2009-07-10T21:50:53.816 -0.000 -0.000 0.001 13873 2009-07-12T11:13:53.816 0.000 0.000 -0.003 13895 2009-07-14T04:28:53.816 -0.000 -0.000 0.002 13913 2009-07-15T14:09:53.816 -0.000 -0.000 0.001 13931 2009-07-16T23:43:53.816 0.000 0.000 -0.001 13951 2009-07-18T12:58:53.816 0.000 0.000 0.000 13969 2009-07-19T23:10:53.816 -0.000 0.000 -0.001 13985 2009-07-21T05:03:53.816 0.000 0.000 -0.001 14004 2009-07-22T16:38:53.816 -0.000 0.000 0.000 14019 2009-07-23T20:25:53.816 -0.000 -0.000 0.002 14038 2009-07-25T08:27:53.816 0.000 -0.000 -0.001 14059 2009-07-26T23:13:53.816 -0.000 0.000 0.001 14076 2009-07-28T06:53:53.816 -0.000 -0.000 0.002 14095 2009-07-29T18:34:53.816 -0.000 -0.000 0.007 14115 2009-07-31T07:57:53.816 0.000 -0.000 -0.006 14133 2009-08-01T17:41:53.816 -0.000 -0.000 0.003 14155 2009-08-03T10:38:53.816 0.000 -0.000 -0.005 14176 2009-08-05T02:08:53.816 0.000 0.000 -0.006 14195 2009-08-06T14:03:53.816 -0.004 -0.004 -0.000 14210 2009-08-07T17:18:53.816 -0.000 -0.000 0.004 14224 2009-08-08T19:48:53.816 -0.000 -0.000 -0.000 14244 2009-08-10T09:13:53.816 -0.000 -0.000 0.008 14266 2009-08-12T02:22:53.816 -0.000 -0.000 0.004 14286 2009-08-13T15:48:53.817 0.000 0.000 -0.007 14309 2009-08-15T10:46:53.817 -0.000 -0.000 0.005 14328 2009-08-16T22:19:53.817 -0.000 -0.000 0.007 14344 2009-08-18T04:03:53.817 0.000 0.000 -0.007 14362 2009-08-19T14:23:53.817 -0.000 -0.000 -0.010 14379 2009-08-20T21:31:53.817 -0.000 -0.000 0.067 14401 2009-08-22T14:52:53.817 -0.000 -0.000 -0.028 14418 2009-08-23T22:37:53.817 -0.000 0.000 -0.051 14437 2009-08-25T10:03:53.817 0.000 0.000 0.006 14451 2009-08-26T12:53:53.817 0.003 -0.000 0.012 14469 2009-08-27T22:00:53.817 0.000 -0.000 0.016 14478 2009-08-28T14:51:53.817 -0.000 0.000 -0.007 14491 2009-08-29T15:09:53.817 0.000 -0.000 0.011 14505 2009-08-30T17:20:53.817 0.000 0.000 0.014 14521 2009-08-31T23:15:53.817 0.000 -0.000 0.016 14538 2009-09-02T07:04:53.817 -0.000 0.000 -0.009 14558 2009-09-03T20:26:53.817 -0.000 0.000 -0.006 14578 2009-09-05T09:51:53.817 -0.000 -0.000 -0.001 14590 2009-09-06T08:18:53.817 0.000 -0.000 0.008 14608 2009-09-07T17:48:53.817 -0.000 0.000 -0.002 14628 2009-09-09T07:13:53.817 0.000 -0.000 0.004 14647 2009-09-10T18:48:53.817 0.000 -0.000 0.002 14664 2009-09-12T02:33:53.817 0.000 0.000 0.000 14681 2009-09-13T10:38:53.817 -0.000 0.000 -0.000 14699 2009-09-14T20:19:53.817 -0.000 0.000 -0.001 14719 2009-09-16T09:43:53.817 -0.000 0.000 -0.002 14738 2009-09-17T21:16:53.817 -0.000 -0.000 -0.004 14757 2009-09-19T08:35:53.817 0.000 -0.000 0.003 14773 2009-09-20T14:30:53.817 -0.000 -0.000 -0.008 14792 2009-09-22T01:48:53.817 -0.000 -0.000 0.001 14810 2009-09-23T11:28:53.817 0.000 -0.000 0.001 14823 2009-09-24T11:48:53.817 -0.000 0.000 -0.005 14841 2009-09-25T21:28:53.817 0.000 0.000 -0.001 14860 2009-09-27T08:58:53.817 0.000 0.000 0.001 14879 2009-09-28T20:38:53.817 -0.000 -0.000 -0.004 14898 2009-09-30T08:38:53.817 -0.000 0.000 -0.001