Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Mon Aug 24 09:43:58 PDT 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 12559 through 13725): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2009 APR 01 00:01:06.185 2009 JUL 01 01:01:06.184 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_rec12631_12550_12631_r-v1.bsp spk_psp_rec12718_12630_12718_r-v1.bsp spk_psp_rec12812_12717_12812_r-v1.bsp spk_psp_rec12887_12811_12887_r-v1.bsp spk_psp_rec13002_12886_13002_r-v1.bsp spk_psp_rec13078_13001_13078_r-v1.bsp spk_psp_rec13167_13077_13167_r-v1.bsp spk_psp_rec13270_13166_13270_r-v1.bsp spk_psp_rec13341_13269_13341_r-v1.bsp spk_psp_rec13389_13340_13389_r-v1.bsp spk_psp_rec13513_13386_13513_r-v1.bsp spk_psp_rec13622_13512_13622_r-v1.bsp spk_psp_rec13719_13621_13719_r-v1.bsp spk_psp_rec13801_13621_13801_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_psp11.bsp: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 12570 2009-04-01T22:31:53.814 0.000 0.000 -0.001 12592 2009-04-03T15:38:53.814 -0.000 -0.000 0.000 12610 2009-04-05T01:28:53.814 0.001 -0.000 -0.001 12630 2009-04-06T16:08:53.814 -0.001 0.000 -0.000 12649 2009-04-08T03:38:53.814 0.000 0.000 -0.000 12665 2009-04-09T09:18:53.814 0.001 0.000 0.001 12679 2009-04-10T10:20:53.814 -0.001 0.000 0.002 12698 2009-04-11T21:53:53.814 0.001 0.000 -0.002 12717 2009-04-13T09:23:53.814 0.000 0.000 -0.001 12737 2009-04-14T22:46:53.814 -0.000 -0.000 0.001 12754 2009-04-16T06:33:53.814 0.000 0.000 -0.000 12769 2009-04-17T10:39:53.814 -0.000 0.000 0.001 12789 2009-04-19T01:39:53.814 -0.000 0.000 0.000 12811 2009-04-20T17:13:53.814 0.000 -0.000 -0.000 12828 2009-04-22T00:48:53.814 -0.000 -0.000 0.000 12847 2009-04-23T12:31:53.814 -0.001 0.000 0.002 12867 2009-04-25T01:55:53.814 0.000 0.000 -0.001 12886 2009-04-26T13:40:53.814 0.003 -0.000 -0.007 12902 2009-04-27T19:41:53.814 -0.000 -0.000 0.000 12918 2009-04-29T01:28:53.814 0.001 0.000 -0.001 12934 2009-04-30T07:43:53.814 -0.000 0.000 0.000 12954 2009-05-01T20:32:53.814 -0.000 -0.000 0.001 12974 2009-05-03T09:56:53.814 -0.000 -0.000 0.000 12981 2009-05-03T23:23:53.814 -0.000 -0.000 0.000 13001 2009-05-05T12:33:53.814 -0.000 -0.000 -0.000 13021 2009-05-07T02:35:53.814 -0.000 -0.000 -0.000 13034 2009-05-08T02:13:53.814 -0.000 0.000 0.000 13056 2009-05-09T19:18:53.814 0.000 0.000 -0.000 13077 2009-05-11T11:08:53.814 0.000 -0.000 0.000 13091 2009-05-12T13:13:53.814 -0.000 -0.000 0.000 13113 2009-05-14T06:18:53.814 -0.000 -0.000 0.000 13133 2009-05-15T19:38:53.814 -0.000 -0.000 0.001 13152 2009-05-17T06:59:53.814 0.000 0.000 -0.001 13166 2009-05-18T09:01:53.814 -0.001 0.000 0.002 13186 2009-05-19T22:26:53.814 -0.000 -0.000 0.001 13204 2009-05-21T08:06:53.814 0.000 0.000 -0.001 13217 2009-05-22T08:38:53.814 -0.000 0.000 0.000 13234 2009-05-23T16:33:53.814 -0.000 -0.000 0.000 13249 2009-05-24T20:28:53.814 -0.000 -0.000 -0.000 13269 2009-05-26T09:45:53.814 -0.000 -0.000 0.000 13287 2009-05-27T19:58:53.815 0.000 -0.000 0.000 13290 2009-05-28T01:02:13.815 -0.000 -0.000 0.002 13310 2009-05-29T14:18:53.815 0.000 -0.000 -0.001 13322 2009-05-30T12:38:53.815 0.000 0.000 -0.001 13340 2009-05-31T22:33:53.815 0.000 0.000 -0.000 13359 2009-06-02T10:06:53.815 0.000 0.000 -0.000 13372 2009-06-03T10:23:53.815 -0.000 -0.000 0.002 13378 2009-06-03T21:37:53.815 0.001 0.000 -0.006 13386 2009-06-04T12:29:53.815 -0.000 -0.000 0.001 13402 2009-06-05T18:23:53.815 -0.000 -0.000 0.001 13418 2009-06-07T00:19:53.815 -0.000 -0.000 0.005 13429 2009-06-07T20:53:53.815 -0.000 -0.000 0.001 13441 2009-06-08T19:18:53.815 0.001 0.000 -0.007 13449 2009-06-09T10:18:53.815 -0.000 0.000 0.000 13462 2009-06-10T10:38:53.815 -0.000 -0.000 0.001 13476 2009-06-11T12:52:53.815 0.000 0.000 -0.001 13494 2009-06-12T22:32:53.815 0.000 0.000 -0.000 13512 2009-06-14T08:28:53.815 -0.000 -0.000 0.000 13527 2009-06-15T12:28:53.815 -0.000 0.000 0.001 13547 2009-06-17T01:56:53.815 0.000 -0.000 -0.001 13565 2009-06-18T11:19:53.815 0.000 0.000 -0.000 13579 2009-06-19T13:30:53.815 -0.000 -0.000 0.001 13601 2009-06-21T06:38:53.815 0.000 -0.000 -0.001 13621 2009-06-22T19:53:53.815 -0.000 -0.000 0.000 13640 2009-06-24T07:28:53.815 -0.000 -0.000 0.001 13659 2009-06-25T18:58:53.815 0.000 0.000 0.000 13679 2009-06-27T08:31:53.815 -0.000 0.000 0.001 13695 2009-06-28T14:36:53.815 0.000 -0.000 -0.001 13719 2009-06-30T11:22:53.815 -0.000 -0.000 -0.000