Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Fri Nov 7 15:48:41 PST 2014 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 37160 through 38340): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2014 JUL 01 00:01:07.184 2014 OCT 01 01:01:07.182 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_rec37241_37138_37241_r-v1.bsp spk_psp_rec37304_37237_37304_r-v1.bsp spk_psp_rec37390_37302_37390_r-v1.bsp spk_psp_rec37492_37388_37492_r-v1.bsp spk_psp_rec37580_37489_37580_r-v1.bsp spk_psp_rec37674_37577_37674_r-v1.bsp spk_psp_rec37757_37672_37757_r-v1.bsp spk_psp_rec37842_37754_37842_r-v1.bsp spk_psp_rec37891_37840_37891_r-v1.bsp spk_psp_rec38026_37890_38026_r-v1.bsp spk_psp_rec38124_38024_38124_r-v1.bsp spk_psp_rec38197_38123_38197_r-v1.bsp spk_psp_rec38290_38195_38290_r-v1.bsp spk_psp_rec38391_38288_38391_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_psp32.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 37172 2014-07-01T23:03:52.815 0.003 0.000 0.001 37189 2014-07-03T06:48:52.815 0.006 0.000 0.003 37205 2014-07-04T12:40:52.815 -0.004 -0.000 -0.002 37222 2014-07-05T20:27:52.816 0.003 -0.000 0.001 37237 2014-07-07T01:11:22.816 -0.006 0.000 0.003 37256 2014-07-08T12:02:22.816 -0.005 -0.000 -0.002 37272 2014-07-09T17:57:22.816 0.001 -0.000 0.001 37287 2014-07-10T22:00:22.816 0.003 -0.000 0.002 37302 2014-07-12T02:43:52.816 0.006 0.000 -0.003 37322 2014-07-13T15:33:52.816 -0.007 -0.000 -0.003 37337 2014-07-14T19:38:52.816 0.004 0.000 0.002 37353 2014-07-16T02:40:52.816 0.002 0.000 -0.000 37371 2014-07-17T10:59:07.816 -0.004 -0.000 -0.002 37388 2014-07-18T19:28:52.816 0.003 -0.000 -0.001 37409 2014-07-20T11:32:52.816 -0.006 -0.000 -0.001 37428 2014-07-21T21:49:52.816 0.006 0.000 0.002 37446 2014-07-23T07:29:52.816 -0.012 0.000 -0.004 37462 2014-07-24T13:15:52.816 0.005 0.000 0.002 37478 2014-07-25T19:20:52.816 -0.000 0.000 -0.000 37489 2014-07-26T16:18:52.816 -0.009 0.000 0.003 37509 2014-07-28T05:18:22.816 -0.008 -0.000 -0.003 37530 2014-07-29T20:33:52.816 0.005 -0.000 0.002 37550 2014-07-31T09:46:52.816 0.003 0.000 0.001 37564 2014-08-01T11:59:52.816 -0.003 0.000 -0.001 37577 2014-08-02T13:45:52.816 -0.001 0.000 -0.000 37594 2014-08-03T21:22:52.816 -0.009 0.000 0.000 37610 2014-08-05T02:11:52.816 -0.010 -0.000 -0.003 37623 2014-08-06T02:28:52.816 -0.005 0.000 -0.001 37640 2014-08-07T10:17:52.816 0.009 0.000 0.002 37658 2014-08-08T19:42:52.816 -0.015 -0.000 -0.006 37672 2014-08-09T22:36:52.816 0.005 0.000 -0.002 37692 2014-08-11T11:32:52.816 -0.002 0.000 -0.001 37709 2014-08-12T19:21:22.817 0.009 -0.000 0.002 37723 2014-08-13T21:09:22.817 0.009 -0.000 0.004 37739 2014-08-15T04:08:52.817 -0.000 -0.000 -0.000 37754 2014-08-16T08:52:22.817 0.005 -0.000 0.002 37772 2014-08-17T18:35:52.817 0.005 0.000 0.002 37791 2014-08-19T04:33:52.817 -0.003 0.000 -0.001 37812 2014-08-20T20:46:52.817 0.004 -0.000 -0.001 37829 2014-08-22T04:30:52.817 -0.003 0.000 0.001 37840 2014-08-23T00:36:52.817 -0.003 0.000 0.001 37859 2014-08-24T11:34:22.817 -0.002 0.000 -0.001 37874 2014-08-25T15:50:52.817 0.009 0.000 0.002 37890 2014-08-26T22:47:52.817 -0.002 -0.000 0.000 37910 2014-08-28T12:34:22.817 0.019 0.000 0.005 37919 2014-08-29T04:16:52.817 -0.008 0.000 0.001 37934 2014-08-30T08:01:52.817 -0.019 -0.000 -0.004 37953 2014-08-31T20:25:52.817 -0.015 0.000 0.004 37970 2014-09-02T04:09:22.817 0.003 0.000 -0.001 37987 2014-09-03T12:28:52.817 0.018 0.000 0.004 38007 2014-09-05T00:32:52.817 -0.001 0.000 -0.000 38024 2014-09-06T08:37:52.817 -0.010 0.000 0.001 38047 2014-09-08T03:31:52.817 0.007 -0.000 0.000 38059 2014-09-09T01:47:52.817 0.006 -0.000 0.001 38076 2014-09-10T09:35:52.817 0.005 -0.000 0.001 38092 2014-09-11T16:51:52.817 -0.017 -0.000 -0.003 38111 2014-09-13T03:02:52.817 0.005 -0.000 0.001 38123 2014-09-14T01:48:52.817 0.030 -0.000 -0.005 38145 2014-09-15T18:33:52.817 -0.013 0.000 -0.002 38162 2014-09-17T02:21:52.817 0.017 0.000 0.002 38180 2014-09-18T11:50:22.817 0.009 0.000 0.002 38195 2014-09-19T16:24:52.817 -0.017 0.000 0.002 38213 2014-09-21T01:45:52.817 0.018 0.000 0.002 38233 2014-09-22T16:27:52.817 0.006 0.000 0.001 38251 2014-09-24T00:48:52.817 -0.015 -0.000 -0.002 38274 2014-09-25T19:26:52.817 0.016 0.000 0.003 38288 2014-09-26T22:34:52.817 0.003 -0.000 -0.001 38307 2014-09-28T09:29:22.817 -0.007 -0.000 -0.001 38321 2014-09-29T11:43:52.817 -0.026 0.000 -0.001 38334 2014-09-30T12:08:52.817 0.005 -0.000 -0.000