Mars Reconnaissance Orbiter Primary Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Wed Nov 14 12:20:03 PST 2007 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 Primary Science Phase of the MRO mission (orbits 4346 through 5525): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2007 JUL 01 00:01:05.184 2007 OCT 01 01:01:05.182 Status -------------------------------------------------------- This file was created by merging regular reconstructed OD solution SPK files produced by the MRO NAV team during the Primary 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_rec04431_04330_04431_r-v1.bsp spk_psp_rec04550_04431_04550_r-v1.bsp spk_psp_rec04629_04548_04629_r-v1.bsp spk_psp_rec04712_04629_04712_r-v1.bsp spk_psp_rec04805_04712_04805_r-v1.bsp spk_psp_rec04907_04804_04907_r-v1.bsp spk_psp_rec04997_04907_04997_r-v1.bsp spk_psp_rec05092_04996_05092_r-v1.bsp spk_psp_rec05185_05091_05185_r-v1.bsp spk_psp_rec05265_05185_05265_r-v1.bsp spk_psp_rec05364_05265_05364_r-v1.bsp spk_psp_rec05450_05363_05450_r-v1.bsp spk_psp_rec05532_05449_05532_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_psp4.bsp: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 4360 2007-07-02T03:53:54.815 -0.000 0.000 -0.026 4378 2007-07-03T13:28:54.815 -0.000 0.000 -0.024 4395 2007-07-04T21:18:54.815 -0.000 -0.000 0.004 4411 2007-07-06T03:15:54.816 0.000 -0.000 0.011 4431 2007-07-07T16:33:54.816 0.000 -0.000 -0.000 4453 2007-07-09T09:53:54.816 0.000 0.000 -0.001 4470 2007-07-10T17:32:54.816 -0.000 0.000 -0.005 4488 2007-07-12T03:18:54.816 0.000 0.000 0.007 4503 2007-07-13T07:14:54.816 -0.001 -0.000 -0.008 4517 2007-07-14T09:37:54.816 0.000 -0.000 0.004 4532 2007-07-15T13:29:54.816 -0.000 0.000 -0.001 4548 2007-07-16T19:23:54.816 0.000 0.000 0.004 4566 2007-07-18T05:03:54.816 -0.000 -0.000 -0.001 4586 2007-07-19T18:33:54.816 0.000 0.000 0.007 4601 2007-07-20T22:40:54.816 -0.000 -0.000 0.000 4614 2007-07-21T23:31:54.816 0.000 0.000 0.001 4629 2007-07-23T03:13:54.816 -0.000 0.000 -0.001 4644 2007-07-24T06:55:54.816 -0.000 0.000 -0.004 4661 2007-07-25T14:43:54.816 0.000 0.000 0.002 4677 2007-07-26T20:38:54.816 0.000 0.000 0.003 4695 2007-07-28T06:18:54.816 -0.000 -0.000 -0.003 4712 2007-07-29T14:08:54.816 0.000 0.000 0.005 4731 2007-07-31T01:38:54.816 -0.000 -0.000 -0.000 4753 2007-08-01T18:46:54.816 -0.000 -0.000 -0.001 4774 2007-08-03T09:48:54.816 -0.000 -0.000 0.000 4793 2007-08-04T21:35:54.816 0.000 -0.000 0.002 4804 2007-08-05T18:08:54.816 -0.000 0.000 -0.000 4823 2007-08-07T05:42:54.816 -0.000 0.000 -0.001 4842 2007-08-08T17:14:54.816 -0.000 -0.000 0.000 4864 2007-08-10T10:23:54.816 0.000 -0.000 0.003 4886 2007-08-12T03:36:54.816 -0.000 0.000 -0.000 4907 2007-08-13T18:48:54.817 0.000 0.000 0.001 4924 2007-08-15T02:41:24.817 0.000 -0.000 0.003 4941 2007-08-16T10:28:54.817 0.000 0.000 0.000 4960 2007-08-17T21:56:54.817 0.000 -0.000 0.000 4977 2007-08-19T05:42:54.817 -0.000 -0.000 -0.001 4996 2007-08-20T17:13:54.817 0.001 0.000 0.003 5015 2007-08-22T04:48:54.817 -0.000 -0.000 -0.000 5034 2007-08-23T16:58:54.817 0.000 0.000 -0.000 5053 2007-08-25T03:53:54.817 -0.000 0.000 -0.000 5072 2007-08-26T15:28:54.817 0.000 0.000 0.000 5091 2007-08-28T03:05:54.817 0.000 -0.000 0.002 5112 2007-08-29T18:30:54.817 0.000 -0.000 0.002 5129 2007-08-31T02:05:54.817 0.000 0.000 0.000 5147 2007-09-01T11:40:54.817 -0.000 0.000 -0.001 5165 2007-09-02T21:20:54.817 -0.000 -0.000 0.000 5185 2007-09-04T10:45:54.817 -0.000 -0.000 0.000 5206 2007-09-06T02:06:54.817 -0.000 -0.000 -0.001 5227 2007-09-07T17:18:54.817 -0.000 -0.000 -0.001 5245 2007-09-09T03:03:54.817 -0.000 0.000 -0.000 5265 2007-09-10T16:41:24.817 -0.000 -0.000 -0.002 5284 2007-09-12T03:53:54.817 -0.000 0.000 -0.003 5305 2007-09-13T19:10:54.817 0.000 -0.000 0.001 5326 2007-09-15T10:26:54.817 -0.000 0.000 -0.001 5344 2007-09-16T20:10:54.817 0.000 0.000 0.002 5363 2007-09-18T07:43:54.817 -0.000 0.000 -0.003 5378 2007-09-19T11:41:54.817 -0.000 0.000 -0.003 5396 2007-09-20T21:23:54.817 -0.000 -0.000 0.001 5416 2007-09-22T10:46:24.817 -0.000 0.000 -0.001 5436 2007-09-24T00:11:24.817 -0.000 -0.000 -0.000 5449 2007-09-25T00:28:54.817 0.000 0.000 0.001 5467 2007-09-26T10:08:54.817 -0.000 -0.000 -0.000 5491 2007-09-28T07:18:54.817 -0.000 0.000 -0.001 5509 2007-09-29T16:42:54.817 -0.000 0.000 0.000