Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Thu Nov 15 06:21:05 PST 2018 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 55911 through 57091): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2018 JUL 01 00:01:10.000 2018 OCT 01 01:01:09.182 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_rec55922_55829_55922_r-v1.bsp spk_psp_rec56008_55920_56008_r-v1.bsp spk_psp_rec56100_56007_56100_r-v1.bsp spk_psp_rec56191_56098_56191_r-v1.bsp spk_psp_rec56280_56189_56280_r-v1.bsp spk_psp_rec56368_56278_56368_r-v1.bsp spk_psp_rec56459_56366_56459_r-v1.bsp spk_psp_rec56551_56457_56551_r-v1.bsp spk_psp_rec56638_56550_56638_r-v1.bsp spk_psp_rec56737_56636_56737_r-v1.bsp spk_psp_rec56820_56734_56820_r-v1.bsp spk_psp_rec56911_56817_56911_r-v1.bsp spk_psp_rec56997_56908_56997_r-v1.bsp spk_psp_rec57076_56995_57076_r-v1.bsp spk_psp_rec57180_57074_57180_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_psp48.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 55920 2018-07-01T18:55:50.815 0.000 0.000 -0.000 55935 2018-07-02T23:57:50.815 -0.001 0.000 -0.001 55950 2018-07-04T04:05:50.815 0.001 -0.000 0.001 55967 2018-07-05T11:52:50.816 0.001 0.000 0.001 55986 2018-07-06T23:24:50.816 0.001 -0.000 0.001 56007 2018-07-08T13:34:50.816 -0.001 0.000 0.001 56019 2018-07-09T13:02:50.816 -0.001 0.000 -0.001 56035 2018-07-10T19:01:50.816 0.000 0.000 0.000 56057 2018-07-12T12:09:50.816 -0.001 0.000 -0.001 56076 2018-07-13T23:41:50.816 -0.000 -0.000 -0.000 56089 2018-07-14T23:57:50.816 0.001 0.000 0.001 56098 2018-07-15T15:59:50.816 -0.002 0.000 0.002 56115 2018-07-17T00:28:50.816 0.001 -0.000 0.001 56134 2018-07-18T12:07:50.816 -0.001 0.000 -0.001 56153 2018-07-19T23:43:50.816 0.001 -0.000 0.001 56166 2018-07-20T23:57:50.816 -0.000 -0.000 -0.000 56177 2018-07-21T20:31:50.816 0.002 0.000 0.002 56189 2018-07-22T17:59:50.816 0.001 0.000 -0.001 56204 2018-07-23T23:00:50.816 0.001 -0.000 0.001 56225 2018-07-25T14:01:50.816 -0.001 0.000 -0.000 56243 2018-07-26T23:56:50.816 0.000 -0.000 0.000 56265 2018-07-28T17:04:50.816 -0.001 0.000 -0.001 56278 2018-07-29T16:19:50.816 -0.001 0.000 0.001 56290 2018-07-30T15:49:50.816 0.001 -0.000 0.000 56304 2018-07-31T17:59:50.816 0.001 -0.000 0.001 56313 2018-08-01T10:49:50.816 0.007 -0.000 0.005 56325 2018-08-02T09:15:50.816 -0.003 -0.000 -0.002 56340 2018-08-03T13:18:50.816 -0.003 0.000 -0.002 56356 2018-08-04T19:13:50.816 0.002 -0.000 0.001 56366 2018-08-05T12:40:50.816 -0.001 0.000 0.001 56381 2018-08-06T17:57:50.816 0.002 -0.000 0.001 56397 2018-08-07T23:51:50.816 -0.003 -0.000 -0.002 56403 2018-08-08T10:12:50.816 0.004 -0.000 -0.002 56419 2018-08-09T17:01:50.816 0.001 -0.000 0.000 56433 2018-08-10T19:12:50.816 0.001 -0.000 0.000 56446 2018-08-11T19:13:50.816 -0.003 0.000 -0.002 56457 2018-08-12T15:04:50.817 0.003 -0.000 -0.001 56472 2018-08-13T19:02:50.817 -0.002 -0.000 0.001 56484 2018-08-14T18:01:50.817 -0.000 0.000 -0.000 56499 2018-08-15T22:37:50.817 -0.003 -0.000 -0.001 56523 2018-08-17T18:47:50.817 0.000 0.000 0.000 56536 2018-08-18T18:42:50.817 -0.000 0.000 -0.000 56550 2018-08-19T20:59:50.817 -0.006 -0.000 0.002 56569 2018-08-21T09:22:50.817 0.001 0.000 0.000 56587 2018-08-22T18:22:50.817 0.004 0.000 -0.000 56600 2018-08-23T18:23:50.817 -0.003 -0.000 0.001 56616 2018-08-25T01:13:50.817 -0.005 0.000 -0.002 56628 2018-08-25T22:47:50.817 0.011 -0.000 -0.003 56636 2018-08-26T13:28:50.817 -0.005 0.000 0.002 56654 2018-08-28T00:28:50.817 0.001 -0.000 0.000 56667 2018-08-29T00:48:50.817 0.000 0.000 -0.000 56680 2018-08-29T23:57:50.817 -0.015 -0.000 0.004 56700 2018-08-31T14:27:50.817 0.003 0.000 0.000 56715 2018-09-01T17:42:50.817 0.001 -0.000 -0.000 56734 2018-09-03T05:39:50.817 -0.008 0.000 -0.002 56751 2018-09-04T13:31:50.817 -0.002 -0.000 -0.001 56762 2018-09-05T10:22:50.817 0.010 -0.000 0.001 56779 2018-09-06T17:22:50.817 -0.015 0.000 -0.000 56795 2018-09-07T23:57:50.817 0.006 0.000 0.001 56807 2018-09-08T22:21:50.817 -0.005 0.000 -0.001 56817 2018-09-09T15:44:50.817 0.016 0.000 -0.003 56834 2018-09-10T23:57:50.817 0.011 0.000 -0.002 56846 2018-09-11T23:23:50.817 -0.007 0.000 -0.001 56859 2018-09-12T23:35:50.817 -0.016 0.000 -0.003 56872 2018-09-13T23:53:50.817 0.010 -0.000 0.002 56885 2018-09-14T23:57:50.817 0.013 -0.000 0.003 56894 2018-09-15T16:38:50.817 0.012 -0.000 0.003 56908 2018-09-16T18:58:50.817 -0.010 0.000 -0.003 56928 2018-09-18T07:53:50.817 -0.014 -0.000 -0.000 56945 2018-09-19T16:23:50.817 0.017 -0.000 0.003 56958 2018-09-20T16:38:50.817 0.032 0.000 0.006 56975 2018-09-21T23:53:50.817 -0.001 -0.000 -0.000 56987 2018-09-22T22:45:50.817 -0.009 -0.000 -0.002 56995 2018-09-23T14:12:50.817 0.015 -0.000 -0.002 57009 2018-09-24T16:02:50.817 0.005 0.000 0.001 57021 2018-09-25T14:04:50.817 -0.002 -0.000 -0.000 57035 2018-09-26T15:36:50.817 -0.006 0.000 0.001 57048 2018-09-27T16:13:50.817 0.006 -0.000 0.000 57064 2018-09-28T22:52:50.817 -0.009 0.000 -0.001 57074 2018-09-29T17:05:50.817 0.008 -0.000 0.002