Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Sat Nov 4 08:30:15 PDT 2023 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 79347 through 80527): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2023 JUL 01 00:01:10.000 2023 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_rec79370_79281_79370_r-v1.bsp spk_psp_rec79458_79367_79458_r-v1.bsp spk_psp_rec79539_79457_79539_r-v1.bsp spk_psp_rec79640_79537_79640_r-v1.bsp spk_psp_rec79728_79637_79728_r-v1.bsp spk_psp_rec79818_79727_79818_r-v1.bsp spk_psp_rec79910_79816_79910_r-v1.bsp spk_psp_rec79996_79908_79996_r-v1.bsp spk_psp_rec80087_79994_80087_r-v1.bsp spk_psp_rec80175_80085_80175_r-v1.bsp spk_psp_rec80267_80173_80267_r-v1.bsp spk_psp_rec80360_80265_80360_r-v1.bsp spk_psp_rec80449_80360_80449_r-v1.bsp spk_psp_rec80532_80447_80532_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_psp68.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 79359 2023-07-01T22:42:50.815 0.014 0.000 0.006 79367 2023-07-02T14:13:50.815 -0.014 0.000 0.006 79384 2023-07-03T21:27:50.815 -0.004 -0.000 -0.002 79396 2023-07-04T20:55:50.815 -0.007 0.000 0.002 79410 2023-07-05T23:45:50.816 0.002 -0.000 0.001 79424 2023-07-07T01:25:50.816 0.001 -0.000 -0.000 79435 2023-07-07T20:49:50.816 -0.008 -0.000 -0.004 79444 2023-07-08T14:51:50.816 0.002 0.000 -0.000 79457 2023-07-09T14:44:50.816 -0.003 0.000 0.002 79473 2023-07-10T20:47:50.816 0.002 -0.000 -0.001 79486 2023-07-11T20:11:50.816 0.002 -0.000 0.001 79499 2023-07-12T20:29:50.816 0.003 0.000 0.001 79514 2023-07-14T02:15:50.816 -0.006 -0.000 -0.003 79524 2023-07-14T19:14:50.816 -0.014 -0.000 -0.007 79537 2023-07-15T20:59:50.816 0.006 -0.000 0.002 79553 2023-07-17T01:28:50.816 -0.017 -0.000 -0.008 79575 2023-07-18T20:14:50.816 0.004 0.000 0.002 79589 2023-07-19T21:43:50.816 -0.008 0.000 0.004 79603 2023-07-20T22:57:50.816 0.021 0.000 0.011 79614 2023-07-21T19:31:50.816 -0.017 -0.000 -0.009 79628 2023-07-22T22:59:50.816 0.013 -0.000 0.001 79637 2023-07-23T15:08:50.816 -0.008 -0.000 0.004 79653 2023-07-24T21:44:50.816 0.027 -0.000 0.001 79665 2023-07-25T20:04:50.816 -0.015 0.000 0.002 79680 2023-07-26T22:56:50.816 -0.002 -0.000 -0.001 79692 2023-07-27T23:14:50.816 0.003 0.000 0.001 79706 2023-07-28T23:33:50.816 -0.001 -0.000 -0.001 79716 2023-07-29T19:53:50.816 0.009 0.000 0.005 79727 2023-07-30T15:40:50.816 0.003 -0.000 -0.002 79743 2023-07-31T22:09:50.816 -0.004 -0.000 -0.001 79755 2023-08-01T21:02:50.816 0.007 0.000 0.004 79771 2023-08-03T02:57:50.816 -0.000 -0.000 -0.000 79787 2023-08-04T08:44:50.816 0.023 0.000 0.014 79802 2023-08-05T12:55:50.816 -0.023 -0.000 -0.013 79816 2023-08-06T14:30:50.816 0.005 -0.000 0.000 79830 2023-08-07T17:16:50.816 0.002 -0.000 0.001 79842 2023-08-08T15:42:50.816 0.000 -0.000 0.000 79855 2023-08-09T15:58:50.816 -0.009 -0.000 -0.006 79872 2023-08-10T23:48:50.816 0.003 -0.000 0.002 79885 2023-08-11T23:57:50.816 0.013 -0.000 0.008 79895 2023-08-12T18:48:50.816 -0.001 -0.000 -0.001 79908 2023-08-13T17:53:50.817 -0.012 0.000 0.006 79923 2023-08-14T23:09:50.817 0.000 0.000 0.000 79934 2023-08-15T19:43:50.817 -0.009 -0.000 -0.006 79945 2023-08-16T16:18:50.817 0.005 -0.000 0.003 79955 2023-08-17T10:59:50.817 0.001 0.000 0.001 79972 2023-08-18T18:46:50.817 0.001 0.000 0.001 79986 2023-08-19T20:58:50.817 0.007 0.000 0.004 79994 2023-08-20T10:43:50.817 0.005 -0.000 -0.003 80020 2023-08-22T12:28:50.817 0.003 -0.000 0.002 80036 2023-08-23T18:08:50.817 0.010 -0.000 0.005 80051 2023-08-24T22:08:50.817 -0.003 -0.000 -0.002 80064 2023-08-25T22:47:50.817 -0.009 -0.000 -0.006 80077 2023-08-26T23:06:50.817 -0.001 -0.000 -0.000 80085 2023-08-27T12:51:50.817 0.001 0.000 -0.001 80100 2023-08-28T18:06:50.817 0.001 0.000 0.000 80116 2023-08-29T23:57:50.817 -0.003 0.000 -0.002 80130 2023-08-31T02:05:50.817 -0.005 -0.000 -0.003 80149 2023-09-01T13:43:50.817 0.000 0.000 0.000 80163 2023-09-02T15:52:50.817 -0.010 0.000 -0.006 80173 2023-09-03T09:23:50.817 0.009 0.000 -0.005 80190 2023-09-04T18:18:50.817 0.002 -0.000 0.002 80203 2023-09-05T18:18:50.817 -0.011 0.000 -0.005 80224 2023-09-07T09:55:50.817 0.011 0.000 0.007 80242 2023-09-08T19:36:50.817 0.001 -0.000 0.000 80254 2023-09-09T17:53:50.817 0.000 -0.000 0.000 80265 2023-09-10T13:24:50.817 -0.007 -0.000 0.004 80283 2023-09-11T23:57:50.817 0.002 0.000 0.001 80300 2023-09-13T08:01:50.817 -0.004 0.000 -0.002 80317 2023-09-14T15:49:50.817 -0.000 0.000 0.000 80335 2023-09-16T00:50:50.817 -0.005 -0.000 0.001 80347 2023-09-16T23:54:50.817 0.003 0.000 0.002 80360 2023-09-17T23:01:50.817 -0.005 0.001 0.003 80385 2023-09-19T22:57:50.817 -0.002 0.000 -0.001 80398 2023-09-20T22:08:50.817 0.005 0.000 -0.004 80412 2023-09-22T01:26:50.817 -0.007 -0.000 -0.004 80432 2023-09-23T14:50:50.817 0.004 0.000 0.003 80447 2023-09-24T17:41:50.817 -0.002 -0.000 0.001 80460 2023-09-25T18:45:50.817 0.001 -0.000 0.000 80476 2023-09-27T01:04:50.817 -0.000 0.000 -0.000 80488 2023-09-27T23:32:50.817 0.002 0.000 0.001 80509 2023-09-29T14:48:50.817 0.001 -0.000 0.000 80521 2023-09-30T13:16:50.817 -0.002 0.000 -0.001