Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Thu Aug 1 08:57:57 PDT 2024 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 82877 through 84043): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2024 APR 01 00:01:10.000 2024 JUL 01 01:01:09.184 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_rec82965_82872_82965_r-v1.bsp spk_psp_rec83054_82960_83054_r-v1.bsp spk_psp_rec83144_83053_83144_r-v1.bsp spk_psp_rec83230_83143_83230_r-v1.bsp spk_psp_rec83324_83228_83324_r-v1.bsp spk_psp_rec83408_83323_83408_r-v1.bsp spk_psp_rec83501_83406_83501_r-v1.bsp spk_psp_rec83593_83499_83593_r-v1.bsp spk_psp_rec83680_83591_83680_r-v1.bsp spk_psp_rec83769_83678_83769_r-v1.bsp spk_psp_rec83862_83767_83862_r-v1.bsp spk_psp_rec83951_83860_83951_r-v1.bsp spk_psp_rec84042_83949_84042_r-v1.bsp spk_psp_rec84133_84040_84133_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_psp71.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 82888 2024-04-01T23:21:50.814 -0.001 -0.000 -0.001 82902 2024-04-03T01:33:50.814 0.001 -0.001 0.001 82920 2024-04-04T10:47:50.814 0.002 -0.000 0.001 82937 2024-04-05T18:26:50.814 -0.000 0.000 0.000 82951 2024-04-06T21:11:50.814 -0.000 -0.000 -0.001 82960 2024-04-07T13:18:50.814 0.001 -0.000 -0.001 82977 2024-04-08T21:48:50.814 -0.000 0.000 -0.001 82991 2024-04-09T23:57:50.814 0.001 0.000 0.002 83011 2024-04-11T12:47:50.814 -0.003 -0.000 0.002 83029 2024-04-12T23:04:50.814 0.000 0.000 0.001 83039 2024-04-13T17:46:50.814 -0.000 0.000 -0.001 83053 2024-04-14T19:08:50.814 -0.000 0.000 -0.000 83066 2024-04-15T20:15:50.814 0.001 0.000 0.003 83079 2024-04-16T20:35:50.814 -0.000 -0.000 -0.001 83093 2024-04-17T22:45:50.814 0.001 -0.000 0.001 83103 2024-04-18T17:27:50.814 0.000 -0.000 0.001 83119 2024-04-19T23:23:50.814 0.000 -0.000 0.000 83129 2024-04-20T18:05:50.814 -0.000 0.000 0.000 83143 2024-04-21T19:14:50.814 0.000 0.000 -0.001 83170 2024-04-23T21:57:50.814 0.000 -0.000 -0.001 83183 2024-04-24T22:17:50.814 -0.001 0.000 0.003 83196 2024-04-25T23:23:50.814 -0.000 0.000 -0.000 83209 2024-04-26T23:41:50.814 -0.000 -0.000 -0.001 83221 2024-04-27T21:25:50.814 -0.002 -0.000 0.004 83228 2024-04-28T10:11:50.814 -0.002 -0.000 0.004 83247 2024-04-29T22:20:50.814 0.000 0.000 0.000 83268 2024-05-01T13:58:50.814 -0.000 -0.000 -0.000 83281 2024-05-02T14:20:50.814 -0.001 0.000 -0.003 83298 2024-05-03T21:57:50.814 -0.000 0.000 -0.001 83311 2024-05-04T22:20:50.814 -0.000 0.000 -0.000 83323 2024-05-05T19:50:50.814 0.000 -0.000 -0.001 83337 2024-05-06T23:03:50.814 -0.001 -0.000 -0.002 83358 2024-05-08T14:19:50.814 0.001 -0.000 0.005 83375 2024-05-09T21:58:50.814 0.000 -0.000 0.001 83387 2024-05-10T20:33:50.814 0.001 -0.000 0.003 83406 2024-05-12T07:06:50.814 -0.001 -0.000 0.002 83426 2024-05-13T21:28:50.814 -0.003 -0.000 -0.012 83440 2024-05-14T23:39:50.814 0.003 -0.001 0.010 83452 2024-05-15T21:53:50.814 0.000 0.000 0.001 83472 2024-05-17T11:29:50.814 -0.000 0.000 -0.001 83487 2024-05-18T15:32:50.814 -0.000 0.000 -0.001 83499 2024-05-19T12:57:50.814 -0.000 -0.000 0.001 83512 2024-05-20T14:17:50.814 0.001 -0.000 0.002 83530 2024-05-21T23:53:50.814 0.000 -0.000 0.002 83541 2024-05-22T20:28:50.814 -0.000 0.000 -0.001 83569 2024-05-25T00:55:50.814 0.001 -0.000 0.003 83578 2024-05-25T17:44:50.814 -0.001 0.000 -0.003 83591 2024-05-26T17:01:50.814 0.001 -0.000 -0.003 83607 2024-05-27T23:34:50.815 -0.000 0.000 -0.000 83619 2024-05-28T21:54:50.815 0.000 0.000 0.000 83639 2024-05-30T11:51:50.815 -0.001 0.000 -0.006 83658 2024-05-31T23:23:50.815 -0.000 0.000 -0.002 83670 2024-06-01T21:14:50.815 0.000 0.000 0.000 83678 2024-06-02T11:48:50.815 0.000 -0.000 -0.002 83695 2024-06-03T20:33:50.815 -0.000 -0.000 -0.001 83709 2024-06-04T22:14:50.815 0.001 -0.000 -0.001 83720 2024-06-05T19:24:50.815 -0.001 0.000 -0.002 83733 2024-06-06T19:43:50.815 0.000 0.000 0.001 83751 2024-06-08T05:23:50.815 -0.000 -0.000 -0.001 83767 2024-06-09T10:18:50.815 0.001 0.000 -0.003 83786 2024-06-10T22:33:50.815 0.000 0.000 0.001 83799 2024-06-11T23:10:50.815 -0.001 -0.000 -0.005 83820 2024-06-13T14:27:50.815 -0.000 -0.000 -0.003 83838 2024-06-14T23:57:50.815 0.000 -0.000 -0.000 83849 2024-06-15T20:42:50.815 0.001 0.000 0.005 83860 2024-06-16T16:14:50.815 -0.000 0.000 0.003 83876 2024-06-17T22:23:50.815 0.001 -0.000 -0.004 83896 2024-06-19T12:37:50.815 -0.001 0.000 -0.004 83914 2024-06-20T21:29:50.815 0.000 -0.000 -0.002 83928 2024-06-21T23:57:50.815 0.000 0.000 -0.000 83940 2024-06-22T22:08:50.815 0.000 0.000 -0.001 83949 2024-06-23T14:42:50.815 0.000 0.000 -0.002 83965 2024-06-24T21:40:50.815 -0.000 -0.000 -0.003 83978 2024-06-25T21:23:50.815 0.001 0.000 -0.002 83991 2024-06-26T22:18:50.815 -0.000 0.000 -0.004 84003 2024-06-27T20:45:50.815 -0.000 -0.000 -0.004 84016 2024-06-28T21:04:50.815 0.000 0.000 -0.000 84029 2024-06-29T21:23:50.815 0.000 -0.000 0.004 84040 2024-06-30T17:45:50.815 0.000 -0.000 0.004