Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Tue Aug 2 11:59:46 PDT 2022 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 73495 through 74662): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2022 APR 01 00:01:10.000 2022 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_rec73619_73529_73619_r-v1.bsp spk_psp_rec73708_73618_73708_r-v1.bsp spk_psp_rec73799_73706_73799_r-v1.bsp spk_psp_rec73889_73797_73889_r-v1.bsp spk_psp_rec73981_73887_73981_r-v1.bsp spk_psp_rec74064_73979_74064_r-v1.bsp spk_psp_rec74157_74062_74157_r-v1.bsp spk_psp_rec74246_74155_74246_r-v1.bsp spk_psp_rec74338_74245_74338_r-v1.bsp spk_psp_rec74426_74336_74426_r-v1.bsp spk_psp_rec74518_74424_74518_r-v1.bsp spk_psp_rec74605_74516_74605_r-v1.bsp spk_psp_rec74700_74603_74700_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_psp63.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 73506 2022-04-01T22:44:50.814 -0.000 0.000 -0.000 73517 2022-04-02T19:24:50.814 0.000 -0.000 0.001 73529 2022-04-03T17:40:50.814 -0.000 0.000 -0.000 73540 2022-04-04T14:25:50.814 -0.001 0.000 -0.002 73563 2022-04-06T09:19:50.814 -0.001 -0.000 -0.003 73576 2022-04-07T09:43:50.814 0.001 0.000 0.002 73595 2022-04-08T20:34:50.814 -0.000 -0.000 0.000 73618 2022-04-10T15:20:50.814 -0.000 0.000 -0.000 73635 2022-04-11T23:57:50.814 -0.000 0.000 -0.001 73653 2022-04-13T09:34:50.814 -0.000 0.000 -0.001 73667 2022-04-14T11:53:50.814 0.000 0.000 0.001 73679 2022-04-15T10:19:50.814 0.000 0.000 0.001 73694 2022-04-16T14:22:50.814 -0.001 -0.000 -0.003 73706 2022-04-17T11:46:50.814 0.001 0.000 -0.003 73716 2022-04-18T07:30:50.814 0.002 0.000 0.005 73732 2022-04-19T13:25:50.814 -0.002 0.000 -0.004 73763 2022-04-21T23:23:50.814 -0.000 0.000 -0.000 73774 2022-04-22T19:57:50.814 0.001 -0.000 0.004 73785 2022-04-23T16:15:50.814 0.000 -0.000 0.000 73797 2022-04-24T14:24:50.814 -0.000 0.000 0.000 73813 2022-04-25T20:52:50.814 0.000 0.000 0.001 73825 2022-04-26T19:19:50.814 -0.002 0.000 -0.005 73835 2022-04-27T14:00:50.814 0.001 0.000 0.004 73852 2022-04-28T21:30:50.814 -0.001 0.000 -0.003 73873 2022-04-30T12:55:50.814 -0.001 -0.000 -0.002 73887 2022-05-01T14:12:50.814 0.001 0.000 -0.002 73899 2022-05-02T13:40:50.814 0.000 -0.000 0.001 73916 2022-05-03T21:27:50.814 0.000 0.000 0.002 73935 2022-05-05T08:57:50.814 -0.000 0.000 -0.001 73953 2022-05-06T18:38:50.814 0.000 -0.000 0.001 73969 2022-05-07T23:57:50.814 0.001 0.000 -0.001 73979 2022-05-08T18:13:50.814 -0.000 -0.000 0.000 74003 2022-05-10T16:07:50.814 0.000 0.000 0.000 74018 2022-05-11T20:10:50.814 0.000 0.000 0.001 74032 2022-05-12T21:31:50.814 -0.000 0.000 0.000 74045 2022-05-13T22:40:50.814 -0.001 0.000 -0.002 74062 2022-05-15T05:26:50.814 0.000 0.000 -0.001 74078 2022-05-16T12:23:50.814 -0.000 -0.000 0.000 74092 2022-05-17T14:35:50.814 0.001 -0.000 0.007 74104 2022-05-18T12:36:50.814 -0.000 -0.000 0.001 74118 2022-05-19T14:31:50.814 0.000 -0.000 -0.000 74134 2022-05-20T20:31:50.814 -0.001 -0.000 0.001 74144 2022-05-21T15:06:50.814 0.000 -0.000 -0.001 74155 2022-05-22T11:22:50.814 0.000 0.000 -0.002 74172 2022-05-23T19:51:50.814 0.001 0.000 0.001 74184 2022-05-24T18:39:50.814 -0.000 0.000 -0.002 74197 2022-05-25T18:57:50.814 -0.000 0.000 -0.002 74216 2022-05-27T06:30:50.814 0.000 0.000 0.004 74236 2022-05-28T19:56:50.815 -0.001 0.000 -0.008 74245 2022-05-29T11:42:50.815 0.000 0.000 -0.001 74262 2022-05-30T20:31:50.815 0.000 -0.000 0.000 74284 2022-06-01T13:40:50.815 0.000 -0.000 0.002 74294 2022-06-02T08:22:50.815 -0.000 0.000 -0.001 74311 2022-06-03T16:10:50.815 0.000 0.000 0.001 74327 2022-06-04T22:05:50.815 -0.001 -0.000 -0.008 74336 2022-06-05T13:54:50.815 0.001 0.000 -0.006 74347 2022-06-06T11:30:50.815 0.000 0.000 0.001 74370 2022-06-08T05:49:50.815 -0.000 0.000 0.001 74388 2022-06-09T15:46:50.815 0.000 0.000 0.001 74403 2022-06-10T19:58:50.815 0.000 -0.000 0.003 74418 2022-06-11T23:57:50.815 -0.001 -0.000 -0.002 74424 2022-06-12T11:17:50.815 0.000 0.000 0.000 74444 2022-06-14T00:28:50.815 -0.000 -0.000 -0.000 74465 2022-06-15T15:42:50.815 0.000 -0.000 0.000 74479 2022-06-16T18:21:50.815 0.000 -0.000 0.001 74494 2022-06-17T22:24:50.815 -0.000 0.000 -0.004 74506 2022-06-18T20:23:50.815 0.000 -0.000 0.000 74516 2022-06-19T14:42:50.815 -0.000 0.000 0.007 74525 2022-06-20T08:22:50.815 -0.001 -0.000 -0.016 74548 2022-06-22T03:23:50.815 0.000 -0.000 0.007 74566 2022-06-23T13:03:50.815 -0.000 -0.000 -0.002 74579 2022-06-24T13:23:50.815 0.000 0.000 0.004 74596 2022-06-25T20:48:50.815 -0.000 0.000 -0.002 74603 2022-06-26T09:46:50.815 0.000 0.000 0.000 74626 2022-06-28T05:18:50.815 -0.000 -0.000 -0.006 74640 2022-06-29T07:29:50.815 0.000 -0.000 0.012 74657 2022-06-30T15:17:50.815 0.000 -0.000 -0.001