Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Thu Aug 8 09:04:15 PDT 2019 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 59427 through 60594): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2019 APR 01 00:01:10.000 2019 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_rec59509_59424_59509_r-v1.bsp spk_psp_rec59597_59507_59597_r-v1.bsp spk_psp_rec59695_59595_59695_r-v1.bsp spk_psp_rec59773_59693_59773_r-v1.bsp spk_psp_rec59875_59770_59875_r-v1.bsp spk_psp_rec59965_59873_59965_r-v1.bsp spk_psp_rec60053_59964_60053_r-v1.bsp spk_psp_rec60136_60051_60136_r-v1.bsp spk_psp_rec60234_60134_60234_r-v1.bsp spk_psp_rec60322_60232_60322_r-v1.bsp spk_psp_rec60413_60320_60413_r-v1.bsp spk_psp_rec60504_60410_60504_r-v1.bsp spk_psp_rec60594_60502_60594_r-v1.bsp spk_psp_rec60681_60593_60681_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_psp51.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 59439 2019-04-01T23:57:50.814 0.001 0.000 0.000 59451 2019-04-02T21:32:50.814 -0.003 0.000 0.001 59463 2019-04-03T21:01:50.814 0.002 0.000 0.001 59476 2019-04-04T21:20:50.814 -0.002 -0.000 -0.001 59490 2019-04-05T23:31:50.814 0.002 -0.000 0.001 59507 2019-04-07T06:02:50.814 -0.002 -0.000 0.001 59520 2019-04-08T07:37:50.814 0.001 0.000 0.000 59537 2019-04-09T15:02:50.814 -0.000 -0.000 -0.000 59553 2019-04-10T21:01:50.814 -0.000 -0.000 -0.000 59569 2019-04-12T03:16:50.814 -0.002 0.000 -0.001 59586 2019-04-13T11:04:50.814 0.000 0.000 0.000 59595 2019-04-14T02:38:50.814 -0.001 -0.000 0.001 59613 2019-04-15T13:07:50.814 -0.002 0.000 -0.001 59630 2019-04-16T21:21:50.814 -0.002 -0.000 -0.001 59642 2019-04-17T19:48:50.814 0.002 0.000 0.001 59657 2019-04-18T23:51:50.814 -0.002 -0.000 -0.001 59670 2019-04-19T23:57:50.814 0.001 -0.000 0.000 59683 2019-04-20T23:57:50.814 -0.002 0.000 -0.000 59693 2019-04-21T17:56:50.814 0.000 -0.000 -0.000 59709 2019-04-23T01:06:50.814 -0.000 -0.000 -0.000 59725 2019-04-24T07:02:50.814 -0.001 -0.000 -0.000 59747 2019-04-25T23:57:50.814 -0.001 0.000 -0.001 59759 2019-04-26T22:37:50.814 0.001 -0.000 0.001 59770 2019-04-27T18:24:50.814 -0.000 0.000 0.000 59786 2019-04-29T01:07:50.814 -0.002 -0.000 -0.001 59801 2019-04-30T05:10:50.814 0.001 -0.000 0.001 59819 2019-05-01T14:50:50.814 0.000 -0.000 0.000 59832 2019-05-02T15:09:50.814 -0.002 0.000 -0.001 59849 2019-05-03T22:56:50.814 -0.001 0.000 -0.000 59861 2019-05-04T21:00:50.814 0.001 0.000 0.000 59873 2019-05-05T18:35:50.814 -0.001 -0.000 0.001 59889 2019-05-07T01:45:50.814 -0.001 -0.000 -0.001 59898 2019-05-07T18:25:50.814 0.002 0.000 0.001 59920 2019-05-09T11:44:50.814 0.001 0.000 0.000 59938 2019-05-10T21:00:50.814 -0.003 0.000 -0.001 59951 2019-05-11T21:42:50.814 0.000 -0.000 0.000 59964 2019-05-12T20:47:50.814 0.002 0.000 -0.001 59977 2019-05-13T22:20:50.814 0.000 -0.000 0.000 59991 2019-05-14T23:57:50.814 0.002 0.000 0.000 60002 2019-05-15T20:49:50.814 0.001 0.000 0.001 60017 2019-05-16T23:57:50.814 0.001 0.000 -0.000 60027 2019-05-17T19:50:50.814 0.000 0.000 0.000 60038 2019-05-18T16:18:50.814 -0.002 -0.000 -0.001 60051 2019-05-19T15:30:50.814 -0.000 -0.000 0.000 60069 2019-05-21T02:03:50.814 -0.001 0.000 -0.001 60084 2019-05-22T06:26:50.814 0.003 0.000 0.002 60101 2019-05-23T14:14:50.814 -0.005 0.000 -0.003 60119 2019-05-24T23:54:50.814 0.001 -0.000 0.001 60134 2019-05-26T03:20:50.814 0.001 -0.000 -0.000 60152 2019-05-27T13:37:50.814 -0.003 -0.000 -0.002 60168 2019-05-28T19:34:50.815 0.000 0.000 0.000 60187 2019-05-30T07:04:50.815 0.001 0.000 0.001 60209 2019-05-31T23:50:50.815 -0.001 -0.000 -0.000 60222 2019-06-01T23:57:50.815 -0.000 -0.000 -0.000 60232 2019-06-02T18:02:50.815 -0.001 -0.000 0.001 60253 2019-06-04T10:30:50.815 -0.001 -0.000 -0.001 60271 2019-06-05T20:09:50.815 0.002 -0.000 0.001 60288 2019-06-07T03:57:50.815 -0.001 -0.000 -0.000 60305 2019-06-08T11:45:50.815 0.001 0.000 0.000 60320 2019-06-09T14:36:50.815 -0.000 -0.000 0.000 60332 2019-06-10T14:14:50.815 -0.002 -0.000 -0.001 60347 2019-06-11T18:17:50.815 0.003 -0.000 0.002 60360 2019-06-12T18:04:50.815 -0.002 0.000 -0.000 60376 2019-06-13T23:57:50.815 -0.002 -0.000 -0.000 60387 2019-06-14T20:14:50.815 0.000 0.000 -0.000 60399 2019-06-15T19:32:50.815 -0.001 0.000 -0.001 60410 2019-06-16T15:51:50.815 0.004 0.000 0.003 60426 2019-06-17T22:02:50.815 0.003 0.000 0.002 60438 2019-06-18T20:28:50.815 -0.002 0.000 -0.001 60460 2019-06-20T13:37:50.815 -0.003 0.000 -0.002 60478 2019-06-21T23:16:50.815 0.002 -0.000 0.001 60490 2019-06-22T21:13:50.815 0.001 -0.000 0.000 60502 2019-06-23T18:59:50.815 0.000 -0.000 -0.000 60520 2019-06-25T05:49:50.815 0.002 0.000 0.002 60543 2019-06-26T23:57:50.815 0.001 -0.000 -0.001 60555 2019-06-27T23:16:50.815 -0.000 -0.000 -0.000 60568 2019-06-28T23:34:50.815 -0.002 0.000 -0.001 60580 2019-06-29T22:01:50.815 -0.001 0.000 -0.001 60593 2019-06-30T21:10:50.815 -0.000 0.000 0.000