Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Tue Feb 2 16:49:20 PST 2016 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 43026 through 44205): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2015 OCT 01 00:01:09.000 2016 JAN 01 01:01:08.183 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_rec43055_42963_43055_r-v1.bsp spk_psp_rec43149_43048_43149_r-v1.bsp spk_psp_rec43237_43148_43237_r-v1.bsp spk_psp_rec43338_43230_43338_r-v1.bsp spk_psp_rec43406_43331_43406_r-v1.bsp spk_psp_rec43509_43401_43509_r-v1.bsp spk_psp_rec43599_43506_43599_r-v1.bsp spk_psp_rec43693_43594_43693_r-v1.bsp spk_psp_rec43780_43689_43780_r-v1.bsp spk_psp_rec43868_43774_43868_r-v1.bsp spk_psp_rec43956_43863_43956_r-v1.bsp spk_psp_rec44060_43952_44060_r-v1.bsp spk_psp_rec44126_44058_44126_r-v1.bsp spk_psp_rec44208_44122_44208_r-v1.bsp spk_psp_rec44316_44203_44316_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_psp37.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 43030 2015-10-01T10:35:51.817 0.001 -0.000 0.002 43048 2015-10-02T19:11:19.817 -0.001 0.000 0.002 43073 2015-10-04T19:03:01.847 -0.000 0.000 -0.001 43088 2015-10-05T23:05:10.927 0.000 0.000 0.000 43101 2015-10-06T23:24:33.647 -0.000 -0.000 -0.001 43113 2015-10-07T21:52:21.817 0.000 0.000 0.001 43122 2015-10-08T14:40:47.087 -0.000 0.000 -0.000 43148 2015-10-10T14:40:11.817 -0.000 0.000 0.000 43162 2015-10-11T16:44:42.717 -0.001 -0.000 0.001 43178 2015-10-12T23:23:53.377 0.000 0.000 0.001 43189 2015-10-13T19:58:42.867 -0.000 -0.000 -0.001 43202 2015-10-14T20:16:49.827 -0.000 -0.000 -0.000 43216 2015-10-15T22:27:40.057 0.000 -0.000 0.000 43230 2015-10-16T23:32:18.817 0.000 0.000 -0.000 43254 2015-10-18T21:31:27.027 -0.000 0.000 -0.000 43267 2015-10-19T21:50:09.147 -0.000 -0.000 -0.001 43279 2015-10-20T20:16:27.067 -0.000 0.000 -0.000 43299 2015-10-22T09:40:18.977 0.000 0.000 0.001 43320 2015-10-24T00:06:51.817 -0.000 0.000 0.000 43331 2015-10-24T20:24:36.817 0.000 0.000 -0.001 43357 2015-10-26T22:07:53.647 0.000 0.000 0.001 43370 2015-10-27T22:26:22.017 0.000 -0.000 0.000 43382 2015-10-28T20:52:47.157 0.000 0.000 -0.000 43401 2015-10-30T07:18:32.817 -0.000 -0.000 0.001 43431 2015-11-01T15:51:47.137 0.001 -0.000 -0.001 43452 2015-11-03T07:27:11.127 0.001 0.000 0.002 43471 2015-11-04T19:21:31.817 0.001 -0.000 0.002 43486 2015-11-05T23:21:09.427 -0.001 -0.000 -0.005 43500 2015-11-07T01:28:51.817 0.001 0.000 0.003 43506 2015-11-07T11:49:00.817 -0.001 -0.000 0.003 43523 2015-11-08T19:52:51.817 0.000 -0.000 -0.000 43537 2015-11-09T22:42:43.997 -0.000 0.000 -0.001 43545 2015-11-10T13:40:17.327 0.000 0.000 0.002 43560 2015-11-11T17:43:07.717 -0.000 -0.000 -0.000 43575 2015-11-12T21:45:55.147 -0.000 0.000 -0.001 43594 2015-11-14T08:12:27.817 0.000 0.000 -0.000 43611 2015-11-15T17:05:21.817 0.000 0.000 0.001 43627 2015-11-16T23:00:51.807 0.000 0.000 0.000 43640 2015-11-17T23:19:25.787 -0.000 -0.000 -0.000 43651 2015-11-18T19:53:32.177 0.000 0.000 0.000 43667 2015-11-20T01:48:51.817 0.000 -0.000 0.000 43689 2015-11-21T18:00:41.817 -0.000 0.000 0.001 43704 2015-11-22T22:59:48.777 -0.000 -0.000 -0.000 43716 2015-11-23T21:25:56.597 -0.000 0.000 -0.000 43726 2015-11-24T16:07:50.787 0.000 0.000 0.001 43737 2015-11-25T12:41:54.327 -0.000 0.000 -0.002 43756 2015-11-26T23:48:51.817 0.000 -0.000 0.001 43774 2015-11-28T08:47:18.816 0.000 -0.000 -0.002 43792 2015-11-29T19:31:56.256 -0.000 -0.000 -0.001 43804 2015-11-30T17:58:19.236 0.001 -0.000 0.003 43814 2015-12-01T12:40:13.556 0.000 0.000 0.000 43829 2015-12-02T16:24:27.526 0.000 -0.000 0.001 43843 2015-12-03T18:53:51.286 0.000 0.000 0.000 43863 2015-12-05T07:17:24.816 -0.000 -0.000 0.000 43894 2015-12-07T18:15:19.692 -0.000 -0.000 -0.000 43906 2015-12-08T16:03:07.720 -0.000 -0.000 0.000 43918 2015-12-09T14:44:28.931 0.000 -0.000 0.000 43931 2015-12-10T14:42:45.816 0.000 -0.000 -0.000 43952 2015-12-12T05:37:05.816 -0.000 0.000 0.000 43973 2015-12-13T21:58:42.335 -0.000 0.000 -0.000 43984 2015-12-14T18:32:45.246 -0.000 -0.000 -0.001 43998 2015-12-15T20:42:36.816 0.000 0.000 0.002 44010 2015-12-16T19:09:36.816 -0.000 -0.000 -0.002 44033 2015-12-18T13:33:51.816 0.000 0.000 -0.000 44058 2015-12-20T11:48:51.816 -0.000 0.000 0.000 44071 2015-12-21T13:11:21.816 -0.000 -0.000 -0.001 44088 2015-12-22T20:58:51.816 0.000 0.000 0.000 44107 2015-12-24T08:33:51.816 0.000 -0.000 0.001 44122 2015-12-25T11:29:10.816 -0.000 0.000 0.001 44152 2015-12-27T20:40:22.619 -0.000 -0.000 -0.002 44166 2015-12-28T22:50:52.860 0.000 -0.000 0.000 44177 2015-12-29T19:24:58.992 0.000 0.000 0.002 44183 2015-12-30T06:37:17.247 -0.000 0.000 -0.003 44203 2015-12-31T18:57:00.816 0.000 0.000 -0.002