Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Wed Feb 25 17:59:55 PST 2015 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 38341 through 39521): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2014 OCT 01 00:01:07.182 2015 JAN 01 01:01:07.183 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_rec38391_38288_38391_r-v1.bsp spk_psp_rec38430_38388_38430_r-v1.bsp spk_psp_rec38478_38429_38478_r-v1.bsp spk_psp_rec38561_38473_38561_r-v1.bsp spk_psp_rec38656_38548_38656_r-v1.bsp spk_psp_rec38751_38636_38751_r-v1.bsp spk_psp_rec38837_38735_38837_r-v1.bsp spk_psp_rec38928_38817_38928_r-v1.bsp spk_psp_rec39017_38916_39017_r-v1.bsp spk_psp_rec39097_38999_39097_r-v1.bsp spk_psp_rec39197_39085_39197_r-v1.bsp spk_psp_rec39287_39180_39287_r-v1.bsp spk_psp_rec39360_39270_39360_r-v1.bsp spk_psp_rec39451_39345_39451_r-v1.bsp spk_psp_rec39531_39438_39531_r-v1.bsp spk_psp_rec39631_39514_39631_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_psp33.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 38351 2014-10-01T19:33:52.817 -0.015 0.000 -0.002 38371 2014-10-03T09:01:52.817 0.007 -0.000 0.001 38388 2014-10-04T17:13:52.817 -0.012 0.000 0.001 38409 2014-10-06T08:07:52.817 0.044 0.000 0.003 38424 2014-10-07T12:02:52.817 0.030 0.000 0.003 38429 2014-10-07T21:18:52.817 -0.036 -0.000 -0.004 38449 2014-10-09T10:56:52.817 0.009 0.001 0.000 38466 2014-10-10T18:41:52.817 0.017 -0.000 0.001 38473 2014-10-11T08:24:52.817 -0.041 0.001 0.004 38488 2014-10-12T11:53:52.817 0.038 -0.000 0.001 38509 2014-10-14T02:57:52.817 0.023 -0.000 0.001 38530 2014-10-15T18:19:52.817 0.005 0.000 0.000 38543 2014-10-16T19:09:52.817 0.002 -0.000 -0.000 38548 2014-10-17T05:12:27.817 0.014 -0.000 0.001 38584 2014-10-19T23:58:50.817 -0.033 -0.000 0.001 38597 2014-10-20T23:45:52.817 -0.023 0.000 0.001 38610 2014-10-21T23:58:50.817 0.010 0.000 -0.000 38620 2014-10-22T19:23:40.817 -0.005 0.001 0.000 38635 2014-10-23T22:30:36.817 0.029 0.001 0.000 38636 2014-10-24T01:18:01.817 0.012 0.000 -0.000 38669 2014-10-26T15:13:20.817 -0.019 0.001 -0.000 38686 2014-10-27T22:56:39.817 -0.033 0.001 -0.001 38699 2014-10-28T23:13:30.817 -0.025 0.000 -0.001 38725 2014-10-30T23:46:53.817 0.001 0.000 -0.000 38731 2014-10-31T10:59:33.817 -0.011 -0.000 -0.000 38735 2014-10-31T17:50:45.817 -0.012 -0.000 0.000 38761 2014-11-02T18:46:52.817 0.004 -0.000 0.000 38773 2014-11-03T17:02:05.817 -0.001 0.001 0.000 38784 2014-11-04T13:56:52.817 0.009 -0.000 0.001 38799 2014-11-05T17:57:42.817 0.002 0.000 0.000 38816 2014-11-07T01:43:57.817 0.012 -0.001 0.001 38817 2014-11-07T02:58:04.817 0.049 0.002 -0.000 38851 2014-11-09T19:04:10.817 -0.013 0.000 -0.001 38859 2014-11-10T10:01:45.817 0.033 0.000 0.003 38873 2014-11-11T11:50:54.817 -0.018 0.000 -0.001 38889 2014-11-12T18:30:52.817 -0.003 -0.000 -0.000 38894 2014-11-13T03:47:44.817 -0.026 -0.000 -0.000 38907 2014-11-14T04:14:29.817 -0.026 0.000 0.001 38916 2014-11-14T20:29:54.817 0.012 -0.000 0.001 38943 2014-11-16T23:33:06.817 0.011 0.000 -0.001 38967 2014-11-18T19:04:32.817 0.003 0.000 -0.000 38981 2014-11-19T22:33:37.817 0.015 -0.000 -0.001 38990 2014-11-20T15:03:25.817 -0.004 -0.000 -0.000 38999 2014-11-21T06:42:30.817 0.013 0.000 -0.002 39032 2014-11-23T21:56:55.817 -0.001 -0.000 0.000 39041 2014-11-24T14:46:38.817 -0.021 -0.001 0.002 39058 2014-11-25T22:34:33.817 0.006 -0.000 -0.001 39069 2014-11-26T18:50:52.817 -0.001 -0.000 -0.000 39084 2014-11-27T21:42:52.816 -0.019 -0.000 0.004 39085 2014-11-28T01:11:52.816 0.005 0.000 -0.001 39108 2014-11-29T18:51:52.816 0.006 0.000 -0.001 39121 2014-11-30T18:53:52.816 0.010 0.000 -0.002 39142 2014-12-02T11:14:52.816 -0.000 -0.000 -0.000 39158 2014-12-03T16:28:52.816 0.006 0.000 -0.000 39171 2014-12-04T17:10:52.816 -0.006 -0.000 -0.001 39180 2014-12-05T09:09:47.816 0.007 0.000 -0.002 39210 2014-12-07T18:47:22.816 -0.006 0.000 0.000 39222 2014-12-08T16:29:48.816 -0.004 0.000 -0.001 39232 2014-12-09T11:19:09.816 0.001 0.000 0.000 39248 2014-12-10T17:51:44.816 -0.007 -0.000 0.000 39262 2014-12-11T18:51:52.816 -0.007 -0.000 0.001 39270 2014-12-12T09:29:44.816 0.005 -0.000 -0.001 39299 2014-12-14T16:33:14.816 0.014 -0.000 0.004 39313 2014-12-15T18:28:52.816 0.001 -0.000 0.000 39324 2014-12-16T14:38:41.816 -0.005 -0.000 0.002 39339 2014-12-17T19:09:45.816 -0.001 0.000 -0.000 39345 2014-12-18T06:13:52.816 0.013 -0.000 -0.000 39377 2014-12-20T18:50:52.816 -0.007 -0.000 -0.002 39392 2014-12-21T23:09:53.816 -0.001 -0.000 0.000 39402 2014-12-22T17:00:44.816 -0.003 -0.000 -0.001 39415 2014-12-23T17:15:54.816 0.005 -0.000 0.001 39424 2014-12-24T10:44:52.816 -0.010 -0.000 -0.002 39438 2014-12-25T13:16:52.816 0.007 -0.000 -0.001 39465 2014-12-27T15:25:52.816 0.006 0.000 0.001 39474 2014-12-28T08:31:52.816 0.008 0.000 -0.001 39488 2014-12-29T10:42:52.816 -0.003 0.000 0.000 39505 2014-12-30T18:13:52.816 -0.001 -0.000 -0.000 39514 2014-12-31T09:46:49.816 0.000 -0.000 -0.000