Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Tue Jul 29 11:19:58 PDT 2014 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 35992 through 37159): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2014 APR 01 00:01:07.185 2014 JUL 01 01:01:07.184 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_rec36068_35975_36068_r-v1.bsp spk_psp_rec36157_36064_36157_r-v1.bsp spk_psp_rec36247_36156_36247_r-v1.bsp spk_psp_rec36337_36246_36337_r-v1.bsp spk_psp_rec36415_36336_36415_r-v1.bsp spk_psp_rec36503_36414_36503_r-v1.bsp spk_psp_rec36607_36501_36607_r-v1.bsp spk_psp_rec36697_36605_36697_r-v1.bsp spk_psp_rec36769_36695_36769_r-v1.bsp spk_psp_rec36876_36767_36876_r-v1.bsp spk_psp_rec36960_36874_36960_r-v1.bsp spk_psp_rec37055_36959_37055_r-v1.bsp spk_psp_rec37139_37053_37139_r-v1.bsp spk_psp_rec37241_37138_37241_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_psp31.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 35992 2014-04-01T01:43:52.814 -0.000 0.000 -0.000 36010 2014-04-02T11:21:52.814 0.001 0.000 0.001 36031 2014-04-04T02:36:52.814 -0.002 -0.000 -0.002 36051 2014-04-05T15:59:52.814 0.000 0.000 0.001 36064 2014-04-06T15:08:52.814 -0.001 -0.000 0.001 36085 2014-04-08T07:36:52.814 0.000 0.000 0.000 36104 2014-04-09T19:08:52.814 -0.001 0.000 -0.001 36122 2014-04-11T04:50:52.814 -0.003 0.000 -0.002 36139 2014-04-12T12:20:02.814 0.001 -0.000 0.001 36156 2014-04-13T19:22:52.814 -0.000 0.000 0.000 36176 2014-04-15T09:48:52.814 0.000 0.000 0.000 36193 2014-04-16T17:35:52.814 -0.001 -0.000 -0.001 36215 2014-04-18T10:44:52.814 0.001 0.000 0.001 36232 2014-04-19T18:18:52.814 -0.001 -0.000 -0.001 36246 2014-04-20T19:28:52.814 -0.001 0.000 0.001 36266 2014-04-22T10:08:52.814 -0.001 0.000 -0.001 36282 2014-04-23T15:48:52.814 0.000 0.000 0.000 36305 2014-04-25T11:03:52.814 0.000 0.000 0.000 36321 2014-04-26T16:58:52.814 0.000 0.000 0.000 36336 2014-04-27T19:53:52.814 -0.002 0.000 0.001 36355 2014-04-29T08:24:52.814 -0.005 -0.000 -0.003 36376 2014-04-30T23:48:52.814 0.001 -0.000 0.001 36396 2014-05-02T13:11:52.814 0.001 0.000 0.001 36414 2014-05-03T21:43:52.814 -0.002 -0.000 0.001 36434 2014-05-05T10:35:52.814 0.002 0.000 0.001 36451 2014-05-06T20:03:52.814 0.000 0.000 0.000 36469 2014-05-08T05:42:52.814 -0.006 -0.000 -0.003 36482 2014-05-09T05:58:52.814 0.006 0.000 0.003 36501 2014-05-10T17:06:52.814 0.006 0.000 0.000 36526 2014-05-12T14:40:52.814 -0.007 -0.000 -0.003 36543 2014-05-13T22:28:52.814 -0.005 -0.000 -0.002 36563 2014-05-15T11:53:52.814 0.005 -0.000 0.002 36581 2014-05-16T21:34:52.814 -0.002 0.000 -0.001 36593 2014-05-17T20:01:52.814 0.003 0.000 0.001 36605 2014-05-18T18:58:52.814 -0.002 0.000 0.001 36625 2014-05-20T07:48:52.814 -0.006 -0.000 -0.003 36646 2014-05-21T23:10:52.814 0.001 0.000 0.001 36665 2014-05-23T10:43:52.814 -0.003 -0.000 -0.001 36683 2014-05-24T20:23:52.814 -0.001 0.000 -0.000 36695 2014-05-25T19:18:52.814 -0.004 0.000 0.002 36710 2014-05-26T22:53:52.814 -0.004 -0.000 -0.001 36723 2014-05-27T23:13:52.814 0.001 0.000 0.000 36741 2014-05-29T08:43:52.815 0.008 0.000 0.004 36756 2014-05-30T12:57:52.815 0.002 0.000 0.001 36767 2014-05-31T10:05:52.815 -0.003 0.000 0.002 36786 2014-06-01T21:03:52.815 -0.003 -0.000 -0.001 36806 2014-06-03T10:28:52.815 -0.006 -0.000 -0.002 36823 2014-06-04T19:32:57.815 0.004 -0.000 0.001 36839 2014-06-06T00:12:22.815 0.001 -0.000 0.000 36856 2014-06-07T07:58:52.815 0.005 -0.000 0.002 36874 2014-06-08T18:14:52.815 -0.005 0.000 0.002 36894 2014-06-10T07:04:52.815 0.007 -0.000 0.003 36909 2014-06-11T11:07:52.815 -0.005 -0.000 -0.002 36928 2014-06-12T22:40:52.815 0.008 0.000 0.003 36944 2014-06-14T04:41:52.815 -0.001 -0.000 -0.000 36959 2014-06-15T09:29:22.815 0.007 -0.000 -0.003 36975 2014-06-16T14:27:52.815 -0.000 -0.000 -0.000 36992 2014-06-17T22:20:52.815 -0.002 0.000 -0.001 37011 2014-06-19T09:53:52.815 0.009 0.000 0.004 37026 2014-06-20T14:01:22.815 -0.004 0.000 -0.001 37042 2014-06-21T19:55:22.815 -0.005 -0.000 -0.002 37053 2014-06-22T17:03:22.815 -0.006 0.000 0.003 37072 2014-06-24T03:57:52.815 0.004 -0.000 0.002 37088 2014-06-25T09:53:22.815 -0.006 -0.000 -0.003 37102 2014-06-26T12:03:52.815 -0.000 -0.000 -0.000 37120 2014-06-27T21:58:52.815 -0.005 0.000 -0.001 37138 2014-06-29T07:48:52.815 0.001 0.000 -0.000 37158 2014-06-30T20:53:52.815 0.002 0.000 0.001