Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Mon Feb 4 17:00:21 PST 2013 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 28973 through 30152): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2012 OCT 01 00:01:07.182 2013 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_rec29061_28962_29061_r-v1.bsp spk_psp_rec29148_29059_29148_r-v1.bsp spk_psp_rec29238_29146_29238_r-v1.bsp spk_psp_rec29313_29237_29313_r-v1.bsp spk_psp_rec29421_29312_29421_r-v1.bsp spk_psp_rec29504_29419_29504_r-v1.bsp spk_psp_rec29597_29502_29597_r-v1.bsp spk_psp_rec29689_29596_29689_r-v1.bsp spk_psp_rec29779_29688_29779_r-v1.bsp spk_psp_rec29854_29778_29854_r-v1.bsp spk_psp_rec29943_29852_29943_r-v1.bsp spk_psp_rec30050_29942_30050_r-v1.bsp spk_psp_rec30139_30049_30139_r-v1.bsp spk_psp_rec30222_30138_30222_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_psp25.bsp: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 28981 2012-10-01T17:58:52.817 0.010 0.000 0.003 29003 2012-10-03T10:33:52.817 -0.002 0.000 -0.000 29023 2012-10-04T22:53:52.817 0.006 0.000 0.001 29036 2012-10-05T23:12:52.817 0.010 0.000 0.001 29048 2012-10-06T21:38:52.817 -0.009 -0.000 -0.001 29059 2012-10-07T19:17:52.817 0.007 0.000 0.000 29080 2012-10-09T10:39:52.817 -0.006 -0.000 -0.001 29097 2012-10-10T18:12:52.817 -0.007 0.000 0.001 29114 2012-10-12T01:51:52.817 0.004 -0.000 -0.001 29127 2012-10-13T02:48:52.817 -0.004 0.000 -0.001 29146 2012-10-14T13:13:52.817 -0.003 -0.000 0.000 29157 2012-10-15T09:26:22.817 0.011 0.001 0.002 29174 2012-10-16T18:09:52.817 0.002 -0.000 -0.000 29189 2012-10-17T22:20:22.817 0.004 0.000 0.000 29204 2012-10-19T01:20:22.817 0.004 -0.000 0.000 29218 2012-10-20T04:47:52.817 -0.000 -0.000 -0.000 29237 2012-10-21T15:23:52.817 0.002 -0.000 -0.000 29253 2012-10-22T22:18:52.817 -0.007 0.000 -0.001 29266 2012-10-23T21:23:52.817 0.006 0.000 -0.000 29280 2012-10-24T23:33:52.817 -0.007 -0.000 0.000 29294 2012-10-26T01:53:52.817 -0.003 0.000 0.000 29312 2012-10-27T11:43:52.817 -0.001 -0.000 0.000 29331 2012-10-28T23:03:52.817 -0.005 0.000 0.001 29347 2012-10-30T05:48:52.817 -0.003 0.000 -0.000 29363 2012-10-31T10:43:52.817 0.007 -0.000 -0.000 29378 2012-11-01T14:38:52.817 0.003 0.000 0.000 29394 2012-11-02T20:33:52.817 0.005 -0.000 0.000 29408 2012-11-03T22:45:52.817 0.003 -0.000 0.000 29419 2012-11-04T19:38:52.817 -0.000 0.000 0.000 29434 2012-11-06T01:13:52.817 0.002 0.000 0.000 29450 2012-11-07T07:08:52.817 0.002 0.000 0.000 29472 2012-11-09T00:16:57.817 -0.001 -0.000 -0.000 29486 2012-11-10T00:51:52.817 0.001 0.000 -0.000 29502 2012-11-11T06:45:52.817 0.004 0.000 -0.001 29522 2012-11-12T20:55:52.817 -0.002 -0.000 -0.000 29535 2012-11-13T21:27:52.817 0.004 -0.000 0.001 29553 2012-11-15T06:55:52.817 -0.006 -0.000 -0.000 29574 2012-11-16T22:58:52.817 -0.001 -0.000 -0.000 29596 2012-11-18T14:33:52.817 0.001 0.000 -0.000 29614 2012-11-20T01:23:52.817 0.003 0.000 0.001 29629 2012-11-21T05:53:52.817 0.001 -0.000 0.000 29647 2012-11-22T14:34:52.817 -0.002 -0.000 0.000 29667 2012-11-24T04:50:32.817 0.004 0.000 0.000 29688 2012-11-25T19:08:52.817 0.006 0.000 -0.001 29707 2012-11-27T06:53:52.817 0.003 -0.000 0.000 29722 2012-11-28T10:05:52.816 -0.004 0.000 0.001 29735 2012-11-29T10:23:52.816 -0.004 0.000 0.000 29747 2012-11-30T10:23:52.816 0.000 0.000 0.000 29762 2012-12-01T14:27:52.816 -0.001 -0.000 -0.000 29778 2012-12-02T18:48:52.816 0.000 0.000 -0.000 29792 2012-12-03T22:34:52.816 0.004 0.000 0.000 29812 2012-12-05T10:18:52.816 -0.007 0.000 0.001 29832 2012-12-07T01:16:47.816 0.002 -0.000 0.000 29852 2012-12-08T13:13:52.816 0.004 0.000 -0.001 29871 2012-12-10T01:11:22.816 -0.003 0.000 0.001 29888 2012-12-11T09:17:47.816 -0.003 0.000 -0.000 29907 2012-12-12T21:32:47.816 0.003 0.000 0.001 29922 2012-12-14T01:28:52.816 -0.001 0.000 -0.000 29942 2012-12-15T13:27:52.816 -0.010 0.000 0.002 29958 2012-12-16T19:50:52.816 -0.000 0.000 0.000 29968 2012-12-17T15:36:52.816 -0.002 0.000 -0.000 29991 2012-12-19T09:50:52.816 -0.000 0.000 -0.000 30010 2012-12-20T22:08:27.816 0.002 0.000 0.001 30029 2012-12-22T09:38:32.816 0.001 0.000 0.000 30049 2012-12-23T21:38:52.816 -0.000 -0.000 0.000 30069 2012-12-25T12:28:52.816 -0.004 0.001 -0.001 30089 2012-12-27T00:48:52.816 -0.002 -0.000 0.001 30106 2012-12-28T09:56:52.816 0.001 -0.000 -0.000 30124 2012-12-29T19:37:52.816 -0.003 -0.000 0.001 30138 2012-12-30T20:03:52.816 -0.002 0.000 0.001