Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Fri May 22 07:05:09 PDT 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 39522 through 40676): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2015 JAN 01 00:01:08.000 2015 APR 01 01:01:07.185 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_rec39531_39438_39531_r-v1.bsp spk_psp_rec39631_39514_39631_r-v1.bsp spk_psp_rec39733_39630_39733_r-v1.bsp spk_psp_rec39827_39723_39827_r-v1.bsp spk_psp_rec39910_39820_39910_r-v1.bsp spk_psp_rec40005_39903_40005_r-v1.bsp spk_psp_rec40093_39996_40093_r-v1.bsp spk_psp_rec40186_40092_40186_r-v1.bsp spk_psp_rec40274_40175_40274_r-v1.bsp spk_psp_rec40367_40269_40367_r-v1.bsp spk_psp_rec40457_40352_40457_r-v1.bsp spk_psp_rec40540_40453_40540_r-v1.bsp spk_psp_rec40634_40533_40634_r-v1.bsp spk_psp_rec40724_40629_40724_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_psp34.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 39544 2015-01-02T19:15:59.816 -0.002 0.000 -0.000 39559 2015-01-03T23:29:58.815 -0.003 -0.000 0.000 39577 2015-01-05T09:09:45.815 0.007 0.000 -0.001 39596 2015-01-06T20:41:37.815 0.000 0.000 -0.000 39610 2015-01-07T22:52:33.815 -0.007 -0.000 0.001 39619 2015-01-08T15:42:15.815 0.000 -0.000 0.000 39630 2015-01-09T11:44:52.815 0.008 -0.000 0.004 39655 2015-01-11T10:30:52.815 0.000 -0.000 -0.000 39674 2015-01-12T22:32:53.815 -0.005 -0.000 0.001 39684 2015-01-13T17:13:28.815 0.005 -0.000 -0.000 39700 2015-01-14T23:09:03.815 0.002 -0.000 -0.000 39713 2015-01-15T23:27:00.815 -0.004 -0.000 0.000 39718 2015-01-16T08:47:55.815 -0.010 -0.000 0.001 39723 2015-01-16T17:11:52.815 -0.003 -0.000 -0.000 39749 2015-01-18T18:27:52.815 -0.006 0.000 -0.002 39764 2015-01-19T22:47:42.815 -0.002 -0.000 0.000 39774 2015-01-20T17:07:52.815 -0.001 -0.000 -0.001 39783 2015-01-21T09:52:52.815 0.004 -0.000 0.002 39798 2015-01-22T13:38:52.815 -0.004 -0.000 -0.002 39805 2015-01-23T02:33:52.815 -0.007 -0.000 -0.001 39820 2015-01-24T06:08:52.815 0.002 -0.000 -0.001 39836 2015-01-25T13:01:52.815 0.006 0.000 0.003 39849 2015-01-26T13:13:52.815 0.001 -0.000 0.001 39867 2015-01-27T23:03:52.815 0.003 -0.000 0.001 39879 2015-01-28T21:33:52.815 0.001 0.000 0.001 39889 2015-01-29T15:58:52.815 -0.002 -0.000 -0.001 39898 2015-01-30T09:05:52.815 0.001 0.000 0.000 39903 2015-01-30T17:05:22.815 0.008 0.000 -0.004 39928 2015-02-01T17:13:52.815 0.004 0.000 0.002 39944 2015-02-02T23:24:20.815 0.003 -0.000 -0.000 39955 2015-02-03T19:15:24.815 -0.000 0.000 -0.000 39967 2015-02-04T18:25:23.815 -0.006 0.000 0.000 39978 2015-02-05T14:59:23.815 -0.005 0.000 0.000 39984 2015-02-06T01:56:12.815 0.005 0.000 0.002 39996 2015-02-06T23:22:19.815 -0.002 -0.000 0.001 40019 2015-02-08T19:20:20.815 0.003 -0.000 0.001 40036 2015-02-10T02:19:52.814 0.001 0.000 -0.001 40052 2015-02-11T08:48:52.814 0.002 -0.000 0.002 40073 2015-02-13T00:05:52.814 0.006 0.000 0.005 40092 2015-02-14T11:43:52.814 0.001 -0.000 -0.000 40109 2015-02-15T19:18:52.814 -0.001 0.000 -0.001 40128 2015-02-17T06:56:52.814 -0.002 0.000 -0.001 40142 2015-02-18T09:02:52.814 -0.001 -0.000 -0.001 40158 2015-02-19T15:19:52.814 0.001 -0.000 0.001 40173 2015-02-20T19:03:52.814 0.002 -0.000 0.001 40175 2015-02-20T21:54:52.814 0.003 -0.000 -0.002 40199 2015-02-22T19:25:52.814 -0.003 0.000 -0.000 40211 2015-02-23T17:47:51.644 -0.003 -0.000 0.000 40226 2015-02-24T22:30:02.814 -0.001 -0.000 -0.000 40237 2015-02-25T19:02:24.834 0.004 -0.000 0.002 40250 2015-02-26T19:00:52.814 0.001 -0.000 0.001 40269 2015-02-28T05:48:52.814 -0.002 0.000 0.002 40290 2015-03-01T22:28:52.814 0.004 -0.000 0.000 40308 2015-03-03T07:50:16.354 0.002 0.000 0.001 40324 2015-03-04T13:45:09.994 -0.000 0.000 -0.000 40340 2015-03-05T19:02:51.814 0.002 -0.000 -0.000 40346 2015-03-06T06:56:04.164 0.001 0.000 0.001 40352 2015-03-06T16:55:52.814 0.001 0.000 -0.001 40380 2015-03-08T22:48:52.814 0.001 -0.000 -0.000 40393 2015-03-09T23:08:22.814 -0.002 -0.001 0.000 40405 2015-03-10T21:34:52.814 0.004 -0.000 0.000 40416 2015-03-11T18:08:52.814 -0.001 0.000 -0.000 40430 2015-03-12T19:19:52.814 0.001 0.000 -0.000 40436 2015-03-13T07:32:52.814 -0.001 0.000 0.000 40453 2015-03-14T13:54:40.814 -0.001 0.000 0.001 40470 2015-03-15T23:07:52.814 0.000 0.000 0.000 40478 2015-03-16T13:21:52.814 0.000 -0.000 -0.000 40495 2015-03-17T21:30:52.814 0.002 0.000 0.002 40515 2015-03-19T11:16:52.814 0.002 -0.000 -0.000 40523 2015-03-20T01:35:52.814 0.002 -0.000 0.001 40533 2015-03-20T19:58:52.814 0.002 0.000 -0.000 40555 2015-03-22T13:51:52.814 0.001 -0.000 0.000 40570 2015-03-23T17:45:52.814 0.001 -0.000 0.001 40585 2015-03-24T22:09:52.814 -0.001 0.000 -0.000 40598 2015-03-25T22:28:52.814 0.002 0.000 0.000 40616 2015-03-27T07:58:52.814 0.000 0.000 0.000 40629 2015-03-28T06:56:52.814 -0.001 0.000 0.001 40645 2015-03-29T13:34:52.814 -0.000 -0.000 -0.000 40660 2015-03-30T18:27:40.814 -0.002 0.000 -0.000 40673 2015-03-31T17:49:52.814 -0.002 -0.000 0.000