Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Tue Nov 9 15:19:52 PST 2010 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 18411 through 19590): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2010 JUL 01 00:01:06.184 2010 OCT 01 01:01:06.182 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_rec18455_18367_18455_r-v1.bsp spk_psp_rec18552_18453_18552_r-v1.bsp spk_psp_rec18636_18550_18636_r-v1.bsp spk_psp_rec18729_18635_18729_r-v1.bsp spk_psp_rec18807_18727_18807_r-v1.bsp spk_psp_rec18910_18805_18910_r-v1.bsp spk_psp_rec18993_18908_18993_r-v1.bsp spk_psp_rec19091_18991_19091_r-v1.bsp spk_psp_rec19194_19090_19194_r-v1.bsp spk_psp_rec19266_19192_19266_r-v1.bsp spk_psp_rec19359_19264_19359_r-v1.bsp spk_psp_rec19405_19317_19405_r-v1.bsp spk_psp_rec19528_19402_19528_r-v1.bsp spk_psp_rec19614_19526_19614_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_psp16.bsp: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 18420 2010-07-01T18:44:53.815 -0.009 0.000 0.000 18438 2010-07-03T04:11:53.815 -0.003 0.000 -0.001 18453 2010-07-04T08:46:53.815 -0.002 -0.000 0.001 18472 2010-07-05T19:51:53.816 0.012 -0.000 0.002 18486 2010-07-06T21:59:53.816 -0.008 -0.000 -0.002 18499 2010-07-07T22:19:53.816 0.000 -0.000 0.000 18513 2010-07-09T01:58:53.816 -0.001 0.000 -0.000 18533 2010-07-10T13:43:53.816 0.004 0.000 0.002 18550 2010-07-11T22:05:53.816 0.009 -0.000 -0.004 18566 2010-07-13T04:54:53.816 -0.001 -0.000 -0.000 18586 2010-07-14T16:56:53.816 0.002 0.000 0.001 18604 2010-07-16T02:35:53.816 -0.007 -0.000 -0.003 18619 2010-07-17T06:52:53.816 -0.005 -0.000 0.000 18635 2010-07-18T13:03:53.816 -0.006 0.000 0.003 18658 2010-07-20T07:35:53.816 -0.012 0.000 -0.004 18672 2010-07-21T09:45:53.816 0.013 -0.000 0.004 18691 2010-07-22T21:17:53.816 -0.004 -0.000 -0.002 18710 2010-07-24T10:23:53.816 0.001 -0.000 0.001 18727 2010-07-25T17:08:53.816 0.005 -0.000 -0.002 18746 2010-07-27T04:18:53.816 -0.010 -0.000 -0.001 18758 2010-07-28T02:33:53.816 0.005 0.000 0.002 18771 2010-07-29T02:50:53.816 0.002 -0.000 0.001 18787 2010-07-30T10:23:53.816 -0.011 -0.000 -0.006 18805 2010-07-31T18:58:53.816 0.006 -0.000 -0.003 18825 2010-08-02T07:52:53.816 0.010 0.000 0.004 18843 2010-08-03T17:22:53.816 -0.002 -0.000 -0.001 18857 2010-08-04T19:45:53.816 -0.001 -0.000 -0.000 18874 2010-08-06T03:48:53.816 0.005 -0.000 -0.001 18894 2010-08-07T16:58:53.816 0.001 0.000 0.000 18908 2010-08-08T19:28:53.816 0.005 0.000 -0.002 18929 2010-08-10T10:28:53.816 0.001 0.000 0.000 18951 2010-08-12T03:38:53.816 -0.003 -0.000 -0.000 18973 2010-08-13T20:43:53.817 -0.008 -0.000 -0.002 18991 2010-08-15T06:49:53.817 0.009 0.000 -0.005 19011 2010-08-16T19:42:53.817 -0.005 -0.000 -0.002 19031 2010-08-18T10:28:53.817 0.012 -0.000 0.004 19049 2010-08-19T18:45:53.817 -0.010 -0.000 -0.004 19066 2010-08-21T02:58:53.817 0.006 -0.000 -0.002 19079 2010-08-22T03:50:53.817 -0.006 0.000 0.002 19090 2010-08-22T23:54:53.817 0.003 0.000 -0.001 19113 2010-08-24T18:25:53.817 0.002 0.000 0.001 19125 2010-08-25T16:52:53.817 0.009 0.000 0.003 19139 2010-08-26T19:03:53.817 0.006 0.000 0.002 19156 2010-08-28T02:58:53.817 -0.001 0.000 -0.000 19175 2010-08-29T14:28:53.817 -0.001 0.000 -0.000 19192 2010-08-30T22:43:53.817 0.002 -0.000 -0.001 19210 2010-09-01T09:28:53.817 0.001 0.000 0.001 19231 2010-09-03T00:48:53.817 -0.021 -0.000 -0.011 19250 2010-09-04T10:38:53.817 0.013 0.000 0.005 19264 2010-09-05T13:11:53.817 -0.003 0.000 0.001 19282 2010-09-06T22:28:53.817 -0.002 0.000 -0.000 19299 2010-09-08T07:34:53.817 0.003 -0.000 0.001 19317 2010-09-09T16:20:53.817 -0.005 0.000 0.002 19336 2010-09-11T03:26:53.817 0.002 0.000 0.001 19346 2010-09-11T22:11:53.817 -0.006 0.000 -0.002 19359 2010-09-12T22:26:53.817 -0.010 0.000 -0.004 19377 2010-09-14T08:24:53.817 0.007 0.000 -0.001 19398 2010-09-15T23:28:53.817 0.005 -0.001 0.001 19402 2010-09-16T07:43:53.817 -0.014 0.000 0.006 19420 2010-09-17T18:08:53.817 -0.015 0.000 -0.008 19437 2010-09-19T02:03:53.817 0.000 0.000 0.000 19454 2010-09-20T09:38:53.817 0.007 -0.000 0.003 19471 2010-09-21T15:53:53.817 -0.006 -0.000 -0.002 19493 2010-09-23T09:02:53.817 0.008 0.000 0.002 19510 2010-09-24T18:21:53.817 -0.003 -0.000 -0.002 19526 2010-09-25T23:10:53.817 0.001 -0.000 -0.000 19542 2010-09-27T04:39:53.817 0.004 0.000 0.001 19559 2010-09-28T12:31:53.817 0.001 -0.000 0.000 19576 2010-09-29T20:12:53.817 -0.005 0.000 -0.002