Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Tue Aug 24 08:10:53 PDT 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 17243 through 18410): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2010 APR 01 00:01:06.185 2010 JUL 01 01:01:06.184 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_rec17282_17202_17282_r-v1.bsp spk_psp_rec17383_17280_17383_r-v1.bsp spk_psp_rec17485_17382_17485_r-v1.bsp spk_psp_rec17571_17484_17571_r-v1.bsp spk_psp_rec17642_17569_17642_r-v1.bsp spk_psp_rec17749_17641_17749_r-v1.bsp spk_psp_rec17836_17747_17836_r-v1.bsp spk_psp_rec17925_17832_17925_r-v1.bsp spk_psp_rec17992_17921_17992_r-v1.bsp spk_psp_rec18078_17990_18078_r-v1.bsp spk_psp_rec18177_18077_18177_r-v1.bsp spk_psp_rec18281_18175_18281_r-v1.bsp spk_psp_rec18369_18279_18369_r-v1.bsp spk_psp_rec18455_18367_18455_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_psp15.bsp: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 17243 2010-04-01T00:13:53.814 0.002 -0.000 -0.001 17261 2010-04-02T11:56:53.814 -0.008 0.000 0.001 17280 2010-04-03T23:16:53.814 0.008 -0.000 -0.002 17299 2010-04-05T11:19:53.814 -0.008 -0.000 -0.001 17313 2010-04-06T13:14:53.814 0.011 0.000 -0.001 17326 2010-04-07T14:04:28.814 -0.003 -0.000 -0.001 17345 2010-04-09T00:15:13.814 -0.003 -0.000 -0.000 17363 2010-04-10T09:47:57.814 -0.008 -0.000 -0.001 17382 2010-04-11T21:35:53.814 -0.003 -0.000 0.000 17405 2010-04-13T16:23:53.814 0.004 -0.000 0.000 17427 2010-04-15T10:28:53.814 0.004 -0.000 -0.000 17447 2010-04-16T22:53:53.814 0.009 0.000 0.001 17467 2010-04-18T12:20:53.814 0.001 -0.000 0.000 17484 2010-04-19T20:26:53.814 0.002 0.000 -0.001 17500 2010-04-21T02:00:53.814 -0.002 -0.000 -0.000 17511 2010-04-21T23:48:53.814 -0.006 -0.000 -0.001 17531 2010-04-23T12:48:53.814 -0.001 0.000 0.000 17549 2010-04-24T23:13:53.814 -0.016 -0.000 -0.006 17569 2010-04-26T11:32:23.814 0.005 -0.000 -0.002 17591 2010-04-28T04:15:53.814 0.010 0.000 0.001 17608 2010-04-29T12:02:53.814 0.004 0.000 0.001 17625 2010-04-30T19:58:53.814 -0.011 0.000 0.000 17641 2010-05-02T02:01:53.814 0.013 -0.000 -0.002 17658 2010-05-03T09:34:53.814 -0.005 -0.000 -0.001 17676 2010-05-04T19:14:53.814 -0.001 -0.000 -0.000 17694 2010-05-06T04:53:53.814 -0.010 -0.000 -0.002 17715 2010-05-07T20:08:53.814 -0.008 0.000 -0.002 17731 2010-05-09T01:48:53.814 -0.011 -0.000 -0.004 17747 2010-05-10T08:28:53.814 0.008 -0.000 -0.003 17768 2010-05-11T23:14:53.814 0.010 0.000 0.002 17782 2010-05-13T01:25:53.814 -0.004 0.000 -0.001 17802 2010-05-14T14:52:08.814 0.006 -0.000 0.001 17818 2010-05-15T20:47:53.814 -0.001 -0.000 -0.000 17832 2010-05-16T23:28:53.814 -0.026 0.000 0.011 17845 2010-05-17T23:58:53.814 -0.019 0.000 0.008 17858 2010-05-18T23:46:53.814 0.003 -0.000 -0.000 17870 2010-05-19T23:22:53.814 0.005 -0.000 0.002 17883 2010-05-20T23:39:53.814 -0.006 -0.000 -0.002 17902 2010-05-22T10:58:53.814 0.014 -0.000 0.000 17921 2010-05-23T21:58:53.814 -0.011 0.000 0.005 17940 2010-05-25T08:41:53.814 -0.014 -0.000 -0.006 17958 2010-05-26T18:26:53.814 -0.007 -0.000 -0.003 17973 2010-05-27T22:38:17.814 0.011 0.000 0.003 17990 2010-05-29T06:43:53.815 -0.005 0.000 0.001 18011 2010-05-30T23:13:53.815 0.010 0.000 0.004 18031 2010-06-01T11:08:53.815 -0.006 -0.000 -0.001 18046 2010-06-02T16:33:53.815 0.021 0.000 0.008 18063 2010-06-03T23:08:53.815 -0.005 -0.000 0.000 18077 2010-06-05T01:28:53.815 -0.002 -0.000 0.000 18100 2010-06-06T20:23:53.815 -0.005 -0.000 0.001 18121 2010-06-08T11:28:53.815 0.002 -0.000 0.000 18139 2010-06-09T21:18:53.815 -0.001 -0.000 0.000 18157 2010-06-11T06:29:53.815 -0.004 -0.000 -0.002 18175 2010-06-12T17:12:53.815 -0.009 0.000 0.004 18192 2010-06-14T00:07:53.815 -0.001 0.000 -0.000 18211 2010-06-15T11:31:53.815 0.006 0.000 0.003 18229 2010-06-16T22:27:53.815 0.000 0.000 -0.000 18249 2010-06-18T10:48:53.815 -0.002 0.000 -0.001 18266 2010-06-19T19:08:53.815 0.004 -0.000 -0.002 18279 2010-06-20T19:35:53.815 0.006 -0.000 -0.003 18306 2010-06-22T21:17:53.815 0.010 0.000 0.004 18319 2010-06-23T22:26:53.815 -0.004 0.000 0.002 18334 2010-06-25T01:36:53.815 -0.004 -0.000 -0.002 18354 2010-06-26T15:22:53.815 -0.004 -0.000 0.001 18367 2010-06-27T15:53:53.815 -0.005 -0.000 0.002 18385 2010-06-29T01:17:53.815 -0.004 0.000 0.000 18402 2010-06-30T09:05:53.815 0.004 0.000 -0.000