Mars Reconnaissance Orbiter Primary Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Wed Apr 25 14:41:57 PDT 2007 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 Primary Science Phase of the MRO mission (orbits 601 through 2022): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2006 SEP 12 06:40:00.000 2007 JAN 01 01:01:05.183 Status -------------------------------------------------------- This file was created by merging regular reconstructed OD solution SPK files produced by the MRO NAV team during the Primary 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_rec00681_00600_00681_r-v1.bsp spk_psp_rec00765_00681_00765_r-v1.bsp spk_psp_rec00887_00765_00887_r-v1.bsp spk_psp_rec00955_00886_00955_r-v1.bsp spk_psp_rec01235_00954_01235_r-v1.bsp spk_psp_rec01315_01233_01315_r-v1.bsp spk_psp_rec01378_01314_01378_r-v1.bsp spk_psp_rec01477_01378_01477_r-v1.bsp spk_psp_rec01562_01477_01562_r-v1.bsp spk_psp_rec01674_01561_01674_r-v1.bsp spk_psp_rec01754_01673_01754_r-v1.bsp spk_psp_rec01819_01753_01819_r-v1.bsp spk_psp_rec01897_01818_01897_r-v1.bsp spk_psp_rec01972_01896_01972_r-v1.bsp spk_psp_rec02028_01970_02028_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_psp1.bsp: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 613 2006-09-13T06:38:54.817 -0.009 -0.000 0.007 626 2006-09-14T06:48:54.817 0.008 -0.000 -0.006 640 2006-09-15T08:48:54.817 0.007 -0.000 -0.003 653 2006-09-16T09:18:54.817 0.001 0.000 -0.001 666 2006-09-17T09:33:54.817 -0.013 0.000 0.010 681 2006-09-18T13:36:54.817 -0.000 0.000 0.000 699 2006-09-19T22:58:54.817 -0.010 -0.000 0.002 712 2006-09-20T23:38:54.817 0.006 -0.000 -0.005 728 2006-09-22T05:18:54.817 0.004 -0.000 -0.002 748 2006-09-23T19:03:54.817 -0.017 0.000 0.013 765 2006-09-25T02:33:54.817 0.010 -0.000 -0.008 781 2006-09-26T08:43:54.817 -0.001 0.000 0.001 797 2006-09-27T14:18:54.817 0.007 0.000 -0.005 811 2006-09-28T16:28:54.817 -0.008 -0.000 0.006 829 2006-09-30T02:08:54.817 0.006 -0.000 -0.005 846 2006-10-01T09:38:54.817 -0.004 -0.000 0.001 860 2006-10-02T12:03:54.817 0.002 0.000 -0.002 875 2006-10-03T16:03:54.817 -0.002 0.000 0.001 886 2006-10-04T12:28:54.817 0.004 0.000 -0.002 901 2006-10-05T16:38:54.817 -0.005 -0.000 0.003 911 2006-10-06T11:18:54.817 0.007 -0.000 -0.005 928 2006-10-07T19:06:54.817 0.006 0.000 -0.005 936 2006-10-08T09:58:54.817 -0.006 -0.000 0.004 954 2006-10-09T19:43:54.817 0.004 -0.000 -0.004 970 2006-10-11T01:28:54.817 0.008 0.001 -0.004 989 2006-10-12T13:06:54.817 0.004 0.000 -0.003 1014 2006-10-14T11:50:54.817 -0.012 0.000 0.011 1047 2006-10-17T01:28:54.817 0.006 0.002 -0.005 1198 2006-10-28T19:38:54.817 -0.000 0.002 -0.002 1233 2006-10-31T13:28:54.817 -0.005 -0.002 -0.000 1251 2006-11-01T22:28:54.817 -0.001 -0.001 0.000 1271 2006-11-03T11:58:54.817 -0.005 -0.000 0.005 1296 2006-11-05T10:43:54.817 0.004 -0.001 -0.004 1314 2006-11-06T20:23:54.817 -0.005 -0.000 0.004 1337 2006-11-08T16:13:54.817 0.004 -0.000 0.003 1356 2006-11-10T02:50:54.817 -0.003 -0.000 0.002 1378 2006-11-11T19:58:54.817 0.000 0.000 0.000 1392 2006-11-12T21:58:54.817 -0.010 -0.000 0.006 1408 2006-11-14T03:43:54.817 0.005 0.001 -0.001 1434 2006-11-16T04:33:54.817 0.003 -0.000 -0.003 1454 2006-11-17T17:58:54.817 0.001 -0.000 -0.001 1477 2006-11-19T12:57:24.817 -0.003 -0.000 0.003 1498 2006-11-21T04:08:54.817 0.001 0.000 -0.001 1520 2006-11-22T21:16:24.817 -0.002 0.000 0.002 1541 2006-11-24T12:28:54.817 0.004 0.000 -0.003 1561 2006-11-26T01:51:54.817 -0.000 -0.000 0.000 1583 2006-11-27T19:23:54.816 0.000 0.000 0.000 1599 2006-11-29T00:48:54.816 -0.003 -0.000 0.002 1613 2006-11-30T02:58:54.816 0.003 0.002 -0.002 1642 2006-12-02T09:43:54.816 -0.001 -0.000 -0.000 1673 2006-12-04T19:28:54.816 0.001 -0.000 -0.001 1687 2006-12-05T21:28:54.816 -0.003 0.000 0.003 1701 2006-12-06T23:28:54.816 0.002 -0.000 -0.002 1720 2006-12-08T10:58:54.816 0.002 0.000 -0.002 1733 2006-12-09T11:13:54.816 0.002 0.000 -0.002 1753 2006-12-11T00:38:54.816 -0.006 -0.000 0.006 1767 2006-12-12T02:43:54.816 -0.004 -0.000 0.004 1787 2006-12-13T16:51:24.816 -0.001 -0.000 -0.001 1804 2006-12-14T23:54:54.816 -0.001 -0.000 0.001 1818 2006-12-16T02:03:54.816 -0.001 -0.000 0.000 1838 2006-12-17T15:28:54.816 0.000 0.000 -0.000 1856 2006-12-19T01:08:54.816 0.001 0.000 -0.001 1877 2006-12-20T16:23:54.816 0.002 -0.000 -0.002 1896 2006-12-22T04:44:54.816 -0.001 -0.000 -0.001 1915 2006-12-23T15:27:54.816 0.001 -0.000 -0.001 1933 2006-12-25T01:06:54.816 0.001 0.000 -0.001 1951 2006-12-26T10:46:54.816 -0.001 0.000 0.001 1970 2006-12-27T22:18:54.816 -0.001 -0.000 0.001 1989 2006-12-29T09:53:54.816 0.000 -0.000 -0.000 2007 2006-12-30T19:28:54.816 0.001 -0.000 -0.001