2001 Mars Odyssey Extended Phase SPK, M01 NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Thu Feb 12 13:28:53 PST 2009 Objects in the Ephemeris -------------------------------------------------------- This SPK file contains ephemeris data for the 2001 Mars Odyssey (M01) spacecraft. The NAIF ID code for M01 is -53. Approximate Time Coverage -------------------------------------------------------- This file covers the following part of the Extended Phase of the M01 mission (orbits 30153 through 31269): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2008 OCT 01 00:01:05.182 2009 JAN 01 01:01:05.183 Status -------------------------------------------------------- This file was created by merging regular reconstructed OD solution SPK files produced by the M01 NAV team during the Extended 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 M01 project data base by the M01 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 DE405 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_m_od30252-30344_rec_v1.bsp spk_m_od30342-30431_rec_v1.bsp spk_m_od30431-30504_rec_v1.bsp spk_m_od30503-30590_rec_v1.bsp spk_m_od30589-30659_rec_v1.bsp spk_m_od30658-30757_rec_v1.bsp spk_m_od30755-30813_rec_v1.bsp spk_m_od30812-30892_rec_v1.bsp spk_m_od30891-31006_rec_v1.bsp spk_m_od31004-31105_rec_v1.bsp spk_m_od31097-31156_rec_v1.bsp spk_m_od31156-31238_rec_v1.bsp spk_m_od31237-31344_rec_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 ./m01_ext17.bsp: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 30174 2008-10-02T19:13:54.817 -0.025 0.000 -0.006 30197 2008-10-04T17:13:54.817 0.012 -0.000 0.003 30212 2008-10-05T22:53:54.817 0.034 -0.000 0.008 30235 2008-10-07T20:43:54.817 -0.023 0.000 0.003 30252 2008-10-09T06:18:54.817 -0.006 0.000 0.001 30274 2008-10-11T01:53:54.817 0.006 0.000 -0.001 30297 2008-10-12T22:38:54.817 0.002 -0.000 0.001 30320 2008-10-14T20:28:54.817 -0.050 0.000 -0.006 30342 2008-10-16T16:38:54.817 0.038 0.000 -0.011 30365 2008-10-18T12:13:54.817 0.005 0.000 -0.001 30385 2008-10-20T05:33:54.817 0.010 0.000 -0.003 30405 2008-10-21T19:28:54.817 0.071 0.000 -0.010 30431 2008-10-23T22:43:54.817 -0.108 -0.001 0.024 30452 2008-10-25T17:13:54.817 -0.063 0.000 -0.013 30478 2008-10-27T21:03:54.817 -0.066 -0.000 0.005 30503 2008-10-29T21:02:54.817 0.007 0.000 -0.002 30528 2008-10-31T23:18:54.817 -0.012 0.000 -0.003 30551 2008-11-02T20:53:54.817 -0.099 0.001 -0.019 30566 2008-11-04T02:18:54.817 0.039 -0.000 0.007 30589 2008-11-06T00:08:54.817 0.058 -0.001 0.008 30612 2008-11-07T20:43:54.817 0.061 0.000 -0.005 30636 2008-11-09T20:38:54.817 0.015 -0.000 0.002 30658 2008-11-11T16:23:54.817 0.067 -0.000 0.011 30683 2008-11-13T17:28:54.817 -0.074 0.000 -0.007 30707 2008-11-15T16:58:54.817 -0.025 0.000 -0.003 30735 2008-11-18T00:03:54.817 0.075 -0.001 -0.001 30755 2008-11-19T16:17:54.817 -0.061 0.000 -0.007 30773 2008-11-21T03:13:54.817 0.047 0.000 -0.000 30796 2008-11-23T01:13:54.817 -0.113 0.001 -0.013 30812 2008-11-24T09:08:54.817 -0.163 -0.000 -0.013 30831 2008-11-25T22:13:54.817 -0.230 0.003 -0.021 30853 2008-11-27T18:08:54.816 0.237 0.000 0.023 30870 2008-11-29T03:48:54.816 -0.066 -0.000 -0.005 30891 2008-11-30T20:56:54.816 -0.317 0.006 -0.029 30904 2008-12-01T21:33:54.816 -0.173 -0.005 0.010 31004 2008-12-10T04:08:54.816 -0.103 -0.001 -0.000 31025 2008-12-11T21:43:54.816 0.022 -0.001 0.000 31044 2008-12-13T11:13:54.816 0.138 -0.000 -0.001 31067 2008-12-15T09:07:54.816 -0.119 -0.000 -0.017 31087 2008-12-17T00:48:54.816 -0.007 -0.000 -0.001 31097 2008-12-17T20:28:54.816 0.011 0.000 0.002 31117 2008-12-19T10:33:54.816 -0.042 -0.001 -0.001 31134 2008-12-20T21:03:54.816 0.065 -0.001 -0.006 31156 2008-12-22T16:08:54.816 -0.017 -0.001 0.003 31177 2008-12-24T09:58:54.816 -0.018 0.000 0.002 31194 2008-12-25T19:53:54.816 0.081 -0.001 0.004 31214 2008-12-27T11:13:54.816 0.012 -0.000 -0.001 31237 2008-12-29T09:03:54.816 -0.007 0.000 -0.001 31255 2008-12-30T20:48:54.816 0.014 0.000 0.003 31262 2008-12-31T10:43:54.816 0.003 0.000 0.001