MAVEN Reconstructed SPK, NAV Solution, 2019-04-01 to 2019-07-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Thu Aug 8 07:49:37 PDT 2019 Objects in the Ephemeris -------------------------------------------------------- This SPK file contains ephemeris data for the Mars Atmosphere and Volatile Evolution Mission (MAVEN) spacecraft. The NAIF ID code for MAVEN is -202. Approximate Time Coverage -------------------------------------------------------- This file covers the following part of the orbital phase of the MAVEN mission (orbits 8821 through 9416): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2019 APR 01 00:01:09.185 2019 JUL 01 01:01:09.184 Status -------------------------------------------------------- This file was created by merging regular reconstructed OD solution SPK files produced by the MAVEN NAV team during the orbital 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 MAVEN project data base by the MAVEN 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 DE430 planetary ephemeris and MAR097 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: trj_orb_08811-08832_rec_v1.bsp trj_orb_08832-08848_rec_v1.bsp trj_orb_08848-08873_rec_v1.bsp trj_orb_08872-08918_rec_v1.bsp trj_orb_08917-08958_rec_v1.bsp trj_orb_08957-09009_rec_v1.bsp trj_orb_09008-09061_rec_v1.bsp trj_orb_09060-09100_rec_v1.bsp trj_orb_09096-09128_rec_v1.bsp trj_orb_09127-09199_rec_v1.bsp trj_orb_09198-09244_rec_v1.bsp trj_orb_09244-09290_rec_v1.bsp trj_orb_09290-09326_rec_v1.bsp trj_orb_09325-09383_rec_v1.bsp trj_orb_09382-09418_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 ./maven_orb_rec_190401_190701_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 8824 2019-04-01T13:44:50.814 0.004 -0.001 -0.001 8827 2019-04-02T02:24:50.814 0.046 0.010 -0.039 8832 2019-04-02T19:00:50.814 0.028 -0.011 -0.003 8835 2019-04-03T06:03:50.814 -0.006 0.003 0.001 8839 2019-04-03T20:43:50.814 0.006 -0.003 -0.001 8848 2019-04-05T05:43:50.814 -0.033 0.013 0.002 8851 2019-04-05T16:43:50.814 0.003 -0.001 0.000 8866 2019-04-07T23:42:50.814 -0.009 0.003 -0.001 8872 2019-04-08T22:03:50.814 0.002 -0.001 -0.001 8879 2019-04-10T00:13:50.814 -0.056 0.014 0.026 8885 2019-04-10T21:48:50.814 0.039 -0.016 -0.008 8893 2019-04-12T04:28:50.814 0.001 -0.000 -0.001 8898 2019-04-12T21:10:50.814 0.078 -0.032 0.014 8908 2019-04-14T11:41:50.814 -0.184 -0.049 0.097 8914 2019-04-15T09:16:50.814 0.065 0.004 -0.028 8917 2019-04-15T20:58:47.814 -0.015 -0.005 0.008 8923 2019-04-16T17:19:55.814 0.029 -0.011 -0.002 8931 2019-04-17T22:40:22.814 -0.052 0.019 0.001 8936 2019-04-18T17:08:30.814 -0.039 0.013 0.002 8943 2019-04-19T19:43:50.814 0.051 0.006 -0.016 8950 2019-04-20T19:48:50.814 -0.023 0.009 -0.008 8957 2019-04-21T21:42:50.814 0.004 -0.002 0.001 8963 2019-04-22T19:58:50.814 0.021 -0.008 0.003 8975 2019-04-24T15:58:50.814 -0.045 0.017 -0.009 8983 2019-04-25T23:23:50.814 0.012 0.005 -0.005 8995 2019-04-27T17:28:50.814 0.007 -0.002 0.001 9001 2019-04-28T15:43:50.814 -0.010 0.002 -0.002 9008 2019-04-29T17:09:50.814 -0.015 0.005 -0.004 9014 2019-04-30T16:50:50.814 0.002 0.001 -0.001 9022 2019-05-01T19:50:50.814 0.008 -0.003 0.003 9028 2019-05-02T17:48:50.814 -0.008 0.003 -0.003 9034 2019-05-03T16:27:50.814 -0.004 0.001 -0.001 9039 2019-05-04T09:45:50.814 -0.017 0.003 0.001 9046 2019-05-05T12:28:50.814 -0.020 0.006 -0.008 9050 2019-05-06T03:41:50.814 -0.003 -0.000 -0.001 9060 2019-05-07T16:33:50.814 0.058 0.007 0.017 9063 2019-05-08T02:48:50.814 0.009 -0.002 0.004 9073 2019-05-09T15:43:50.814 -0.015 0.001 -0.007 9081 2019-05-10T20:22:08.837 0.058 -0.021 0.030 9086 2019-05-11T14:40:05.734 -0.049 0.018 -0.026 9093 2019-05-12T16:32:50.814 0.025 -0.007 0.014 9096 2019-05-13T02:43:50.814 0.026 -0.010 0.005 9113 2019-05-15T17:03:50.814 -0.047 0.019 -0.013 9121 2019-05-16T22:33:50.814 -0.001 0.000 -0.000 9127 2019-05-17T21:02:17.814 -0.017 0.005 -0.012 9133 2019-05-18T19:16:27.814 -0.039 0.004 -0.028 9141 2019-05-20T01:36:24.814 0.031 0.012 0.018 9152 2019-05-21T16:28:50.814 0.004 -0.001 0.003 9159 2019-05-22T17:28:50.814 -0.030 0.012 -0.008 9164 2019-05-23T11:58:50.814 0.019 -0.007 0.009 9172 2019-05-24T16:58:50.814 -0.002 0.001 -0.000 9183 2019-05-26T10:37:50.814 -0.009 -0.001 -0.009 9193 2019-05-27T21:41:50.814 0.010 -0.004 -0.002 9198 2019-05-28T16:05:33.815 -0.004 0.001 0.000 9204 2019-05-29T15:48:13.815 -0.041 -0.011 -0.050 9207 2019-05-30T01:23:04.815 0.048 -0.017 0.027 9219 2019-05-31T20:53:50.815 -0.001 0.000 0.000 9224 2019-06-01T14:53:50.815 0.002 -0.001 -0.002 9233 2019-06-03T01:18:50.815 -0.004 0.000 -0.006 9244 2019-06-04T16:08:31.815 0.018 -0.007 -0.016 9253 2019-06-06T01:02:20.815 -0.020 0.008 0.022 9263 2019-06-07T14:24:50.815 0.018 -0.005 0.015 9275 2019-06-09T09:58:50.815 -0.029 0.011 -0.005 9279 2019-06-10T01:13:50.815 0.024 -0.003 0.032 9290 2019-06-11T16:28:50.815 -0.008 0.003 0.010 9299 2019-06-13T01:26:50.815 0.004 -0.002 -0.005 9311 2019-06-14T21:33:50.815 -0.017 0.007 0.007 9316 2019-06-15T15:48:50.815 0.009 -0.004 -0.006 9325 2019-06-17T01:03:23.815 -0.007 0.002 -0.004 9338 2019-06-19T01:47:52.815 -0.009 -0.003 -0.037 9347 2019-06-20T09:23:17.815 0.002 -0.001 -0.001 9357 2019-06-21T21:47:42.815 -0.007 0.003 0.011 9362 2019-06-22T16:20:51.815 0.011 -0.003 0.001 9367 2019-06-23T10:35:19.815 -0.006 0.002 0.001 9371 2019-06-24T00:59:00.128 0.007 -0.003 -0.018 9375 2019-06-24T15:04:16.815 -0.004 0.002 0.041 9382 2019-06-25T16:58:50.815 -0.002 0.001 0.019 9391 2019-06-27T02:08:50.815 -0.001 0.000 0.002 9403 2019-06-28T21:58:50.815 -0.000 0.000 -0.026 9414 2019-06-30T13:38:50.815 0.003 -0.001 0.079 9416 2019-07-01T00:33:50.815 0.002 -0.001 0.044 End of comments.