MAVEN Reconstructed SPK, NAV Solution, 2018-04-01 to 2018-07-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Mon Aug 13 10:21:19 PDT 2018 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 6812 through 7304): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2018 APR 01 00:01:09.185 2018 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_06788-06826_rec_v1.bsp trj_orb_06825-06864_rec_v1.bsp trj_orb_06863-06901_rec_v1.bsp trj_orb_06900-06937_rec_v1.bsp trj_orb_06936-06940_rec_v1.bsp trj_orb_06939-06946_rec_v1.bsp trj_orb_06945-06951_rec_v1.bsp trj_orb_06951-06957_rec_v1.bsp trj_orb_06957-06962_rec_v1.bsp trj_orb_06961-06968_rec_v1.bsp trj_orb_06968-06973_rec_v1.bsp trj_orb_06972-06980_rec_v1.bsp trj_orb_06979-07016_rec_v1.bsp trj_orb_07014-07054_rec_v1.bsp trj_orb_07054-07092_rec_v1.bsp trj_orb_07091-07130_rec_v1.bsp trj_orb_07129-07168_rec_v1.bsp trj_orb_07167-07206_rec_v1.bsp trj_orb_07205-07237_rec_v1.bsp trj_orb_07236-07278_rec_v1.bsp trj_orb_07277-07313_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_180401_180701_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 6815 2018-04-01T15:43:50.814 -0.003 0.001 0.005 6825 2018-04-03T14:18:50.814 -0.001 -0.000 0.004 6835 2018-04-05T10:08:50.814 0.013 0.001 -0.023 6843 2018-04-06T20:38:50.814 -0.035 0.017 0.011 6852 2018-04-08T14:10:50.814 0.028 0.002 -0.042 6863 2018-04-10T14:58:50.814 0.009 -0.001 -0.009 6871 2018-04-12T03:28:50.814 -0.008 -0.002 0.011 6880 2018-04-13T18:58:50.814 0.002 -0.000 -0.002 6885 2018-04-14T17:43:50.814 -0.005 -0.000 0.005 6893 2018-04-16T04:43:50.814 0.009 -0.003 -0.003 6900 2018-04-17T13:46:00.814 0.022 0.011 -0.032 6909 2018-04-19T03:02:50.814 -0.008 0.003 -0.011 6917 2018-04-20T14:56:50.814 0.006 -0.003 0.006 6919 2018-04-21T02:34:38.814 -0.023 -0.010 0.027 6927 2018-04-22T13:29:45.814 0.029 0.002 -0.017 6931 2018-04-23T06:00:21.814 0.004 -0.002 0.002 6933 2018-04-23T15:34:38.814 0.026 -0.007 -0.002 6936 2018-04-24T04:58:50.814 -0.054 0.015 0.004 6939 2018-04-24T17:10:24.814 -0.052 0.025 -0.055 6941 2018-04-25T02:16:59.814 0.012 -0.006 0.010 6945 2018-04-25T19:58:50.814 0.042 -0.022 0.038 6949 2018-04-26T13:43:50.814 0.020 -0.010 0.017 6951 2018-04-27T00:28:50.814 0.056 0.011 -0.031 6955 2018-04-27T16:53:50.814 -0.022 0.008 -0.005 6957 2018-04-28T00:54:20.814 -0.018 0.009 -0.017 6959 2018-04-28T09:40:50.814 0.004 -0.002 0.004 6961 2018-04-28T18:43:50.814 -0.060 0.031 -0.047 6965 2018-04-29T11:58:50.814 0.088 -0.040 0.088 6968 2018-04-30T02:06:50.814 0.161 -0.056 0.039 6971 2018-04-30T14:58:50.814 -0.161 0.070 -0.070 6972 2018-04-30T18:58:50.814 0.129 -0.066 0.096 6973 2018-05-01T01:05:50.814 -0.056 -0.012 0.022 6978 2018-05-01T21:58:50.814 0.078 -0.021 0.014 6979 2018-05-02T03:08:50.814 0.037 0.005 -0.009 6984 2018-05-02T23:02:50.814 0.016 -0.007 0.015 6988 2018-05-03T16:58:50.814 -0.025 0.013 -0.019 6995 2018-05-05T02:28:50.814 -0.027 -0.014 0.024 7003 2018-05-06T12:28:50.814 0.020 0.005 -0.005 7014 2018-05-08T12:58:33.814 0.034 0.014 -0.013 7023 2018-05-10T01:48:09.814 0.017 -0.008 0.014 7025 2018-05-10T13:13:06.814 -0.019 -0.009 0.008 7032 2018-05-11T17:38:40.814 -0.021 0.010 -0.014 7036 2018-05-12T11:28:50.814 0.011 -0.004 0.006 7045 2018-05-14T02:58:50.814 -0.018 0.006 -0.009 7054 2018-05-15T17:28:50.814 -0.013 0.007 -0.010 7061 2018-05-17T01:43:50.814 -0.033 -0.002 -0.008 7069 2018-05-18T12:37:50.814 0.012 0.000 0.004 7074 2018-05-19T08:37:57.814 0.000 -0.000 0.000 7079 2018-05-20T08:34:05.814 0.053 0.007 0.014 7087 2018-05-21T17:38:53.814 -0.013 0.006 -0.007 7091 2018-05-22T12:53:50.814 0.003 0.000 0.001 7097 2018-05-23T16:58:50.814 0.004 0.001 -0.002 7103 2018-05-24T16:58:50.814 -0.068 0.022 -0.040 7109 2018-05-25T21:28:50.814 0.041 0.019 0.004 7118 2018-05-27T13:58:50.814 0.032 0.016 -0.004 7129 2018-05-29T13:03:50.815 0.016 -0.003 0.009 7133 2018-05-30T08:18:50.815 0.003 0.001 0.001 7141 2018-05-31T17:28:50.815 -0.010 0.005 -0.005 7145 2018-06-01T12:28:50.815 -0.014 0.002 -0.008 7151 2018-06-02T14:11:50.815 0.023 -0.011 0.013 7156 2018-06-03T12:16:54.815 0.023 -0.012 0.010 7159 2018-06-04T01:28:00.815 0.024 -0.012 0.007 7161 2018-06-04T12:16:47.815 -0.092 -0.011 -0.051 7167 2018-06-05T13:58:50.815 0.000 -0.000 0.000 7177 2018-06-07T11:48:50.815 -0.013 -0.003 -0.008 7188 2018-06-09T11:43:50.815 0.043 -0.011 0.026 7194 2018-06-10T13:13:50.815 -0.037 0.016 0.002 7199 2018-06-11T11:58:50.815 0.034 -0.017 0.014 7205 2018-06-12T16:11:50.815 0.045 0.005 0.029 7209 2018-06-13T08:18:50.815 -0.013 0.007 -0.003 7215 2018-06-14T11:21:50.815 -0.002 0.001 -0.001 7226 2018-06-16T11:43:50.815 -0.013 0.006 0.003 7231 2018-06-17T11:33:50.815 0.026 -0.003 0.017 7236 2018-06-18T11:31:50.815 -0.043 -0.022 -0.020 7242 2018-06-19T13:58:50.815 0.025 0.013 0.017 7247 2018-06-20T10:28:50.815 0.006 -0.002 0.004 7254 2018-06-21T17:58:50.815 -0.009 0.001 -0.006 7264 2018-06-23T13:06:50.815 0.008 -0.004 -0.000 7269 2018-06-24T11:16:50.815 0.033 -0.017 -0.005 7272 2018-06-25T00:23:50.815 -0.054 0.023 0.025 7275 2018-06-25T14:48:50.815 0.098 -0.032 0.045 7277 2018-06-26T01:41:50.815 -0.065 -0.033 -0.051 7283 2018-06-27T01:28:50.815 0.043 -0.021 -0.013 7290 2018-06-28T11:08:50.815 0.061 0.025 0.052 7299 2018-06-30T00:35:01.815 -0.013 0.006 0.006 7300 2018-06-30T07:06:02.815 0.033 0.006 0.025 End of comments.