MAVEN Reconstructed SPK, NAV Solution, 2015-04-01 to 2015-07-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Thu Jul 30 17:04:09 PDT 2015 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 973 through 1462): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2015 APR 01 00:01:07.185 2015 JUL 01 01:01:08.184 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_00970-00991_rec_v1.bsp trj_orb_00991-01045_rec_v1.bsp trj_orb_01044-01058_rec_v1.bsp trj_orb_01058-01062_rec_v1.bsp trj_orb_01062-01068_rec_v1.bsp trj_orb_01068-01072_rec_v1.bsp trj_orb_01072-01079_rec_v1.bsp trj_orb_01078-01084_rec_v1.bsp trj_orb_01083-01089_rec_v1.bsp trj_orb_01089-01112_rec_v1.bsp trj_orb_01112-01158_rec_v1.bsp trj_orb_01157-01188_rec_v1.bsp trj_orb_01187-01235_rec_v1.bsp trj_orb_01234-01277_rec_v1.bsp trj_orb_01275-01303_rec_v1.bsp trj_orb_01302-01348_rec_v1.bsp trj_orb_01347-01392_rec_v1.bsp trj_orb_01391-01421_rec_v1.bsp trj_orb_01421-01454_rec_v1.bsp trj_orb_01454-01500_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_150401_150701_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 975 2015-04-01T12:28:52.814 -0.016 0.003 0.018 981 2015-04-02T15:08:52.814 0.021 -0.007 -0.011 988 2015-04-03T23:18:52.814 -0.017 0.002 0.020 991 2015-04-04T12:28:52.814 -0.035 0.011 0.026 996 2015-04-05T12:23:52.814 0.016 0.005 -0.039 1002 2015-04-06T15:48:52.814 0.024 0.010 -0.073 1006 2015-04-07T07:38:52.814 -0.030 0.015 -0.026 1011 2015-04-08T07:58:52.814 0.017 0.005 -0.042 1015 2015-04-09T00:58:52.814 -0.019 0.005 0.014 1018 2015-04-09T14:58:52.814 -0.006 0.000 0.009 1024 2015-04-10T17:58:52.814 0.019 -0.002 -0.027 1028 2015-04-11T12:59:59.814 -0.006 -0.002 0.021 1034 2015-04-12T15:29:59.814 -0.030 -0.003 0.072 1039 2015-04-13T14:14:59.814 0.043 0.008 -0.127 1044 2015-04-14T12:49:59.814 -0.006 -0.002 0.019 1049 2015-04-15T11:03:59.814 -0.013 -0.001 0.027 1052 2015-04-16T00:59:59.814 -0.002 -0.001 0.003 1054 2015-04-16T09:59:59.814 0.016 0.003 -0.059 1057 2015-04-16T23:59:59.814 -0.019 -0.007 0.116 1058 2015-04-17T04:02:52.814 0.005 0.001 -0.022 1060 2015-04-17T10:58:52.814 -0.018 0.010 -0.153 1062 2015-04-17T19:58:52.814 0.053 -0.027 0.456 1064 2015-04-18T04:58:52.814 -0.040 0.019 -0.351 1066 2015-04-18T13:53:52.814 0.011 -0.006 0.115 1068 2015-04-18T22:43:52.814 0.012 -0.004 0.133 1070 2015-04-19T07:58:52.814 -0.018 0.010 -0.200 1072 2015-04-19T16:58:52.814 -0.008 0.004 -0.093 1073 2015-04-19T23:28:52.814 -0.016 -0.005 0.126 1074 2015-04-20T03:39:59.814 -0.008 -0.005 0.206 1077 2015-04-20T14:59:59.814 0.008 -0.004 0.168 1078 2015-04-20T21:59:59.814 0.010 0.002 -0.149 1080 2015-04-21T06:23:52.814 0.002 0.001 -0.024 1081 2015-04-21T10:49:59.814 -0.003 0.000 0.043 1083 2015-04-21T19:58:52.814 0.006 0.004 -0.090 1086 2015-04-22T09:28:52.814 -0.018 -0.006 0.582 1089 2015-04-22T20:14:59.814 -0.001 0.000 -0.100 1090 2015-04-23T02:58:52.814 0.001 -0.000 -0.067 1092 2015-04-23T09:29:59.814 -0.000 0.000 -0.009 1093 2015-04-23T13:53:59.814 -0.001 -0.000 0.051 1099 2015-04-24T19:13:52.814 0.004 0.000 0.066 1105 2015-04-25T19:43:52.814 0.002 -0.001 -0.037 1109 2015-04-26T13:28:52.814 -0.006 0.003 0.095 1112 2015-04-27T03:28:52.814 -0.010 0.005 0.085 1120 2015-04-28T14:58:52.814 -0.002 0.001 0.011 1125 2015-04-29T12:58:52.814 0.011 -0.006 -0.083 1130 2015-04-30T13:59:59.814 -0.002 -0.000 -0.008 1137 2015-05-01T20:44:59.814 -0.001 -0.000 -0.003 1141 2015-05-02T14:59:59.814 -0.034 -0.018 -0.144 1146 2015-05-03T12:59:59.814 0.091 0.038 0.252 1154 2015-05-04T22:29:59.814 -0.068 0.031 0.233 1157 2015-05-05T11:58:52.814 -0.004 0.002 0.015 1162 2015-05-06T10:58:52.814 0.005 0.000 -0.005 1168 2015-05-07T12:58:52.814 0.007 -0.003 -0.015 1174 2015-05-08T15:58:52.814 0.009 -0.003 -0.015 1178 2015-05-09T11:18:52.814 -0.022 -0.009 -0.021 1184 2015-05-10T11:58:52.814 -0.012 0.005 0.032 1187 2015-05-11T01:08:52.814 0.022 -0.012 -0.061 1191 2015-05-11T19:58:52.814 -0.006 0.000 0.007 1196 2015-05-12T18:58:52.814 -0.025 -0.005 0.004 1201 2015-05-13T16:58:52.814 0.033 0.001 -0.018 1207 2015-05-14T20:58:52.814 0.001 0.001 0.002 1213 2015-05-15T21:58:52.814 0.013 -0.002 -0.011 1217 2015-05-16T14:49:59.814 0.062 -0.030 -0.117 1221 2015-05-17T08:38:06.814 -0.024 0.011 0.046 1224 2015-05-17T22:58:52.814 -0.037 0.004 0.038 1228 2015-05-18T15:58:52.814 -0.016 0.006 0.026 1234 2015-05-19T18:58:52.814 0.030 -0.010 -0.041 1240 2015-05-20T22:58:52.814 0.013 0.003 -0.003 1245 2015-05-21T20:58:52.814 0.032 0.005 -0.016 1250 2015-05-22T18:58:52.814 -0.094 -0.004 0.063 1254 2015-05-23T11:58:52.814 0.064 -0.022 -0.078 1259 2015-05-24T09:13:52.814 0.006 -0.002 -0.006 1266 2015-05-25T16:23:52.814 -0.043 0.023 0.056 1272 2015-05-26T19:03:52.814 0.040 -0.019 -0.046 1275 2015-05-27T11:33:52.814 0.025 0.013 0.014 1278 2015-05-27T23:33:52.814 0.000 -0.000 0.000 1281 2015-05-28T13:59:59.815 -0.027 -0.013 -0.004 1288 2015-05-29T20:59:59.815 0.103 0.045 -0.002 1292 2015-05-30T14:59:59.815 -0.156 -0.078 -0.028 1297 2015-05-31T12:59:59.815 -0.169 -0.074 0.017 1302 2015-06-01T09:58:52.815 -0.371 0.041 0.291 1310 2015-06-02T19:58:52.815 -0.098 0.046 0.049 1316 2015-06-03T23:58:52.815 -0.052 0.020 0.040 1326 2015-06-05T19:58:52.815 -0.002 0.010 -0.008 1335 2015-06-07T11:28:52.815 0.115 -0.058 -0.079 1341 2015-06-08T13:58:52.815 0.295 -0.127 -0.101 1347 2015-06-09T16:58:52.815 0.380 -0.186 -0.220 1354 2015-06-10T23:58:52.815 0.212 -0.127 -0.101 1364 2015-06-12T20:58:52.815 -0.408 0.224 0.286 1391 2015-06-17T20:58:52.815 1.338 -0.640 -0.560 1394 2015-06-18T09:43:52.815 -0.536 0.227 -0.025 1402 2015-06-19T21:13:52.815 -0.024 0.003 -0.001 1405 2015-06-20T13:58:52.815 -0.447 -0.219 0.096 1413 2015-06-21T23:58:52.815 0.480 -0.021 -0.213 1416 2015-06-22T12:58:52.815 0.178 -0.035 -0.071 1421 2015-06-23T10:28:52.815 0.405 -0.189 -0.109 1427 2015-06-24T14:58:52.815 -0.426 -0.136 0.185 1433 2015-06-25T15:28:52.815 0.100 -0.036 -0.003 1440 2015-06-26T22:58:52.815 0.128 -0.050 -0.018 1444 2015-06-27T18:58:52.815 0.225 0.099 -0.095 1448 2015-06-28T11:28:52.815 -0.028 -0.005 0.005 1454 2015-06-29T13:28:52.815 0.027 -0.013 -0.003 1460 2015-06-30T18:13:52.815 -0.080 -0.038 0.033 End of comments.