MAVEN Reconstructed SPK, NAV Solution, 2015-10-01 to 2016-01-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Wed Feb 3 10:57:10 PST 2016 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 1954 through 2440): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2015 OCT 01 00:01:08.182 2016 JAN 01 01:01:08.183 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_01942-01983_rec_v1.bsp trj_orb_01982-02015_rec_v1.bsp trj_orb_02014-02058_rec_v1.bsp trj_orb_02057-02068_rec_v1.bsp trj_orb_02067-02125_rec_v1.bsp trj_orb_02124-02168_rec_v1.bsp trj_orb_02167-02206_rec_v1.bsp trj_orb_02205-02238_rec_v1.bsp trj_orb_02237-02279_rec_v1.bsp trj_orb_02278-02316_rec_v1.bsp trj_orb_02315-02353_rec_v1.bsp trj_orb_02352-02391_rec_v1.bsp trj_orb_02390-02428_rec_v1.bsp trj_orb_02427-02459_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_151001_160101_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 1957 2015-10-01T15:58:51.817 0.010 -0.005 -0.002 1962 2015-10-02T14:28:51.817 -0.030 0.014 -0.017 1968 2015-10-03T17:43:51.817 0.006 -0.003 0.005 1971 2015-10-04T08:28:51.817 -0.031 0.010 0.038 1974 2015-10-04T20:58:51.817 -0.000 0.000 -0.000 1976 2015-10-05T06:28:51.817 0.038 -0.020 -0.009 1982 2015-10-06T12:28:51.817 0.005 0.002 -0.008 1989 2015-10-07T19:38:51.817 0.011 0.003 -0.017 1993 2015-10-08T13:58:51.817 0.010 0.004 -0.015 2000 2015-10-09T20:58:51.817 0.034 -0.002 -0.039 2007 2015-10-11T04:58:51.817 -0.028 -0.001 0.031 2014 2015-10-12T11:58:51.817 0.032 -0.011 -0.023 2020 2015-10-13T15:58:51.817 0.016 0.000 -0.015 2023 2015-10-14T04:58:51.817 0.007 -0.002 -0.005 2026 2015-10-14T19:28:51.817 0.002 0.000 -0.002 2031 2015-10-15T19:18:51.817 -0.008 -0.004 0.009 2037 2015-10-16T19:58:51.817 0.015 -0.007 -0.002 2041 2015-10-17T15:28:51.817 -0.049 -0.001 0.040 2044 2015-10-18T04:58:51.817 0.002 -0.000 -0.001 2048 2015-10-18T22:28:51.817 0.014 -0.005 -0.007 2051 2015-10-19T11:58:51.817 0.008 -0.004 -0.003 2057 2015-10-20T15:38:51.817 -0.010 0.002 0.005 2063 2015-10-21T19:08:51.817 0.039 -0.005 -0.022 2067 2015-10-22T12:03:51.817 0.046 -0.024 0.008 2074 2015-10-23T19:28:51.817 -0.007 0.003 -0.004 2078 2015-10-24T15:58:51.817 -0.076 -0.015 0.050 2084 2015-10-25T17:28:51.817 0.037 -0.019 0.000 2087 2015-10-26T06:58:51.817 -0.019 0.010 -0.002 2093 2015-10-27T11:58:51.817 0.002 0.000 -0.001 2097 2015-10-28T04:28:51.817 -0.007 0.004 -0.000 2105 2015-10-29T16:28:51.817 0.022 -0.010 0.008 2111 2015-10-30T19:58:51.817 -0.031 0.016 -0.004 2113 2015-10-31T07:58:51.817 -0.003 -0.002 0.002 2120 2015-11-01T12:58:51.817 0.010 -0.006 0.001 2124 2015-11-02T08:58:51.817 0.020 0.004 -0.009 2130 2015-11-03T12:58:51.817 0.048 0.024 -0.023 2135 2015-11-04T11:28:51.817 -0.031 -0.013 0.014 2141 2015-11-05T11:58:51.817 -0.011 0.005 -0.003 2148 2015-11-06T20:58:51.817 -0.024 0.007 0.005 2156 2015-11-08T09:13:51.817 0.029 -0.009 -0.005 2158 2015-11-08T18:58:51.817 -0.046 0.000 0.012 2161 2015-11-09T07:58:51.817 0.027 -0.009 -0.005 2167 2015-11-10T11:58:51.817 -0.004 -0.001 0.001 2172 2015-11-11T11:58:51.817 -0.029 -0.015 0.008 2176 2015-11-12T04:28:51.817 0.030 -0.004 -0.006 2183 2015-11-13T12:08:51.817 0.036 -0.007 -0.007 2187 2015-11-14T05:28:51.817 -0.043 0.023 0.004 2193 2015-11-15T10:58:51.817 0.036 0.017 -0.007 2195 2015-11-15T18:28:51.817 -0.059 0.016 0.010 2199 2015-11-16T11:58:51.817 0.002 -0.001 -0.000 2205 2015-11-17T14:58:51.817 -0.048 0.025 0.004 2208 2015-11-18T05:58:51.817 -0.096 -0.001 0.016 2215 2015-11-19T11:58:51.817 0.034 -0.016 -0.001 2221 2015-11-20T15:13:51.817 -0.020 0.010 0.001 2224 2015-11-21T04:43:51.817 -0.014 0.006 0.000 2232 2015-11-22T17:43:51.817 0.046 -0.020 -0.008 2237 2015-11-23T15:48:51.817 0.020 -0.011 -0.003 2242 2015-11-24T14:58:51.817 -0.058 0.028 0.011 2245 2015-11-25T05:58:51.817 0.051 0.006 -0.006 2252 2015-11-26T13:58:51.817 -0.028 -0.006 0.003 2262 2015-11-28T11:23:51.816 0.039 0.011 -0.003 2266 2015-11-29T04:58:51.816 -0.075 -0.001 0.010 2271 2015-11-30T03:58:51.816 0.031 0.005 -0.003 2278 2015-12-01T11:58:51.816 -0.031 -0.009 0.001 2285 2015-12-02T18:28:51.816 -0.011 0.003 0.003 2287 2015-12-03T03:58:51.816 0.006 -0.000 -0.001 2294 2015-12-04T11:18:51.816 0.011 -0.003 -0.003 2303 2015-12-06T03:48:51.816 -0.007 0.003 0.002 2310 2015-12-07T11:13:51.816 0.015 -0.007 -0.006 2315 2015-12-08T10:58:51.816 0.033 -0.001 -0.006 2323 2015-12-09T21:43:51.816 -0.021 0.011 0.011 2332 2015-12-11T14:28:51.816 0.012 -0.007 -0.007 2342 2015-12-13T11:13:51.816 -0.005 0.001 0.001 2345 2015-12-14T03:58:51.816 0.024 0.011 0.005 2352 2015-12-15T10:58:51.816 0.003 0.000 -0.000 2358 2015-12-16T12:28:51.816 -0.002 0.001 0.001 2361 2015-12-17T03:48:51.816 0.010 0.002 -0.001 2369 2015-12-18T16:48:51.816 -0.013 -0.006 -0.004 2372 2015-12-19T03:58:51.816 0.010 -0.005 -0.007 2377 2015-12-20T03:33:51.816 0.014 -0.001 -0.005 2382 2015-12-21T03:34:51.816 -0.023 -0.011 -0.007 2390 2015-12-22T12:58:51.816 -0.002 0.001 0.002 2394 2015-12-23T06:58:51.816 -0.010 0.005 0.009 2396 2015-12-23T16:28:51.816 0.007 -0.004 -0.006 2401 2015-12-24T14:28:51.816 -0.002 0.001 0.002 2409 2015-12-26T03:28:51.816 -0.005 0.002 0.004 2415 2015-12-27T05:48:51.816 -0.004 0.001 0.003 2417 2015-12-27T16:18:51.816 -0.005 0.001 0.003 2422 2015-12-28T14:28:51.816 0.026 -0.009 -0.023 2427 2015-12-29T12:58:51.816 0.068 -0.027 -0.068 2430 2015-12-30T03:28:51.816 -0.053 -0.002 0.026 2433 2015-12-30T16:28:51.816 -0.020 0.005 0.017 2437 2015-12-31T10:58:51.816 0.050 -0.001 -0.029 End of comments.