MAVEN Reconstructed SPK, NAV Solution, 2022-04-01 to 2022-07-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Tue Aug 2 09:41:41 PDT 2022 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 16098 through 16703): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2022 APR 01 00:01:09.185 2022 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_16059-16127_rec_v1.bsp trj_orb_16126-16171_rec_v1.bsp trj_orb_16170-16215_rec_v1.bsp trj_orb_16214-16263_rec_v1.bsp trj_orb_16262-16313_rec_v1.bsp trj_orb_16312-16357_rec_v1.bsp trj_orb_16356-16403_rec_v1.bsp trj_orb_16402-16448_rec_v1.bsp trj_orb_16447-16495_rec_v1.bsp trj_orb_16494-16543_rec_v1.bsp trj_orb_16542-16592_rec_v1.bsp trj_orb_16591-16635_rec_v1.bsp trj_orb_16634-16686_rec_v1.bsp trj_orb_16685-16733_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_220401_220701_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 16106 2022-04-02T07:28:50.814 -0.000 0.000 -0.001 16121 2022-04-04T15:19:20.814 -0.001 -0.000 0.002 16126 2022-04-05T07:33:50.814 -0.001 0.000 -0.003 16132 2022-04-06T05:33:50.814 -0.000 0.000 -0.000 16142 2022-04-07T18:08:50.814 -0.000 0.000 -0.000 16152 2022-04-09T05:13:50.814 0.000 -0.000 0.001 16163 2022-04-10T20:38:50.814 -0.001 0.000 -0.001 16170 2022-04-11T21:47:50.814 -0.001 0.000 -0.002 16179 2022-04-13T06:14:50.814 0.002 -0.001 0.003 16189 2022-04-14T19:58:50.814 -0.003 -0.000 0.000 16199 2022-04-16T07:28:50.814 0.003 -0.001 0.002 16206 2022-04-17T08:28:50.814 -0.003 0.001 -0.002 16214 2022-04-18T13:13:50.814 -0.002 0.001 -0.002 16225 2022-04-20T04:53:50.814 0.006 -0.002 0.005 16241 2022-04-22T15:21:50.814 -0.005 -0.000 -0.001 16246 2022-04-23T08:00:50.814 0.004 -0.001 0.003 16254 2022-04-24T13:35:50.814 0.003 -0.001 0.002 16262 2022-04-25T17:38:50.814 0.004 -0.002 0.003 16268 2022-04-26T17:28:50.814 0.002 0.001 -0.001 16274 2022-04-27T14:23:50.814 -0.004 -0.000 -0.000 16282 2022-04-28T18:35:50.814 -0.002 0.000 -0.001 16292 2022-04-30T05:33:50.814 0.000 -0.000 0.000 16302 2022-05-01T17:35:50.814 0.000 0.000 0.000 16312 2022-05-03T06:28:50.814 -0.001 0.000 -0.000 16319 2022-05-04T07:58:50.814 -0.006 0.001 -0.002 16334 2022-05-06T14:13:50.814 0.005 -0.001 0.001 16345 2022-05-08T04:43:50.814 -0.000 0.000 -0.000 16356 2022-05-09T21:53:50.814 -0.008 -0.000 -0.001 16365 2022-05-11T04:43:50.814 0.003 -0.001 0.001 16371 2022-05-12T04:08:50.814 -0.003 -0.000 -0.000 16385 2022-05-14T04:53:50.814 0.001 -0.001 0.000 16392 2022-05-15T06:18:50.814 -0.001 -0.000 -0.000 16402 2022-05-16T18:55:50.814 -0.010 0.003 -0.001 16418 2022-05-19T03:45:50.814 -0.003 0.001 -0.001 16432 2022-05-21T06:28:50.814 -0.006 0.002 -0.001 16447 2022-05-23T12:28:50.814 -0.011 0.003 -0.002 16452 2022-05-24T06:53:50.814 0.013 -0.005 0.000 16464 2022-05-26T03:28:50.814 0.026 0.004 -0.007 16478 2022-05-28T04:58:50.815 -0.003 0.002 0.001 16485 2022-05-29T06:53:50.815 -0.026 -0.000 0.008 16494 2022-05-30T13:48:50.815 0.005 -0.001 0.001 16505 2022-06-01T06:38:50.815 -0.016 0.002 0.006 16513 2022-06-02T10:58:50.815 0.006 -0.002 -0.001 16518 2022-06-03T05:44:50.815 0.005 -0.000 -0.002 16532 2022-06-05T06:58:50.815 0.000 0.000 -0.000 16542 2022-06-06T19:58:50.815 -0.004 0.000 0.002 16556 2022-06-08T21:58:50.815 0.006 -0.002 -0.002 16567 2022-06-10T14:58:50.815 -0.007 -0.002 0.005 16581 2022-06-12T17:18:50.815 0.001 -0.000 -0.001 16591 2022-06-14T03:42:50.815 -0.001 0.000 -0.000 16598 2022-06-15T04:52:50.815 -0.000 0.000 -0.000 16607 2022-06-16T13:23:50.815 -0.001 0.001 -0.001 16617 2022-06-18T02:33:50.815 0.010 -0.001 -0.009 16625 2022-06-19T06:13:50.815 -0.001 0.000 -0.000 16634 2022-06-20T14:58:50.815 -0.001 0.000 -0.000 16652 2022-06-23T07:16:50.815 -0.001 0.000 -0.002 16664 2022-06-25T03:28:50.815 0.001 -0.000 -0.000 16672 2022-06-26T08:28:50.815 0.002 -0.000 -0.002 16685 2022-06-28T06:38:50.815 -0.001 0.000 -0.001 16697 2022-06-30T02:43:50.815 0.003 -0.001 -0.004 End of comments.