MAVEN Reconstructed SPK, NAV Solution, 2023-10-01 to 2024-01-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Tue Feb 6 05:57:07 PST 2024 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 19709 through 20313): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2023 OCT 01 00:01:09.182 2024 JAN 01 01:01:09.183 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_19672-19718_rec_v1.bsp trj_orb_19717-19765_rec_v1.bsp trj_orb_19764-19819_rec_v1.bsp trj_orb_19818-19857_rec_v1.bsp trj_orb_19856-19903_rec_v1.bsp trj_orb_19902-19944_rec_v1.bsp trj_orb_19943-19964_rec_v1.bsp trj_orb_19963-20093_rec_v1.bsp trj_orb_20092-20139_rec_v1.bsp trj_orb_20138-20181_rec_v1.bsp trj_orb_20180-20228_rec_v1.bsp trj_orb_20227-20270_rec_v1.bsp trj_orb_20269-20297_rec_v1.bsp trj_orb_20296-20363_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_231001_240101_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 19717 2023-10-02T08:58:50.817 0.004 -0.002 -0.011 19732 2023-10-04T16:25:50.817 -0.011 0.003 0.080 19744 2023-10-06T12:23:50.817 0.005 -0.000 -0.026 19752 2023-10-07T17:13:50.817 0.002 -0.001 -0.011 19764 2023-10-09T13:13:50.817 -0.003 0.002 0.014 19774 2023-10-11T01:33:50.817 0.020 -0.004 -0.041 19789 2023-10-13T08:53:50.817 0.003 0.001 -0.007 19805 2023-10-15T19:03:50.817 -0.002 0.001 0.005 19818 2023-10-17T19:33:50.817 0.011 0.004 -0.023 19835 2023-10-20T08:48:50.817 -0.021 -0.002 0.035 19847 2023-10-22T03:06:50.817 -0.002 0.001 -0.002 19856 2023-10-23T11:55:50.817 -0.017 0.007 -0.017 19868 2023-10-25T08:48:50.817 0.023 -0.002 -0.020 19875 2023-10-26T10:08:50.817 -0.046 0.009 0.028 19886 2023-10-28T02:29:50.817 0.025 -0.003 -0.018 19902 2023-10-30T11:33:50.817 0.011 -0.003 0.012 19914 2023-11-01T08:48:50.817 0.005 -0.001 -0.003 19932 2023-11-04T02:28:50.817 0.028 0.001 -0.012 19943 2023-11-05T17:28:50.817 0.018 -0.008 0.013 19950 2023-11-06T18:43:50.817 -0.028 0.010 -0.027 19963 2023-11-08T19:03:50.817 -0.005 0.002 -0.001 19970 2023-11-09T19:53:50.817 -0.017 0.004 -0.013 19986 2023-11-12T08:48:50.817 -0.015 -0.006 0.010 20000 2023-11-14T08:58:50.817 -0.080 0.012 -0.035 20010 2023-11-15T21:48:50.817 0.160 -0.038 0.080 20042 2023-11-20T20:32:50.817 -0.065 -0.006 0.011 20059 2023-11-23T08:53:50.817 0.034 -0.012 0.017 20068 2023-11-24T17:03:50.817 -0.004 0.001 -0.000 20081 2023-11-26T17:23:50.817 -0.002 0.002 -0.002 20092 2023-11-28T10:13:50.816 0.029 -0.000 0.012 20101 2023-11-29T17:28:50.816 -0.017 0.005 -0.001 20111 2023-12-01T08:38:50.816 -0.048 -0.018 0.002 20127 2023-12-03T17:18:50.816 0.063 -0.015 0.034 20138 2023-12-05T09:53:50.816 0.072 0.000 0.040 20149 2023-12-07T01:43:50.816 -0.088 0.013 -0.049 20169 2023-12-10T02:33:50.816 -0.084 0.018 -0.047 20180 2023-12-11T19:27:50.816 0.028 0.005 0.020 20191 2023-12-13T09:58:50.816 -0.021 0.008 0.004 20206 2023-12-15T17:28:50.816 -0.028 0.004 -0.012 20218 2023-12-17T12:18:50.816 0.036 -0.013 -0.020 20227 2023-12-18T20:43:50.816 0.009 -0.001 -0.008 20233 2023-12-19T20:58:50.816 0.051 0.013 0.050 20247 2023-12-21T23:28:50.816 0.006 0.001 0.005 20256 2023-12-23T09:03:50.816 0.010 0.005 0.012 20269 2023-12-25T08:12:50.816 0.000 -0.002 0.000 20280 2023-12-26T23:38:50.816 -0.008 -0.000 -0.005 20291 2023-12-28T15:53:50.816 0.003 0.001 0.002 20296 2023-12-29T10:18:50.816 -0.008 -0.001 -0.007 20312 2023-12-31T19:48:50.816 0.011 -0.001 -0.002 End of comments.