MAVEN Reconstructed SPK, NAV Solution, 2024-07-01 to 2024-10-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Tue Oct 29 06:06:04 PDT 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 21513 through 22116): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2024 JUL 01 00:01:09.184 2024 OCT 01 01:01:09.182 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_21477-21525_rec_v1.bsp trj_orb_21524-21568_rec_v1.bsp trj_orb_21567-21608_rec_v1.bsp trj_orb_21607-21661_rec_v1.bsp trj_orb_21660-21701_rec_v1.bsp trj_orb_21700-21749_rec_v1.bsp trj_orb_21748-21799_rec_v1.bsp trj_orb_21798-21844_rec_v1.bsp trj_orb_21843-21885_rec_v1.bsp trj_orb_21884-21931_rec_v1.bsp trj_orb_21930-21980_rec_v1.bsp trj_orb_21979-22024_rec_v1.bsp trj_orb_22023-22072_rec_v1.bsp trj_orb_22071-22115_rec_v1.bsp trj_orb_22114-22165_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_240701_241001_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 21515 2024-07-01T10:48:50.815 -0.026 0.010 0.001 21524 2024-07-02T21:20:50.815 -0.002 -0.005 0.000 21535 2024-07-04T11:13:50.815 0.002 -0.001 0.000 21546 2024-07-06T03:18:50.816 0.036 -0.013 0.004 21555 2024-07-07T14:18:50.816 0.029 0.011 -0.003 21567 2024-07-09T08:33:50.816 0.046 -0.013 0.005 21582 2024-07-11T16:28:50.816 -0.002 -0.001 0.000 21593 2024-07-13T07:28:50.816 -0.009 0.002 -0.001 21601 2024-07-14T11:36:50.816 0.015 -0.005 0.005 21607 2024-07-15T10:43:50.816 0.004 0.000 0.000 21619 2024-07-17T06:28:50.816 0.004 0.000 0.000 21633 2024-07-19T08:38:50.816 -0.011 0.004 -0.005 21646 2024-07-21T07:28:50.816 0.007 -0.003 0.004 21660 2024-07-23T10:13:50.816 0.002 -0.000 0.001 21673 2024-07-25T09:52:50.816 0.001 0.000 0.000 21686 2024-07-27T09:13:50.816 -0.003 0.001 -0.002 21700 2024-07-29T13:48:50.816 0.008 0.002 0.001 21708 2024-07-30T18:35:50.816 -0.007 -0.001 -0.003 21720 2024-08-01T13:00:50.816 0.002 -0.001 0.002 21728 2024-08-02T18:35:50.816 -0.009 0.003 -0.009 21738 2024-08-04T06:30:50.816 0.006 -0.002 0.007 21748 2024-08-05T21:05:50.816 0.001 0.000 -0.000 21763 2024-08-08T02:33:50.816 0.005 -0.000 0.005 21773 2024-08-09T13:43:50.816 -0.005 0.002 -0.006 21784 2024-08-11T06:33:50.816 0.003 -0.001 0.004 21798 2024-08-13T09:43:50.817 -0.002 0.000 -0.003 21810 2024-08-15T04:28:50.817 0.003 -0.001 0.006 21818 2024-08-16T09:48:50.817 -0.001 0.001 -0.003 21833 2024-08-18T17:18:50.817 -0.003 0.000 -0.008 21840 2024-08-19T18:53:50.817 0.008 0.000 0.021 21843 2024-08-20T05:09:50.817 0.005 -0.002 0.017 21850 2024-08-21T07:09:50.817 -0.001 0.000 -0.004 21865 2024-08-23T13:23:50.817 0.002 -0.001 0.007 21876 2024-08-25T05:48:50.817 -0.001 0.000 -0.003 21884 2024-08-26T11:53:50.817 -0.005 0.001 -0.033 21895 2024-08-28T04:08:50.817 0.009 -0.002 0.087 21902 2024-08-29T06:43:50.817 -0.008 -0.002 -0.087 21916 2024-08-31T08:34:50.817 0.002 -0.001 0.060 21930 2024-09-02T12:38:50.817 -0.001 -0.000 0.028 21943 2024-09-04T11:45:50.817 -0.003 0.000 0.025 21950 2024-09-05T13:28:50.817 -0.003 0.001 0.021 21960 2024-09-07T02:13:50.817 0.016 -0.006 -0.094 21968 2024-09-08T07:24:50.817 0.000 0.000 -0.000 21979 2024-09-10T01:03:50.817 0.002 0.000 -0.008 21986 2024-09-11T01:48:50.817 0.000 -0.000 -0.001 21995 2024-09-12T12:18:50.817 0.001 0.000 -0.002 22005 2024-09-14T01:08:50.817 0.012 0.005 -0.021 22014 2024-09-15T08:38:50.817 0.007 -0.002 -0.019 22023 2024-09-16T17:58:50.817 0.014 -0.001 -0.036 22033 2024-09-18T06:18:50.817 0.017 -0.004 -0.036 22041 2024-09-19T11:38:50.817 -0.057 0.013 0.110 22053 2024-09-21T08:18:50.817 0.026 0.003 -0.048 22059 2024-09-22T05:28:50.817 -0.043 0.012 0.063 22071 2024-09-24T02:03:50.817 -0.065 0.000 0.103 22080 2024-09-25T10:43:50.817 0.053 -0.008 -0.072 22094 2024-09-27T14:28:50.817 -0.030 -0.002 0.041 22104 2024-09-29T02:35:50.817 0.005 -0.001 -0.005 22114 2024-09-30T15:18:50.817 0.006 -0.001 -0.006 End of comments.