MAVEN Reconstructed SPK, NAV Solution, 2024-04-01 to 2024-07-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Thu Aug 1 07:13:55 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 20913 through 21512): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2024 APR 01 00:01:09.185 2024 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_20865-20918_rec_v1.bsp trj_orb_20917-20964_rec_v1.bsp trj_orb_20963-21009_rec_v1.bsp trj_orb_21008-21054_rec_v1.bsp trj_orb_21053-21104_rec_v1.bsp trj_orb_21103-21152_rec_v1.bsp trj_orb_21151-21195_rec_v1.bsp trj_orb_21194-21245_rec_v1.bsp trj_orb_21244-21296_rec_v1.bsp trj_orb_21295-21334_rec_v1.bsp trj_orb_21333-21385_rec_v1.bsp trj_orb_21384-21422_rec_v1.bsp trj_orb_21421-21478_rec_v1.bsp trj_orb_21477-21525_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_240401_240701_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 20917 2024-04-01T16:42:50.814 -0.029 0.007 0.028 20925 2024-04-02T21:28:50.814 0.054 -0.020 -0.065 20934 2024-04-04T06:04:50.814 -0.050 0.019 0.061 20947 2024-04-06T05:59:50.814 0.005 -0.001 -0.007 20963 2024-04-08T15:53:50.814 -0.009 0.004 0.014 20971 2024-04-09T20:43:50.814 0.006 -0.002 -0.006 20993 2024-04-13T05:44:50.814 -0.011 0.002 0.020 21008 2024-04-15T13:03:50.814 0.008 0.001 -0.013 21023 2024-04-17T20:13:50.814 -0.018 -0.006 0.022 21035 2024-04-19T14:23:50.814 -0.004 0.002 0.011 21046 2024-04-21T08:19:50.814 0.010 0.004 -0.009 21053 2024-04-22T09:33:50.814 0.003 0.001 -0.007 21070 2024-04-24T21:58:50.814 -0.002 0.001 0.007 21076 2024-04-25T20:28:50.814 -0.003 0.000 0.014 21086 2024-04-27T08:13:50.814 0.005 -0.002 -0.024 21092 2024-04-28T06:03:50.814 -0.002 0.001 0.010 21103 2024-04-29T22:53:50.814 0.007 -0.000 -0.064 21112 2024-05-01T08:43:50.814 -0.011 -0.004 0.109 21119 2024-05-02T08:41:50.814 0.007 -0.002 -0.115 21132 2024-05-04T08:33:50.814 -0.000 -0.000 -0.029 21139 2024-05-05T09:22:50.814 0.001 -0.000 0.027 21151 2024-05-07T06:51:20.814 -0.000 -0.000 -0.002 21159 2024-05-08T12:18:50.814 -0.001 -0.000 -0.002 21179 2024-05-11T12:14:14.450 0.004 0.001 0.019 21187 2024-05-12T16:22:50.814 -0.006 0.002 -0.016 21194 2024-05-13T18:58:50.814 -0.011 -0.002 -0.046 21203 2024-05-15T04:33:50.814 0.005 0.002 0.013 21210 2024-05-16T04:33:50.814 0.013 -0.002 0.029 21224 2024-05-18T08:28:50.814 -0.005 -0.002 -0.014 21231 2024-05-19T09:13:50.814 -0.000 0.000 -0.001 21244 2024-05-21T08:28:50.814 0.005 -0.001 0.007 21259 2024-05-23T15:58:50.814 0.007 0.002 0.013 21276 2024-05-26T06:03:50.814 -0.011 -0.003 -0.017 21284 2024-05-27T11:38:50.814 0.003 0.002 0.004 21295 2024-05-29T02:28:50.815 -0.002 -0.000 -0.002 21310 2024-05-31T09:23:50.815 0.010 0.001 0.009 21316 2024-06-01T06:56:50.815 -0.012 0.001 -0.008 21323 2024-06-02T08:27:50.815 0.007 -0.001 0.004 21333 2024-06-03T20:58:50.815 -0.012 -0.000 -0.007 21344 2024-06-05T13:30:50.815 0.009 0.002 0.007 21351 2024-06-06T14:53:50.815 -0.009 -0.001 -0.006 21363 2024-06-08T08:58:50.815 -0.000 -0.000 -0.000 21375 2024-06-10T05:28:50.815 0.006 -0.001 0.000 21384 2024-06-11T14:18:50.815 0.012 -0.003 0.001 21390 2024-06-12T12:33:50.815 -0.007 -0.000 -0.002 21402 2024-06-14T09:22:50.815 -0.013 -0.005 -0.008 21409 2024-06-15T08:52:50.815 0.014 -0.005 -0.004 21421 2024-06-17T04:11:50.815 -0.007 0.003 0.003 21428 2024-06-18T06:02:50.815 0.015 -0.006 -0.004 21437 2024-06-19T14:09:50.815 -0.003 0.001 0.001 21447 2024-06-21T03:16:50.815 -0.001 0.000 0.000 21455 2024-06-22T07:53:50.815 -0.010 0.003 0.003 21465 2024-06-23T21:10:50.815 0.018 -0.005 -0.001 21477 2024-06-25T16:28:50.815 0.022 -0.009 -0.003 21483 2024-06-26T14:58:50.815 -0.019 0.003 0.001 21498 2024-06-28T20:58:50.815 0.003 -0.001 -0.000 21506 2024-06-30T03:01:50.815 -0.005 -0.000 0.000 End of comments.