MAVEN Reconstructed SPK, NAV Solution, 2024-01-01 to 2024-04-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Sat May 4 06:43:53 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 20314 through 20912): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2024 JAN 01 00:01:09.183 2024 APR 01 01:01:09.185 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_20296-20363_rec_v1.bsp trj_orb_20362-20415_rec_v1.bsp trj_orb_20414-20460_rec_v1.bsp trj_orb_20459-20498_rec_v1.bsp trj_orb_20497-20551_rec_v1.bsp trj_orb_20550-20597_rec_v1.bsp trj_orb_20596-20641_rec_v1.bsp trj_orb_20640-20685_rec_v1.bsp trj_orb_20684-20733_rec_v1.bsp trj_orb_20732-20782_rec_v1.bsp trj_orb_20781-20828_rec_v1.bsp trj_orb_20827-20866_rec_v1.bsp trj_orb_20865-20918_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_240101_240401_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 20326 2024-01-02T21:53:50.816 -0.005 0.001 0.009 20337 2024-01-04T15:37:50.815 0.005 0.000 0.003 20349 2024-01-06T09:43:50.815 -0.003 0.000 0.005 20362 2024-01-08T11:23:50.815 0.001 0.001 0.002 20372 2024-01-09T23:33:50.815 -0.002 -0.000 -0.003 20382 2024-01-11T12:03:50.815 0.001 0.000 0.003 20390 2024-01-12T17:16:50.815 -0.009 -0.002 -0.016 20396 2024-01-13T15:37:50.815 0.006 0.002 0.023 20401 2024-01-14T09:27:50.815 0.001 0.001 -0.000 20414 2024-01-16T09:03:50.815 -0.002 -0.001 -0.009 20429 2024-01-18T15:48:50.815 0.001 0.000 0.005 20447 2024-01-21T09:30:50.815 -0.001 -0.000 -0.036 20459 2024-01-23T05:18:50.815 0.000 0.000 -0.004 20469 2024-01-24T16:11:50.815 0.000 -0.000 0.011 20483 2024-01-26T17:55:50.815 0.000 0.000 -0.002 20497 2024-01-28T20:58:50.815 -0.001 0.000 0.002 20506 2024-01-30T08:53:50.815 0.006 0.003 -0.027 20523 2024-02-01T22:53:50.815 0.001 0.000 -0.004 20537 2024-02-04T00:10:50.815 -0.001 0.000 -0.000 20550 2024-02-05T23:46:50.815 -0.015 0.001 -0.035 20557 2024-02-07T01:06:50.815 0.012 -0.002 0.026 20575 2024-02-09T17:58:50.815 0.004 -0.002 0.009 20586 2024-02-11T10:08:50.814 -0.001 0.000 -0.001 20596 2024-02-12T23:38:50.814 0.010 0.001 0.016 20612 2024-02-15T08:33:50.814 -0.011 0.004 -0.009 20625 2024-02-17T07:53:50.814 0.002 -0.001 0.001 20635 2024-02-18T20:21:50.814 -0.009 0.003 -0.004 20640 2024-02-19T14:48:50.814 -0.012 0.005 -0.011 20651 2024-02-21T07:33:50.814 -0.025 0.004 -0.031 20660 2024-02-22T16:33:50.814 -0.017 0.002 -0.021 20671 2024-02-24T07:36:50.814 -0.033 0.013 -0.008 20684 2024-02-26T07:42:50.814 -0.039 0.009 -0.037 20700 2024-02-28T17:08:50.814 -0.055 0.019 0.017 20714 2024-03-01T20:08:50.814 0.025 -0.009 -0.011 20723 2024-03-03T07:23:50.814 -0.008 -0.003 -0.005 20732 2024-03-04T14:38:50.814 0.008 -0.002 0.005 20741 2024-03-05T22:38:50.814 0.002 -0.001 -0.001 20752 2024-03-07T14:38:50.814 0.006 -0.002 -0.004 20763 2024-03-09T08:13:50.814 -0.008 -0.000 -0.005 20773 2024-03-10T20:18:50.814 0.010 -0.001 0.004 20781 2024-03-12T01:08:50.814 -0.002 0.000 -0.000 20796 2024-03-14T07:28:50.814 -0.003 0.001 0.001 20814 2024-03-17T00:58:50.814 -0.000 0.000 0.000 20819 2024-03-17T19:10:50.814 0.010 -0.004 -0.005 20827 2024-03-18T23:53:50.814 0.008 -0.003 -0.007 20833 2024-03-19T22:43:50.814 -0.001 0.000 0.000 20845 2024-03-21T19:08:50.814 0.005 0.001 0.001 20855 2024-03-23T06:33:50.814 -0.006 0.002 0.004 20865 2024-03-24T19:23:50.814 0.009 -0.002 -0.004 20870 2024-03-25T13:44:50.814 -0.016 0.002 0.006 20881 2024-03-27T06:19:50.814 -0.004 -0.001 0.000 20890 2024-03-28T14:03:50.814 -0.002 0.001 0.002 20895 2024-03-29T08:58:50.814 -0.010 0.001 0.005 20908 2024-03-31T07:05:50.814 -0.005 0.001 0.004 End of comments.