MAVEN Reconstructed SPK, NAV Solution, 2019-01-01 to 2019-04-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Tue May 14 09:00:28 PDT 2019 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 8306 through 8820): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2019 JAN 01 00:01:09.183 2019 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_08264-08309_rec_v1.bsp trj_orb_08308-08348_rec_v1.bsp trj_orb_08347-08386_rec_v1.bsp trj_orb_08385-08424_rec_v1.bsp trj_orb_08423-08462_rec_v1.bsp trj_orb_08461-08500_rec_v1.bsp trj_orb_08499-08533_rec_v1.bsp trj_orb_08532-08539_rec_v1.bsp trj_orb_08538-08546_rec_v1.bsp trj_orb_08545-08552_rec_v1.bsp trj_orb_08551-08571_rec_v1.bsp trj_orb_08570-08591_rec_v1.bsp trj_orb_08591-08608_rec_v1.bsp trj_orb_08608-08620_rec_v1.bsp trj_orb_08619-08628_rec_v1.bsp trj_orb_08628-08648_rec_v1.bsp trj_orb_08647-08660_rec_v1.bsp trj_orb_08659-08672_rec_v1.bsp trj_orb_08671-08690_rec_v1.bsp trj_orb_08689-08701_rec_v1.bsp trj_orb_08701-08713_rec_v1.bsp trj_orb_08713-08728_rec_v1.bsp trj_orb_08728-08742_rec_v1.bsp trj_orb_08741-08757_rec_v1.bsp trj_orb_08756-08776_rec_v1.bsp trj_orb_08776-08789_rec_v1.bsp trj_orb_08788-08803_rec_v1.bsp trj_orb_08802-08812_rec_v1.bsp trj_orb_08811-08832_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_190101_190401_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 8308 2019-01-01T15:37:32.816 -0.009 -0.004 0.002 8312 2019-01-02T07:01:54.816 0.023 -0.011 0.009 8316 2019-01-03T01:08:36.816 -0.034 0.011 -0.008 8319 2019-01-03T15:56:50.816 0.013 0.005 -0.003 8327 2019-01-05T00:28:50.815 -0.001 0.000 -0.001 8334 2019-01-06T07:08:50.815 0.003 -0.001 0.002 8341 2019-01-07T16:03:50.815 -0.009 -0.001 0.000 8347 2019-01-08T19:28:50.815 -0.006 -0.003 0.003 8354 2019-01-10T01:58:50.815 0.022 0.009 -0.008 8359 2019-01-11T00:28:50.815 -0.013 -0.007 0.008 8369 2019-01-12T20:13:50.815 -0.000 -0.000 0.000 8376 2019-01-14T01:28:50.815 0.000 -0.000 0.000 8385 2019-01-15T16:03:50.815 0.005 -0.002 0.004 8392 2019-01-16T22:33:50.815 -0.001 0.001 -0.001 8398 2019-01-18T00:58:50.815 0.001 -0.000 0.001 8407 2019-01-19T16:58:50.815 0.001 -0.000 0.001 8415 2019-01-21T05:23:50.815 -0.012 0.001 -0.002 8423 2019-01-22T17:58:50.815 0.003 0.002 -0.002 8430 2019-01-23T23:58:50.815 -0.009 -0.002 0.001 8435 2019-01-24T21:03:50.815 0.003 -0.001 0.002 8442 2019-01-26T04:43:50.815 -0.008 -0.001 0.000 8447 2019-01-27T03:18:50.815 0.011 0.004 -0.006 8452 2019-01-27T23:43:50.815 -0.008 0.002 -0.007 8461 2019-01-29T16:15:00.815 0.012 0.001 0.002 8470 2019-01-31T05:52:45.815 -0.005 0.002 -0.008 8472 2019-01-31T16:40:46.815 0.000 0.000 -0.000 8479 2019-02-01T23:55:48.815 0.022 0.007 -0.006 8485 2019-02-03T00:15:50.815 -0.008 0.005 -0.017 8488 2019-02-03T15:45:52.815 -0.005 -0.002 0.003 8490 2019-02-04T00:21:03.815 -0.004 -0.001 0.001 8495 2019-02-04T20:30:56.897 0.016 -0.007 0.031 8499 2019-02-05T16:35:50.815 0.010 0.005 -0.013 8507 2019-02-07T02:33:50.815 0.000 0.000 0.000 8516 2019-02-08T17:28:50.815 0.003 -0.001 0.006 8521 2019-02-09T16:30:50.815 0.011 0.001 0.007 8527 2019-02-10T18:30:50.814 -0.006 0.000 -0.009 8532 2019-02-11T15:18:50.814 -0.007 0.004 -0.026 8536 2019-02-12T08:38:50.814 0.055 -0.026 0.193 8538 2019-02-12T18:58:50.814 0.079 -0.003 0.129 8542 2019-02-13T11:38:50.814 0.001 -0.001 0.005 8545 2019-02-14T00:15:25.814 0.003 -0.002 0.014 8547 2019-02-14T08:58:50.814 0.020 -0.010 0.091 8551 2019-02-15T02:58:50.814 0.037 -0.015 0.149 8557 2019-02-16T05:48:50.814 0.007 -0.001 0.019 8562 2019-02-17T01:57:50.814 -0.012 0.006 -0.067 8565 2019-02-17T15:13:50.814 0.010 -0.005 0.061 8568 2019-02-18T05:36:50.814 -0.038 -0.002 -0.111 8570 2019-02-18T13:00:09.814 -0.032 0.015 -0.230 8577 2019-02-19T18:39:32.814 0.009 -0.004 0.076 8581 2019-02-20T11:48:50.814 -0.003 0.001 -0.026 8583 2019-02-20T21:04:50.814 -0.002 0.001 -0.019 8588 2019-02-21T17:38:50.814 -0.004 0.002 -0.052 8591 2019-02-22T06:58:50.814 -0.004 0.002 -0.059 8594 2019-02-22T20:58:50.814 0.006 0.001 0.055 8600 2019-02-23T20:33:50.814 -0.005 0.002 -0.141 8604 2019-02-24T13:58:50.814 0.001 -0.000 0.028 8608 2019-02-25T06:23:50.814 -0.000 0.000 0.088 8613 2019-02-26T04:23:50.814 0.007 -0.002 -0.275 8619 2019-02-27T06:24:50.814 0.002 0.000 -0.015 8623 2019-02-27T22:34:50.814 0.002 -0.000 -0.027 8628 2019-02-28T18:21:50.814 0.003 -0.002 -0.046 8633 2019-03-01T14:43:10.814 -0.007 0.003 0.059 8639 2019-03-02T15:59:15.814 0.027 -0.011 -0.222 8645 2019-03-03T16:16:25.814 -0.023 0.010 0.137 8647 2019-03-04T00:28:04.814 -0.003 0.001 0.014 8650 2019-03-04T13:10:45.814 0.004 -0.002 -0.024 8653 2019-03-05T01:43:50.814 -0.031 0.012 0.183 8659 2019-03-06T04:20:50.814 -0.012 -0.005 -0.009 8663 2019-03-06T18:58:50.814 0.024 -0.006 -0.102 8671 2019-03-08T03:33:50.814 -0.010 0.002 0.034 8676 2019-03-08T23:43:50.814 0.022 -0.006 -0.079 8683 2019-03-10T04:18:50.814 0.035 -0.003 -0.095 8689 2019-03-11T03:14:50.814 0.022 -0.010 -0.065 8693 2019-03-11T19:28:50.814 -0.009 0.004 0.028 8694 2019-03-12T00:45:50.814 -0.026 -0.004 0.049 8701 2019-03-13T02:56:50.814 0.010 -0.004 -0.023 8704 2019-03-13T14:53:50.814 0.010 -0.005 -0.024 8707 2019-03-14T02:58:50.814 -0.025 0.010 0.064 8713 2019-03-15T02:18:50.814 0.026 -0.012 -0.055 8719 2019-03-16T01:43:50.814 -0.033 0.015 0.058 8728 2019-03-17T12:53:50.814 -0.011 0.005 0.019 8733 2019-03-18T08:23:50.814 0.018 -0.008 -0.033 8737 2019-03-18T23:48:50.814 -0.023 0.010 0.038 8741 2019-03-19T17:14:10.814 0.017 0.007 -0.014 8745 2019-03-20T06:49:41.266 -0.089 0.036 0.151 8750 2019-03-21T01:42:15.814 0.007 -0.003 -0.009 8756 2019-03-22T02:23:50.814 -0.020 -0.005 0.021 8762 2019-03-22T23:58:50.814 -0.005 0.002 0.007 8766 2019-03-23T15:13:50.814 0.047 -0.014 -0.070 8769 2019-03-24T02:28:50.814 0.008 -0.003 -0.011 8776 2019-03-25T04:22:50.814 -0.009 0.004 0.009 8777 2019-03-25T09:54:50.814 0.038 0.011 -0.036 8782 2019-03-26T05:09:50.814 0.013 0.006 -0.003 8788 2019-03-27T02:13:35.814 0.015 -0.001 -0.018 8792 2019-03-27T16:18:35.814 0.040 -0.016 -0.040 8794 2019-03-28T00:57:56.814 0.025 0.004 -0.026 8797 2019-03-28T10:32:39.814 0.005 -0.002 -0.003 8802 2019-03-29T06:56:50.814 0.087 0.030 -0.067 8806 2019-03-29T20:03:50.814 -0.128 0.048 0.116 8808 2019-03-30T04:51:50.814 0.100 0.029 -0.085 8811 2019-03-30T16:03:50.814 0.042 0.015 -0.031 8818 2019-03-31T16:43:50.814 -0.061 0.008 0.059 End of comments.