MAVEN Reconstructed SPK, NAV Solution, 2015-01-01 to 2015-04-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Wed May 20 10:10:26 PDT 2015 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 498 through 972): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2015 JAN 01 00:01:07.183 2015 APR 01 01:01:07.185 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_00482-00523_rec_v1.bsp trj_orb_00522-00544_rec_v1.bsp trj_orb_00543-00595_rec_v1.bsp trj_orb_00592-00637_rec_v1.bsp trj_orb_00636-00665_rec_v1.bsp trj_orb_00664-00713_rec_v1.bsp trj_orb_00708-00718_rec_v1.bsp trj_orb_00718-00724_rec_v1.bsp trj_orb_00723-00728_rec_v1.bsp trj_orb_00728-00733_rec_v1.bsp trj_orb_00733-00739_rec_v1.bsp trj_orb_00739-00744_rec_v1.bsp trj_orb_00744-00750_rec_v1.bsp trj_orb_00750-00785_rec_v1.bsp trj_orb_00784-00822_rec_v1.bsp trj_orb_00811-00853_rec_v1.bsp trj_orb_00852-00897_rec_v1.bsp trj_orb_00896-00907_rec_v1.bsp trj_orb_00906-00971_rec_v1.bsp trj_orb_00970-00991_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_150101_150401_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 501 2015-01-01T18:58:52.816 -0.008 0.002 -0.053 507 2015-01-03T00:28:52.816 0.005 0.003 0.048 517 2015-01-04T18:58:52.815 0.004 -0.004 -0.017 522 2015-01-05T19:28:52.815 0.011 -0.001 0.046 528 2015-01-07T00:28:52.815 -0.051 -0.028 -0.282 532 2015-01-07T18:38:52.815 0.088 0.045 0.451 537 2015-01-08T16:58:52.815 0.051 0.017 0.210 543 2015-01-09T18:28:52.815 -0.105 0.053 0.033 548 2015-01-10T19:03:52.815 -0.201 -0.046 -0.606 551 2015-01-11T08:58:52.815 0.127 0.040 0.402 558 2015-01-12T16:58:52.815 -0.139 -0.043 -0.386 564 2015-01-13T18:59:59.815 0.242 -0.087 0.124 568 2015-01-14T13:58:52.815 -0.188 0.008 -0.276 569 2015-01-14T18:58:52.815 0.057 0.009 0.110 574 2015-01-15T19:18:52.815 0.034 0.017 0.084 581 2015-01-17T00:59:59.815 -0.004 0.001 -0.002 585 2015-01-17T18:59:59.815 -0.020 0.008 0.002 590 2015-01-18T19:14:59.815 -0.056 -0.012 -0.085 592 2015-01-19T03:59:59.815 0.087 0.002 0.089 600 2015-01-20T18:19:59.815 0.046 0.023 0.095 606 2015-01-21T19:03:52.815 -0.032 0.014 0.014 611 2015-01-22T18:48:52.815 0.082 -0.006 0.044 618 2015-01-24T01:58:52.815 -0.121 0.054 0.068 621 2015-01-24T17:58:52.815 -0.065 -0.033 -0.111 627 2015-01-25T18:58:52.815 0.122 -0.060 -0.109 630 2015-01-26T09:58:52.815 0.122 0.003 0.052 636 2015-01-27T14:03:52.815 0.007 0.003 0.006 642 2015-01-28T17:58:52.815 0.064 0.030 0.082 645 2015-01-29T08:38:52.815 -0.000 0.000 -0.000 647 2015-01-29T17:48:52.815 0.000 -0.000 -0.000 654 2015-01-30T23:59:59.815 0.018 0.002 0.005 657 2015-01-31T15:29:59.815 0.034 0.013 0.044 664 2015-02-01T20:59:59.815 -0.037 0.011 0.017 668 2015-02-02T18:14:59.815 -0.007 0.000 -0.000 673 2015-02-03T16:28:52.815 -0.017 -0.009 -0.022 680 2015-02-04T23:18:52.815 -0.024 -0.004 -0.004 684 2015-02-05T18:03:52.815 0.019 0.007 0.008 691 2015-02-07T01:53:52.815 0.016 0.005 0.002 695 2015-02-07T19:18:52.815 -0.021 0.004 0.009 700 2015-02-08T19:18:52.815 -0.018 -0.006 -0.004 703 2015-02-09T09:43:52.815 0.000 0.000 0.000 708 2015-02-10T06:28:52.814 0.032 -0.011 -0.023 711 2015-02-10T21:29:59.814 -0.045 -0.012 0.001 713 2015-02-11T07:14:59.814 -0.162 -0.079 -0.068 715 2015-02-11T14:29:59.814 0.050 -0.018 -0.037 718 2015-02-12T05:13:52.814 0.089 0.014 -0.020 721 2015-02-12T20:23:52.814 0.128 0.061 0.126 722 2015-02-12T21:28:52.814 -0.007 0.004 0.008 723 2015-02-13T03:59:59.814 -0.571 -0.077 0.155 726 2015-02-13T18:39:59.814 -0.280 -0.145 -0.125 728 2015-02-14T00:58:52.814 0.006 0.000 -0.002 731 2015-02-14T15:58:52.814 0.012 -0.002 -0.010 733 2015-02-14T23:58:52.814 -0.181 0.091 0.185 735 2015-02-15T11:28:52.814 0.244 0.124 0.081 737 2015-02-15T19:28:52.814 -1.051 -0.117 0.407 739 2015-02-16T03:33:52.814 0.024 -0.008 -0.020 742 2015-02-16T19:03:52.814 -0.010 -0.005 -0.002 744 2015-02-17T01:33:52.814 -0.256 0.133 0.268 747 2015-02-17T16:28:52.814 -0.236 -0.015 0.117 749 2015-02-18T00:59:59.814 0.246 -0.041 -0.171 750 2015-02-18T04:35:42.814 0.048 -0.024 -0.047 752 2015-02-18T16:06:37.814 0.038 0.020 0.007 758 2015-02-19T18:08:52.814 -0.071 -0.008 0.036 765 2015-02-21T02:53:52.814 -0.040 -0.020 -0.010 769 2015-02-21T19:18:52.814 -0.000 0.001 0.000 774 2015-02-22T19:18:52.814 -0.003 -0.002 0.001 779 2015-02-23T17:59:59.814 0.020 0.011 0.001 784 2015-02-24T13:59:59.814 -0.001 -0.000 0.000 788 2015-02-25T09:29:59.814 0.051 0.008 -0.033 793 2015-02-26T09:14:59.814 -0.067 -0.035 -0.011 795 2015-02-26T18:39:59.814 0.032 0.011 0.026 802 2015-02-28T01:58:52.814 0.024 0.011 0.009 810 2015-03-01T13:58:52.814 -0.014 -0.006 -0.002 811 2015-03-01T16:48:52.814 0.058 0.001 -0.050 817 2015-03-02T19:01:52.814 -0.002 0.001 0.002 822 2015-03-03T19:01:52.814 -0.019 -0.006 0.015 827 2015-03-04T18:13:52.814 0.030 0.016 -0.015 833 2015-03-05T19:03:52.814 -0.011 0.005 0.010 840 2015-03-07T02:43:52.814 -0.210 0.081 0.200 843 2015-03-07T18:28:52.814 0.126 0.065 -0.068 848 2015-03-08T16:38:52.814 0.002 0.001 -0.002 852 2015-03-09T09:43:52.814 -0.181 -0.004 0.187 859 2015-03-10T17:43:52.814 -0.088 -0.025 0.095 864 2015-03-11T15:14:59.814 -0.117 0.029 0.118 870 2015-03-12T18:59:59.814 0.186 0.018 -0.205 877 2015-03-14T01:59:59.814 0.042 -0.006 -0.045 880 2015-03-14T17:18:52.814 -0.029 -0.015 0.025 885 2015-03-15T14:18:52.814 -0.936 0.043 1.053 886 2015-03-15T19:18:52.814 0.730 0.139 -0.883 891 2015-03-16T19:18:52.814 -0.004 -0.004 0.002 896 2015-03-17T16:29:59.814 0.036 0.007 -0.047 902 2015-03-18T19:29:59.814 -0.059 -0.009 0.076 906 2015-03-19T12:59:59.814 -0.043 0.006 0.049 913 2015-03-20T20:59:59.814 0.010 0.001 -0.013 917 2015-03-21T14:58:52.814 0.227 0.008 -0.289 922 2015-03-22T13:13:52.814 -0.053 0.007 0.062 927 2015-03-23T11:38:52.814 0.105 -0.021 -0.113 933 2015-03-24T14:58:52.814 0.014 -0.001 -0.018 938 2015-03-25T13:58:52.814 0.170 0.022 -0.249 942 2015-03-26T07:48:52.814 0.118 0.003 -0.160 943 2015-03-26T12:58:52.814 -0.014 -0.004 0.023 951 2015-03-27T22:28:52.814 -0.032 0.012 -0.054 954 2015-03-28T13:58:52.814 -0.032 -0.000 0.045 962 2015-03-30T01:14:52.814 0.013 -0.005 -0.008 970 2015-03-31T13:13:52.814 -0.031 0.014 0.008 End of comments.