Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Tue Feb 4 10:59:29 PST 2014 Objects in the Ephemeris -------------------------------------------------------- This SPK file contains ephemeris data for the Mars Reconnaissance Orbiter (MRO) spacecraft. The NAIF ID code for MRO is -74. Approximate Time Coverage -------------------------------------------------------- This file covers the following part of the Extended Science Phase of the MRO mission (orbits 33657 through 34836): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2013 OCT 01 00:01:07.182 2014 JAN 01 01:01:07.183 Status -------------------------------------------------------- This file was created by merging regular reconstructed OD solution SPK files produced by the MRO NAV team during the Extended Science 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 MRO project data base by the MRO 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 DE414 planetary ephemeris and MAR063 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: spk_psp_rec33732_33616_33732_r-v1.bsp spk_psp_rec33821_33731_33821_r-v1.bsp spk_psp_rec33912_33820_33912_r-v1.bsp spk_psp_rec33997_33911_33997_r-v1.bsp spk_psp_rec34083_33996_34083_r-v1.bsp spk_psp_rec34175_34082_34175_r-v1.bsp spk_psp_rec34266_34174_34266_r-v1.bsp spk_psp_rec34349_34265_34349_r-v1.bsp spk_psp_rec34443_34348_34443_r-v1.bsp spk_psp_rec34533_34442_34533_r-v1.bsp spk_psp_rec34608_34532_34608_r-v1.bsp spk_psp_rec34703_34607_34703_r-v1.bsp spk_psp_rec34804_34702_34804_r-v1.bsp spk_psp_rec34887_34803_34887_r-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 ./mro_psp29.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 33663 2013-10-01T14:01:52.817 0.000 0.000 0.001 33685 2013-10-03T07:08:52.817 0.000 0.000 0.001 33703 2013-10-04T16:50:52.817 -0.000 -0.000 -0.001 33719 2013-10-05T22:47:52.817 0.000 -0.000 0.000 33731 2013-10-06T20:13:52.817 -0.000 -0.000 0.001 33749 2013-10-08T06:53:52.817 0.000 -0.000 0.001 33770 2013-10-09T21:28:52.817 -0.000 -0.000 -0.000 33787 2013-10-11T05:43:52.817 -0.001 0.000 -0.003 33802 2013-10-12T09:56:52.817 0.000 0.000 0.002 33820 2013-10-13T18:43:52.817 -0.000 -0.000 0.000 33843 2013-10-15T14:28:52.817 0.000 -0.000 0.001 33860 2013-10-16T22:28:52.817 -0.000 -0.000 -0.001 33877 2013-10-18T06:16:52.817 0.000 -0.000 0.001 33896 2013-10-19T17:58:52.817 0.000 -0.000 0.001 33911 2013-10-20T20:44:52.817 0.000 -0.000 -0.001 33929 2013-10-22T07:30:52.817 0.000 0.000 0.001 33947 2013-10-23T16:57:52.817 0.000 0.000 0.001 33965 2013-10-25T02:37:52.817 0.000 -0.000 0.001 33981 2013-10-26T08:44:52.817 -0.000 0.000 -0.001 33996 2013-10-27T11:38:52.817 -0.000 -0.000 0.002 34014 2013-10-28T22:33:52.817 -0.000 -0.000 -0.001 34027 2013-10-29T22:45:52.817 -0.000 -0.000 -0.000 34045 2013-10-31T07:56:52.817 -0.000 0.000 -0.000 34063 2013-11-01T18:03:52.817 0.000 -0.000 0.001 34082 2013-11-03T04:31:52.817 0.000 0.000 -0.002 34100 2013-11-04T15:18:52.817 -0.000 0.000 -0.000 34117 2013-11-05T23:06:52.817 0.000 -0.000 0.001 34135 2013-11-07T08:45:52.817 -0.000 0.000 -0.002 34157 2013-11-09T01:53:52.817 0.001 -0.000 0.003 34174 2013-11-10T08:34:52.817 -0.000 0.000 0.002 34194 2013-11-11T21:26:52.817 0.000 -0.000 0.000 34211 2013-11-13T06:51:52.817 -0.000 0.000 -0.000 34231 2013-11-14T19:42:52.817 0.000 -0.000 -0.000 34247 2013-11-16T02:08:52.817 0.000 -0.000 0.000 34265 2013-11-17T10:45:52.817 -0.000 -0.000 0.001 34288 2013-11-19T06:48:52.817 -0.000 -0.000 -0.001 34313 2013-11-21T05:33:52.817 -0.000 -0.000 0.000 34331 2013-11-22T15:13:52.817 -0.000 0.000 -0.001 34348 2013-11-23T21:57:52.817 0.000 -0.000 -0.001 34366 2013-11-25T07:59:52.817 0.000 0.000 -0.001 34383 2013-11-26T16:28:52.817 0.000 0.000 0.000 34403 2013-11-28T05:48:52.816 0.000 -0.000 0.000 34423 2013-11-29T19:18:52.816 -0.000 -0.000 -0.003 34442 2013-12-01T05:46:52.816 -0.000 -0.000 0.002 34461 2013-12-02T18:25:52.816 -0.000 -0.000 -0.003 34480 2013-12-04T05:56:52.816 0.000 0.000 0.001 34499 2013-12-05T16:28:52.816 0.002 -0.000 0.001 34516 2013-12-07T00:28:52.816 -0.000 -0.000 0.002 34532 2013-12-08T06:06:52.816 -0.000 -0.000 0.001 34550 2013-12-09T16:15:52.816 -0.000 -0.000 0.000 34563 2013-12-10T16:43:52.816 -0.000 0.000 -0.001 34571 2013-12-11T08:09:52.816 -0.000 -0.000 -0.001 34588 2013-12-12T15:43:52.816 0.000 0.000 0.001 34607 2013-12-14T02:53:52.816 -0.000 -0.000 0.000 34627 2013-12-15T16:51:52.816 0.000 0.000 0.001 34651 2013-12-17T13:43:52.816 -0.000 0.000 -0.002 34668 2013-12-18T21:31:52.816 0.000 -0.000 0.000 34686 2013-12-20T07:13:52.816 0.000 -0.000 0.000 34702 2013-12-21T12:02:52.816 -0.000 0.000 0.000 34717 2013-12-22T16:43:52.816 -0.000 0.000 -0.000 34729 2013-12-23T15:37:52.816 0.000 -0.000 0.002 34744 2013-12-24T18:57:52.816 -0.000 0.000 0.001 34766 2013-12-26T12:48:52.816 -0.000 0.000 -0.000 34785 2013-12-28T00:21:52.816 0.000 -0.000 -0.000 34803 2013-12-29T08:56:52.816 -0.000 -0.000 0.000 34822 2013-12-30T21:27:52.816 0.000 -0.000 0.002 34836 2013-12-31T23:37:52.816 -0.000 -0.000 -0.003