Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Thu Nov 21 10:45:38 PST 2013 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 32476 through 33656): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2013 JUL 01 00:01:07.184 2013 OCT 01 01:01:07.182 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_rec32563_32468_32563_r-v1.bsp spk_psp_rec32653_32563_32653_r-v1.bsp spk_psp_rec32741_32652_32741_r-v1.bsp spk_psp_rec32810_32740_32810_r-v1.bsp spk_psp_rec32921_32809_32921_r-v1.bsp spk_psp_rec33010_32920_33010_r-v1.bsp spk_psp_rec33097_33008_33097_r-v1.bsp spk_psp_rec33187_33096_33187_r-v1.bsp spk_psp_rec33281_33185_33281_r-v1.bsp spk_psp_rec33369_33280_33369_r-v1.bsp spk_psp_rec33454_33368_33454_r-v1.bsp spk_psp_rec33545_33453_33545_r-v1.bsp spk_psp_rec33630_33544_33630_r-v1.bsp spk_psp_rec33732_33616_33732_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_psp28.bsp: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 32487 2013-07-01T22:33:52.815 -0.000 -0.000 -0.001 32505 2013-07-03T08:13:52.815 -0.000 -0.000 -0.000 32525 2013-07-04T20:58:52.815 -0.000 -0.000 0.000 32545 2013-07-06T11:02:52.816 0.000 0.000 0.000 32563 2013-07-07T19:55:52.816 -0.000 -0.000 0.000 32582 2013-07-09T08:13:52.816 0.000 -0.000 0.001 32599 2013-07-10T16:02:52.816 0.000 0.000 0.000 32616 2013-07-11T23:42:52.816 -0.000 -0.000 -0.000 32633 2013-07-13T07:37:52.816 0.001 -0.000 0.002 32652 2013-07-14T18:02:52.816 -0.000 -0.000 0.001 32673 2013-07-16T10:28:52.816 0.000 -0.000 0.001 32689 2013-07-17T16:23:52.816 -0.000 -0.000 -0.000 32702 2013-07-18T16:38:52.816 -0.000 -0.000 -0.001 32727 2013-07-20T15:22:52.816 -0.000 -0.000 -0.001 32740 2013-07-21T14:39:52.816 -0.000 0.000 0.001 32758 2013-07-23T01:25:52.816 -0.000 -0.000 -0.001 32777 2013-07-24T12:58:52.816 0.001 0.000 0.001 32790 2013-07-25T13:16:52.816 -0.001 0.000 -0.002 32809 2013-07-26T23:40:52.816 0.000 0.000 -0.001 32830 2013-07-28T16:02:52.816 -0.000 0.000 -0.000 32844 2013-07-29T18:09:52.816 -0.000 -0.000 -0.001 32858 2013-07-30T20:24:52.816 0.001 0.000 0.003 32871 2013-07-31T20:43:52.816 0.000 0.000 0.001 32886 2013-08-02T00:48:52.816 -0.000 -0.000 -0.001 32904 2013-08-03T10:27:52.816 0.000 -0.000 -0.000 32920 2013-08-04T14:57:52.816 0.001 -0.000 -0.000 32937 2013-08-06T00:20:52.816 0.001 0.000 0.002 32955 2013-08-07T09:51:52.816 -0.000 -0.000 -0.001 32972 2013-08-08T17:43:52.816 -0.001 -0.000 -0.002 32989 2013-08-10T00:58:52.816 0.001 -0.000 0.001 33008 2013-08-11T12:06:52.816 -0.000 -0.000 0.000 33020 2013-08-12T11:25:52.817 0.000 -0.000 0.001 33035 2013-08-13T15:29:52.817 -0.000 -0.000 -0.001 33051 2013-08-14T21:25:52.817 0.000 -0.000 -0.000 33074 2013-08-16T16:24:52.817 0.001 -0.000 0.002 33096 2013-08-18T08:28:52.817 0.001 0.000 -0.002 33117 2013-08-20T00:53:52.817 -0.000 0.000 -0.000 33135 2013-08-21T10:32:52.817 0.001 0.000 0.002 33148 2013-08-22T10:49:52.817 -0.000 -0.000 -0.001 33168 2013-08-24T00:08:52.817 0.000 0.000 0.000 33185 2013-08-25T06:58:52.817 -0.000 0.000 0.000 33206 2013-08-26T23:28:52.817 -0.000 0.000 -0.001 33226 2013-08-28T12:28:52.817 0.001 0.000 0.002 33245 2013-08-29T23:43:52.817 -0.000 0.000 -0.000 33263 2013-08-31T09:50:52.817 -0.000 0.000 -0.000 33280 2013-09-01T16:38:52.817 0.001 0.000 -0.002 33299 2013-09-03T05:18:52.817 -0.000 -0.000 -0.000 33317 2013-09-04T14:58:52.817 -0.000 -0.000 -0.001 33331 2013-09-05T16:58:52.817 -0.001 0.000 -0.002 33351 2013-09-07T06:31:52.817 0.000 -0.000 0.001 33368 2013-09-08T13:12:52.817 0.000 0.000 -0.001 33386 2013-09-09T23:09:52.817 -0.000 0.000 0.001 33403 2013-09-11T07:48:52.817 -0.000 0.000 -0.000 33420 2013-09-12T15:33:52.817 0.000 -0.000 0.001 33434 2013-09-13T17:44:52.817 0.000 0.000 0.000 33453 2013-09-15T04:15:52.817 0.000 -0.000 -0.001 33472 2013-09-16T16:36:52.817 -0.000 -0.000 -0.001 33486 2013-09-17T18:59:52.817 0.000 -0.000 0.002 33505 2013-09-19T06:32:52.817 -0.000 -0.000 -0.000 33523 2013-09-20T16:13:52.817 -0.000 0.000 -0.001 33544 2013-09-22T06:25:52.817 0.000 0.000 -0.000 33562 2013-09-23T16:42:52.817 -0.000 0.000 -0.000 33578 2013-09-24T23:06:52.817 0.000 -0.000 0.001 33598 2013-09-26T12:28:52.817 -0.000 -0.000 -0.001 33616 2013-09-27T21:00:52.817 -0.000 -0.000 0.001 33630 2013-09-28T23:34:52.817 -0.000 -0.000 0.001 33648 2013-09-30T09:58:52.817 0.000 -0.000 0.000