Mars Reconnaissance Orbiter Extended Science Phase SPK, MRO NAV Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, Fri Feb 18 15:29:52 PST 2011 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 19591 through 20771): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2010 OCT 01 00:01:06.182 2011 JAN 01 01:01:06.183 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_rec19614_19526_19614_r-v1.bsp spk_psp_rec19705_19613_19705_r-v1.bsp spk_psp_rec19787_19703_19787_r-v1.bsp spk_psp_rec19898_19785_19898_r-v1.bsp spk_psp_rec19984_19897_19984_r-v1.bsp spk_psp_rec20075_19982_20075_r-v1.bsp spk_psp_rec20157_20073_20157_r-v1.bsp spk_psp_rec20254_20155_20254_r-v1.bsp spk_psp_rec20329_20252_20329_r-v1.bsp spk_psp_rec20420_20329_20420_r-v1.bsp spk_psp_rec20527_20418_20527_r-v1.bsp spk_psp_rec20617_20525_20617_r-v1.bsp spk_psp_rec20706_20615_20706_r-v1.bsp spk_psp_rec20796_20705_20796_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_psp17.bsp: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 19594 2010-10-01T07:23:53.817 -0.001 0.000 -0.001 19613 2010-10-02T17:53:53.817 -0.004 0.000 0.002 19631 2010-10-04T04:48:53.817 0.000 0.000 0.000 19653 2010-10-05T20:14:53.817 -0.001 -0.000 -0.000 19667 2010-10-06T22:25:53.817 0.004 0.000 0.001 19676 2010-10-07T15:14:53.817 -0.003 0.000 -0.001 19691 2010-10-08T20:28:53.817 -0.003 -0.000 -0.000 19703 2010-10-09T17:59:53.817 0.002 0.000 -0.000 19721 2010-10-11T03:22:53.817 0.004 0.000 0.001 19741 2010-10-12T16:47:53.817 -0.001 0.000 -0.000 19758 2010-10-14T00:51:53.817 -0.005 -0.000 0.001 19772 2010-10-15T03:01:53.817 -0.006 -0.000 0.001 19785 2010-10-16T03:38:53.817 0.004 -0.000 -0.002 19804 2010-10-17T16:18:53.817 0.001 0.000 0.000 19821 2010-10-19T00:08:53.817 -0.000 -0.000 -0.000 19841 2010-10-20T13:33:53.817 -0.001 -0.000 -0.000 19859 2010-10-21T21:24:53.817 0.006 0.000 0.001 19876 2010-10-23T06:39:53.817 0.002 -0.000 0.001 19897 2010-10-24T20:48:53.817 -0.003 -0.000 0.001 19913 2010-10-26T02:43:53.817 -0.002 0.000 0.000 19929 2010-10-27T09:33:53.817 -0.000 -0.000 -0.000 19952 2010-10-29T03:19:35.817 0.000 0.000 0.000 19966 2010-10-30T05:29:53.817 -0.001 0.000 -0.000 19982 2010-10-31T12:08:53.817 -0.003 0.000 0.001 20001 2010-11-01T22:58:53.817 -0.004 0.000 -0.000 20018 2010-11-03T07:58:53.817 0.002 0.000 0.001 20037 2010-11-04T19:53:53.817 -0.000 -0.000 -0.000 20056 2010-11-06T07:13:53.817 -0.001 0.000 -0.000 20073 2010-11-07T14:08:53.817 -0.000 0.000 0.000 20090 2010-11-08T23:08:53.817 0.001 0.000 0.000 20108 2010-11-10T08:50:53.817 -0.003 -0.000 -0.001 20124 2010-11-11T14:45:53.817 0.001 -0.000 0.000 20142 2010-11-13T00:24:53.817 0.002 0.000 0.000 20155 2010-11-14T00:19:53.817 -0.005 0.000 -0.002 20177 2010-11-15T16:17:53.817 -0.004 -0.000 0.001 20194 2010-11-17T00:20:53.817 -0.005 0.000 0.002 20213 2010-11-18T13:11:53.817 0.006 0.000 0.001 20232 2010-11-20T00:23:53.817 -0.006 -0.000 -0.003 20252 2010-11-21T12:46:53.817 0.002 -0.000 -0.001 20273 2010-11-23T04:52:53.817 0.005 -0.000 0.002 20292 2010-11-24T15:20:53.817 -0.002 -0.000 0.001 20310 2010-11-26T02:33:53.817 -0.001 0.000 -0.000 20329 2010-11-27T12:59:53.817 -0.001 0.000 0.000 20348 2010-11-29T00:02:53.816 -0.001 -0.000 0.001 20365 2010-11-30T09:18:53.816 -0.001 0.000 -0.000 20378 2010-12-01T08:53:53.816 0.000 0.000 0.000 20399 2010-12-03T00:08:53.816 -0.000 0.000 0.000 20418 2010-12-04T11:33:53.816 -0.001 0.000 0.000 20441 2010-12-06T07:28:53.816 0.001 -0.000 0.000 20454 2010-12-07T07:43:53.816 0.002 0.000 0.001 20474 2010-12-08T21:11:53.816 0.002 0.000 0.001 20489 2010-12-10T00:48:53.816 -0.000 0.000 -0.000 20509 2010-12-11T13:04:53.816 0.004 -0.000 -0.001 20525 2010-12-12T19:03:53.816 -0.003 -0.000 0.001 20544 2010-12-14T08:13:53.816 0.001 -0.000 -0.000 20565 2010-12-15T23:20:53.816 0.002 -0.000 0.000 20583 2010-12-17T08:58:53.816 -0.004 0.000 -0.001 20603 2010-12-18T22:28:53.816 -0.002 0.000 -0.000 20615 2010-12-19T19:28:53.816 -0.002 0.000 0.001 20631 2010-12-21T02:38:53.816 -0.004 -0.000 -0.002 20650 2010-12-22T14:13:53.816 -0.001 -0.000 -0.000 20668 2010-12-23T23:53:53.816 0.003 0.000 0.001 20691 2010-12-25T18:43:53.816 0.003 -0.000 0.002 20705 2010-12-26T19:38:53.816 -0.004 -0.000 0.002 20723 2010-12-28T06:58:53.816 0.001 -0.000 0.000 20740 2010-12-29T14:43:53.816 -0.006 0.000 -0.000 20758 2010-12-31T00:18:53.816 -0.002 0.000 -0.000