CODES Asteroid Ephemeris SPK File =========================================================================== Created by Boris Semenov, NAIF/JPL, July 29, 2010 Objects in the Ephemeris -------------------------------------------------------- This file contains ephemeris data for 300 asteroids. These ephemerides were integrated by the Comet/asteroid Orbit Determination and Ephemeris Software (CODES) developed by Jim Baer and available from http://home.earthlink.net/~jimbaer1/ The SPICE utility program BRIEF can be used to get the complete list of asteroids, the data for which is stored in this file. The center of motion for all asteroids is the Sun (NAIF ID 10) and the reference frame is ``ECLIPJ2000_DE405'' (frame ID 1900017), defined in a special frames kernel, a copy of which is provided in Appendix 1. Approximate Time Coverage -------------------------------------------------------- The data for each of the asteroids covers the following time span: COVERAGE BEGIN TIME (TDB): 1799 DEC 30 12:00:00.000 COVERAGE END TIME (TDB): 2199 DEC 13 12:00:00.000 Pedigree -------------------------------------------------------- This file was generated by ``packaging'' classical orbital elements generated by the CODES software into SPK format using NAIF's MKSPK program. The description of the CODES output file and the contents of the accompanying ``mu.txt'' file are provided in Appendix 3. The data for each of the asteroids was extracted from the CODES data file and packaged into a type 13 SPK segment with interpolation degree set to 15. The Sun GM values used by MKSPK to convert orbital elements into states stored in the SPK file was 132712440017.987, the value used in JPL's DE405 planet ephemerides. Example MKSPK input and setup files used for MKSPK runs are provided in Appendix 2. Usage -------------------------------------------------------- This file should be used together with the DE405 planetary ephemeris since the integration was done using the DE405 ephemeris and with the frames kernel defining the ``ECLIPJ2000_DE405'' frame. Contacts -------------------------------------------------------- If you have any questions regarding this data contact Boris V. Semenov, NAIF/JPL, Boris.Semenov@jpl.nasa.gov or Jim Baer jimbaer1@earthlink.net Appendix 1: Frames Kernel (FK) defining ``ECLIPJ2000_DE405'' =========================================================================== SPICE Frames Kernel (FK) file defining the ``ECLIPJ2000_DE405'' must be used together with this SPK file. This FK must have the following contents: ----------------- KPL/FK This frames kernel defines the Ecliptic and Equinox of the J2000 frame using the DE405 obliquity angle value (84381.412 arcseconds). This frame is used as the reference frame in the SPK file containing asteroid ephemeris data generated by the Comet/asteroid Orbit Determination and Ephemeris Software (CODES) developed by Jim Baer. The frame ID for this frame is set to 1900017, an arbitrarily chosen number from the range 1400000 to 2000000 set aside by NAIF for public use (see frames.req document). Contact Boris Semenov, NAIF (Boris.Semenov@jpl.nasa.gov) or Jim Baer (jimbaer1@earthlink.net) if you have any question about this kernel. \begindata FRAME_ECLIPJ2000_DE405 = 1900017 FRAME_1900017_NAME = 'ECLIPJ2000_DE405' FRAME_1900017_CLASS = 4 FRAME_1900017_CLASS_ID = 1900017 FRAME_1900017_CENTER = 0 TKFRAME_1900017_SPEC = 'ANGLES' TKFRAME_1900017_RELATIVE = 'J2000' TKFRAME_1900017_ANGLES = ( 0.0, 0.0, -84381.412 ) TKFRAME_1900017_AXES = ( 1, 3, 1 ) TKFRAME_1900017_UNITS = 'ARCSECONDS' \begintext ----------------- Appendix 2: MKSPK Setup =========================================================================== These are example MKSPK setup and input files used in the MKSPK run that produced the segment for asteroid 511. A similar setup files was used for each of the other asteroids, but with revisions to the OBJECT_ID and SEGMENT_ID keywords MKSPK setup: ----------------- \begindata INPUT_DATA_TYPE = 'ELEMENTS' OUTPUT_SPK_TYPE = 13 POLYNOM_DEGREE = 15 OBJECT_ID = 2000511 CENTER_ID = 10 REF_FRAME_NAME = 'ECLIPJ2000_DE405' PRODUCER_ID = 'NAIF/JPL' DATA_ORDER = 'EPOCH A E INC PER NOD MEAN' DATA_DELIMITER = 'TAB' LEAPSECONDS_FILE = '/kernels/gen/lsk/naif0009.tls' PCK_FILE = 'de405_sun_gm.tpc' FRAME_DEF_FILE = 'eclipj2000_de405.tf' INPUT_DATA_UNITS = ( 'ANGLES=RADIANS', 'DISTANCES=AU' ) LINES_PER_RECORD = 1 TIME_WRAPPER = '# JD TDB' SEGMENT_ID = 'Ast. 511 ephemeris by CODES (Jim Baer)' \begintext ----------------- MKSPK input (\t indicates the TAB character): ----------------- 2378495\t3.165865065169022\t0.1954365042840099\t0.2738230029326945\t5.595620791109341\t1.9622606126178066\t1.4867099008254359 2378535\t3.1659512284409934\t0.19540275430935022\t0.2738228209722\t5.595765879996406\t1.9622588214298409\t1.608773149713941 2378575\t3.1660170148375846\t0.19537290505720775\t0.2738228020501052\t5.595861239574224\t1.9622583437327963\t1.7308712260497714 2378615\t3.1660886916411073\t0.19534525541200015\t0.27382272565444016\t5.59595696159322\t1.9622556863845892\t1.852956935225319 ... 2524495\t3.1910638433062832\t0.1580169036275147\t0.27690949570456175\t6.062065288302398\t1.8155928052908263\t5.023811855731282 2524535\t3.1904006060810373\t0.15798539049688656\t0.27690432152001293\t6.063428406692523\t1.815477654071112\t5.143294384066329 2524575\t3.1898352412830384\t0.1579429380990445\t0.276903443314996\t6.064555829021579\t1.8153794513396173\t5.263039455405513 ----------------- Appendix 3: CODES Data File and ``Mu'' File =========================================================================== The following description of the CODES data files was provided by Jim Baer: ----------------- Asteroid Ephemeris BC405.2 This is a numerically-integrated ephemeris of the 300 asteroids used in the force model of the JPL DE-405 planetary ephemeris; it accounts for the mutual perturbations of all 300 asteroids upon one another, in addition to perturbations from the Sun and planets. Like DE405, this ephemeris covers the years 1800 to 2200. More specifically, entries begin at JD 2378495.0, and end at JD 2524615; there are a total of 3654 entries spaced at 40-day intervals. For each date, the ephemeris entry consists of the six classical orbital elements a in AUs e i in radians w in radians omega in radians M in radians for each of the 300 asteroids. Thus, the entry for each date consists of 1800 numbers. Each line of the text file contains a single double-precision number; there are no blank lines; as the entry for the entry for the next date begins. The elements are in the heliocentric ecliptic frame, referred to J2000. Thus, if we wish to find the classical elements for the i'th asteroid at the j'th time interval, we would seek the following lines of text: a = line 300*(j-1) + 6*(i-1) + 1 e = line 300*(j-1) + 6*(i-1) + 2 i = line 300*(j-1) + 6*(i-1) + 3 w = line 300*(j-1) + 6*(i-1) + 4 omega = line 300*(j-1) + 6*(i-1) + 5 M = line 300*(j-1) + 6*(i-1) + 6 The order in which the asteroids are presented, and the masses assumed for each asteroid, are provided in the accompanying "mu.txt" file. I sincerely hope this ephemeris will find use in high-precision applications such as collision analysis, mission design, and mass determination. Any questions should be directed to jimbaer1@earthlink.net Jim Baer July 25, 2010 ----------------- The "mu.txt" file accompanying the asteroid ephemeris data had the following contents: ----------------- 1 4.76E-10 2 1.06E-10 4 1.34E-10 29 7.80E-12 16 1.14E-11 15 1.59E-11 10 4.40E-11 7 7.30E-12 6 6.30E-12 3 1.50E-11 345 2.94E-13 12 1.02E-12 442 1.00E-13 27 1.60E-12 287 2.20E-13 43 2.03E-13 84 1.75E-13 30 9.51E-13 536 1.22E-12 163 1.35E-13 105 5.96E-13 554 3.11E-13 313 3.15E-13 115 3.62E-13 230 9.20E-13 337 2.88E-13 80 3.42E-13 9 7.40E-12 63 7.80E-13 25 3.01E-13 192 7.83E-13 304 1.10E-13 20 1.90E-12 566 1.68E-12 654 7.29E-13 135 6.94E-13 618 6.14E-13 635 3.34E-13 21 1.30E-12 42 7.15E-13 19 4.19E-12 11 2.29E-12 168 1.15E-12 17 7.00E-13 1467 4.96E-13 329 1.66E-13 46 6.74E-13 751 4.76E-13 89 2.47E-12 449 2.21E-13 334 1.33E-12 134 6.61E-13 535 1.46E-13 626 3.61E-13 5 1.26E-12 712 7.32E-13 107 5.63E-12 409 1.49E-12 362 3.32E-13 405 6.87E-13 32 3.74E-13 14 3.50E-12 91 4.67E-13 111 3.06E-12 1015 3.21E-13 404 3.29E-13 344 8.16E-13 849 3.30E-13 389 3.50E-13 347 1.88E-13 70 6.43E-13 194 1.69E-12 53 5.42E-13 78 6.19E-13 407 3.03E-13 454 1.91E-13 23 8.84E-13 124 3.16E-13 164 4.07E-13 37 9.04E-13 72 2.25E-13 224 3.30E-13 369 3.01E-13 50 3.51E-13 476 5.61E-13 713 4.14E-13 85 1.31E-12 26 6.11E-13 455 2.12E-13 144 1.00E-12 488 1.19E-12 466 5.44E-13 511 1.93E-11 240 3.96E-13 1036 2.26E-14 141 7.94E-13 97 7.93E-13 326 2.84E-13 77 4.63E-13 694 2.64E-13 145 1.22E-12 75 2.41E-13 225 6.17E-13 201 4.46E-13 324 5.10E-12 34 5.16E-13 98 4.02E-13 31 2.70E-11 175 3.63E-13 109 2.52E-13 58 2.88E-13 103 5.39E-13 59 1.58E-12 54 1.61E-12 146 8.15E-13 45 2.86E-12 209 1.44E-12 410 6.65E-13 160 1.89E-13 140 4.67E-13 156 6.25E-13 110 8.90E-13 187 7.98E-13 18 1.51E-12 387 7.22E-13 200 7.46E-13 185 1.38E-12 57 1.01E-12 247 8.57E-13 372 2.37E-12 980 4.55E-13 481 5.12E-13 521 5.46E-13 206 5.09E-13 38 5.50E-13 173 1.29E-12 36 4.15E-13 171 5.60E-13 490 1.33E-12 381 6.18E-13 128 2.35E-12 93 9.88E-13 71 4.13E-13 356 7.99E-13 127 6.62E-13 41 1.86E-12 143 2.57E-13 94 3.03E-12 39 2.80E-12 88 9.10E-12 433 3.36E-15 8 3.40E-12 532 8.68E-12 92 2.82E-12 275 5.36E-13 65 6.90E-12 444 3.60E-12 393 3.21E-13 147 8.29E-13 205 1.87E-13 28 1.26E-12 139 1.35E-12 68 1.31E-12 322 4.96E-13 416 4.44E-13 216 3.44E-12 354 2.66E-12 346 8.59E-13 236 4.55E-13 365 4.19E-13 266 4.58E-13 804 2.06E-12 385 5.45E-13 81 5.96E-13 909 5.57E-13 129 2.72E-12 508 1.02E-12 195 2.22E-13 47 1.09E-12 104 6.67E-13 426 7.24E-13 471 1.72E-12 431 3.03E-13 386 1.58E-12 238 1.15E-12 338 3.51E-13 22 4.07E-12 24 4.00E-12 674 6.56E-13 702 3.04E-12 40 8.86E-13 705 8.53E-13 776 1.22E-12 375 3.55E-12 69 3.68E-12 150 1.22E-12 117 1.16E-12 35 3.87E-13 747 1.79E-12 772 5.75E-13 360 5.47E-13 388 5.25E-13 250 7.08E-13 176 6.26E-13 162 6.92E-13 350 5.85E-13 506 4.19E-13 211 1.04E-12 514 4.22E-13 241 1.70E-12 740 2.65E-13 96 1.73E-12 663 3.62E-13 451 4.02E-12 895 1.01E-12 423 3.21E-12 95 8.88E-13 49 1.54E-12 602 6.84E-13 52 1.32E-11 159 6.88E-13 357 4.21E-13 545 4.86E-13 469 6.98E-13 373 3.10E-13 48 1.30E-11 137 1.08E-12 86 6.18E-13 121 2.71E-12 196 1.80E-12 62 3.06E-13 90 4.17E-13 791 3.91E-13 120 1.86E-12 683 1.94E-13 212 8.90E-13 283 6.94E-13 691 2.38E-13 596 5.14E-13 709 3.18E-13 191 3.64E-13 74 5.90E-13 203 5.54E-13 377 2.66E-13 112 1.33E-13 165 1.32E-12 363 1.34E-13 276 6.34E-13 739 4.37E-13 1093 5.61E-13 268 9.66E-13 1021 3.46E-13 210 2.29E-13 505 5.36E-13 99 1.31E-13 690 8.69E-13 366 2.91E-13 814 4.64E-13 788 3.93E-13 303 3.45E-13 780 2.97E-13 259 2.01E-12 489 9.56E-13 568 2.32E-13 358 2.52E-13 424 2.34E-13 412 2.65E-13 762 7.04E-13 308 9.82E-13 102 2.02E-13 56 5.12E-13 154 2.23E-12 83 7.52E-13 328 1.32E-12 769 4.25E-13 181 8.46E-13 221 7.96E-13 491 3.25E-13 349 1.94E-12 148 3.29E-13 704 1.96E-11 595 4.58E-13 213 2.02E-13 419 7.57E-13 335 2.49E-13 114 3.49E-13 233 3.83E-13 498 7.91E-13 914 1.59E-13 44 2.51E-13 790 1.74E-12 76 2.19E-12 420 9.94E-13 106 1.11E-12 130 3.32E-12 13 7.50E-12 87 7.43E-12 51 1.14E-12 773 3.11E-13 336 1.17E-13 -----------------