Updated Ephemeris for ISEE-3

Source: JPL Horizons: NOTE: No new measurements since July 15 despite some potential unmodeled thruster pulses just prior to that. However, Arecibo signal strength on August 5th suggests s41 was within ~100 arcsec of actual. ICE may be observable visually at mag. 19-20 over the Aug 9-20 interval.

Nominal encounters for s41:

     Date (CT)      Body  CA Dist MinDist  MaxDist  Vrel  TCA3Sg  Nsigs  P_i/p
  ----------------- ----- ------- -------  ------- ------ ------ ------ -------
  2014 Aug 09.13047 Earth .001235 .001149  .001318  2.638 186.04 40.915 .000000
  2014 Aug 10.80979 Moon  .000118 .000001  .000282  2.018 243.66 2.1921 .004321

UPDATE (2014-Jul-15): Trajectory updated to JPL solution #41 (s41), based on 48 coarse Arecibo plane-of-sky angular measurements spanning May 22 - Jul 15.

Plane-of-sky uncertainties (units are arcseconds, km, km/s):

   Date__(UT)__HR:MN     RA_3sigma DEC_3sigma RNG_3sigma RNGRT_3sig
   2014-Aug-02 00:00       780.766    642.014 14031.3850  0.0570105
   2014-Aug-04 00:00      1479.369   1256.082 10321.1032  0.0552189
   2014-Aug-05 00:00      2182.470   1885.499 11009.1841  0.0543265
   2014-Aug-06 00:00      3478.347   3051.582 12681.5228  0.0538118
   2014-Aug-07 00:00      6285.085   5509.371 13931.3196  0.0551457
   2014-Aug-08 00:00     14020.531  11018.574 11569.0536  0.0645683
   2014-Aug-10 00:00      7590.364   5316.623 27551.0800  0.0865967
   2014-Aug-12 00:00     22710.084  17508.146 30241.9692  0.1064071
   2014-Aug-14 00:00     31843.193  22694.977 18375.5356  0.0156532
   2014-Aug-16 00:00     35268.764  24040.205 16171.9713  0.0269640
   2014-Aug-18 00:00     36951.706  24472.608 33196.4787  0.0499405
   2014-Aug-20 00:00     37896.044  24616.796 53638.2302  0.0630939
   2014-Aug-22 00:00     38453.318  24650.921 74030.4945  0.0704983
   2014-Aug-24 00:00     38773.710  24634.617 93572.7670  0.0742269
   2014-Aug-26 00:00     38930.728  24588.886 111937.097  0.0754814
   2014-Aug-28 00:00     38964.476  24520.542 128970.257  0.0750356
   2014-Aug-30 00:00     38899.203  24431.021 144616.210  0.0734299
   2014-Sep-01 00:00     38751.206  24319.948 158882.594  0.0710662

UPDATE (2014-Jul-10): Trajectory updated to JPL solution #36 (s36), based on 45 coarse Arecibo plane-of-sky angular measurements spanning May 22 - Jul 09.

UPDATE (2014-Jul-03): Trajectory update from ISEE-3 Reboot based on Arecibo angular data and DSN two-way Doppler.

UPDATE (2014-Jun-23): Trajectory updated to JPL solution #32 (s32), based on 42 coarse Arecibo plane-of-sky angular measurements spanning May 22 - Jun 23 ... (not delay/Doppler).

UPDATE (2014-Jun-13): Trajectory updated to JPL solution #27 (s27), based on coarse Arecibo plane-of-sky angular measurements (not delay/Doppler).

UPDATE (2014-Jun-09): Trajectory updated to JPL solution #24 (s24), based on coarse Arecibo plane-of-sky angular measurements (not delay/Doppler).

UPDATE (2014-Jun-05): Trajectory updated to JPL solution #21 (s21), based on coarse Arecibo plane-of-sky angular measurements (not delay/Doppler).

UPDATE (2014-Jun-03): Trajectory updated to JPL solution #17 (s17), based on coarse Arecibo plane-of-sky angular measurements (not delay/Doppler).

UPDATE (2014-Jun-01): The trajectory has been updated to JPL solution #6 (s6), based on coarse Arecibo plane-of-sky angular measurements (not delay/Doppler).

UPDATE (2014-May-23): While too distant/small for radar echos, Arecibo obtained one plane-of-sky measurement about 0.39 deg (RSS) from this trajectory. A full, three dimensional orbit solution update is not yet possible, but will be made available here if/when it is.

UPDATE (2014-Mar-10): Reacquired carrier signal by AMSAT-DL/Bochum: http://www.amsat-dl.org/index.php/news-mainmenu-97/199-ice-satellite-received-in-bochum

*******************************************************************************
Ephemeris / WWW_USER Sat Aug  9 12:26:38 2014 Pasadena, USA      / Horizons    
*******************************************************************************
Target body name: ICE Spacecraft (-111)           {source: Horizons_SPK:user_input_}
Center body name: Earth (399)                     {source: DE-0431LE-0431}
Center-site name: (user defined site below)
*******************************************************************************
Start time      : A.D. 2014-Aug-09 00:00:00.0000 UT      
Stop  time      : A.D. 2014-Aug-12 00:00:00.0000 UT      
Step-size       : 20 minutes
*******************************************************************************
Target pole/equ : No model available
Target radii    : (unavailable)                                                
Center geodetic : 237.920000,37.3883000,0.0000000 {E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: 237.920000,5073.94206,3851.7214 {E-lon(deg),Dxy(km),Dz(km)}
Center pole/equ : High-precision EOP model        {East-longitude +}
Center radii    : 6378.1 x 6378.1 x 6356.8 km     {Equator, meridian, pole}    
Target primary  : Earth
Vis. interferer : MOON (R_eq= 1737.400) km        {source: DE-0431LE-0431}
Rel. light bend : Sun, EARTH                      {source: DE-0431LE-0431}
Rel. lght bnd GM: 1.3271E+11, 3.9860E+05 km^3/s^2                              
Atmos refraction: NO (AIRLESS)
RA format       : DEG
Time format     : CAL 
RTS-only print  : NO       
EOP file        : eop.140808.p141030                                           
EOP coverage    : DATA-BASED 1962-JAN-20 TO 2014-AUG-08. PREDICTS-> 2014-OCT-29
Units conversion: 1 au= 149597870.700 km, c= 299792.458 km/s, 1 day= 86400.0 s 
Table cut-offs 1: Elevation (-90.0deg=NO ),Airmass (>38.000=NO), Daylight (NO )
Table cut-offs 2: Solar Elongation (  0.0,180.0=NO ),Local Hour Angle( 0.0=NO )
*****************************************************************************************
 Date__(UT)__HR:MN     R.A._(J2000.0)_DEC. Azi_(a-appr)_Elev            delta      deldot
*****************************************************************************************
$$SOE
 2014-Aug-09 00:00 *   227.93876 -43.21250 156.6710   4.0030 1.8584316492E+05  -0.3827190
 2014-Aug-09 00:20 *   229.09423 -43.41758 159.3199   4.9653 1.8540882444E+05  -0.3410627
 2014-Aug-09 00:40 *   230.25443 -43.60477 161.9996   5.8057 1.8502466348E+05  -0.2991035
 2014-Aug-09 01:00 *   231.41907 -43.77352 164.7058   6.5227 1.8469101220E+05  -0.2568964
 2014-Aug-09 01:20 *   232.58786 -43.92332 167.4344   7.1148 1.8440813676E+05  -0.2144930
 2014-Aug-09 01:40 *m  233.76050 -44.05374 170.1803   7.5810 1.8417624307E+05  -0.1719422
 2014-Aug-09 02:00 *m  234.93668 -44.16439 172.9386   7.9206 1.8399548024E+05  -0.1292899
 2014-Aug-09 02:20 *m  236.11607 -44.25498 175.7040   8.1334 1.8386594375E+05  -0.0865795
 2014-Aug-09 02:40 *m  237.29833 -44.32526 178.4710   8.2193 1.8378767822E+05  -0.0438525
 2014-Aug-09 03:00 *t  238.48312 -44.37507 181.2343   8.1787 1.8376067962E+05  -0.0011485
 2014-Aug-09 03:20 Cm  239.67006 -44.40432 183.9884   8.0125 1.8378489701E+05   0.0414940
 2014-Aug-09 03:40 Nm  240.85879 -44.41299 186.7282   7.7216 1.8386023375E+05   0.0840370
 2014-Aug-09 04:00 Nm  242.04891 -44.40114 189.4488   7.3074 1.8398654801E+05   0.1264432
 2014-Aug-09 04:20 Am  243.24003 -44.36889 192.1455   6.7716 1.8416365283E+05   0.1686747
 2014-Aug-09 04:40 Am  244.43173 -44.31643 194.8140   6.1159 1.8439131550E+05   0.2106929
 2014-Aug-09 05:00  m  245.62360 -44.24405 197.4505   5.3426 1.8466925644E+05   0.2524583
 2014-Aug-09 05:20  m  246.81521 -44.15208 200.0514   4.4539 1.8499714756E+05   0.2939297
 2014-Aug-09 05:40  m  248.00611 -44.04091 202.6140   3.4522 1.8537461020E+05   0.3350638
 2014-Aug-09 06:00  m  249.19586 -43.91102 205.1358   2.3401 1.8580121264E+05   0.3758153
 2014-Aug-09 06:20  m  250.38402 -43.76293 207.6147   1.1204 1.8627646738E+05   0.4161367
 2014-Aug-09 06:40  m  251.57013 -43.59721 210.0494  -0.2043 1.8679982811E+05   0.4559775
 2014-Aug-09 07:00  s  252.75372 -43.41449 212.4388  -1.6311 1.8737068670E+05   0.4952850
 2014-Aug-09 07:20  m  253.93434 -43.21545 214.7823  -3.1572 1.8798837005E+05   0.5340038
 2014-Aug-09 07:40  m  255.11151 -43.00080 217.0798  -4.7797 1.8865213711E+05   0.5720761
 2014-Aug-09 08:00  m  256.28479 -42.77129 219.3316  -6.4956 1.8936117608E+05   0.6094417
 2014-Aug-09 08:20  m  257.45370 -42.52771 221.5383  -8.3022 1.9011460185E+05   0.6460388
 2014-Aug-09 08:40  m  258.61777 -42.27086 223.7009 -10.1965 1.9091145396E+05   0.6818036
 2014-Aug-09 09:00  m  259.77656 -42.00158 225.8207 -12.1757 1.9175069487E+05   0.7166716
 2014-Aug-09 09:20  m  260.92959 -41.72070 227.8995 -14.2370 1.9263120900E+05   0.7505773
 2014-Aug-09 09:40  m  262.07642 -41.42908 229.9392 -16.3775 1.9355180220E+05   0.7834554
 2014-Aug-09 10:00  m  263.21658 -41.12759 231.9421 -18.5946 1.9451120216E+05   0.8152410
 2014-Aug-09 10:20  m  264.34964 -40.81708 233.9109 -20.8855 1.9550805936E+05   0.8458705
 2014-Aug-09 10:40  m  265.47514 -40.49840 235.8483 -23.2476 1.9654094898E+05   0.8752821
 2014-Aug-09 11:00  m  266.59265 -40.17241 237.7579 -25.6783 1.9760837360E+05   0.9034167
 2014-Aug-09 11:20  m  267.70172 -39.83993 239.6432 -28.1749 1.9870876668E+05   0.9302183
 2014-Aug-09 11:40  m  268.80193 -39.50178 241.5085 -30.7349 1.9984049700E+05   0.9556352
 2014-Aug-09 12:00 Am  269.89285 -39.15875 243.3587 -33.3559 2.0100187383E+05   0.9796201
 2014-Aug-09 12:20 N   270.97405 -38.81161 245.1993 -36.0353 2.0219115301E+05   1.0021313
 2014-Aug-09 12:40 N   272.04511 -38.46111 247.0366 -38.7708 2.0340654374E+05   1.0231330
 2014-Aug-09 13:00 C   273.10563 -38.10795 248.8785 -41.5598 2.0464621617E+05   1.0425959
 2014-Aug-09 13:20 *   274.15519 -37.75282 250.7342 -44.4000 2.0590830963E+05   1.0604980
 2014-Aug-09 13:40 *   275.19338 -37.39635 252.6152 -47.2889 2.0719094150E+05   1.0768248
 2014-Aug-09 14:00 *   276.21980 -37.03916 254.5363 -50.2239 2.0849221668E+05   1.0915701
 2014-Aug-09 14:20 *   277.23407 -36.68182 256.5164 -53.2024 2.0981023751E+05   1.1047359
 2014-Aug-09 14:40 *   278.23577 -36.32486 258.5811 -56.2215 2.1114311410E+05   1.1163330
 2014-Aug-09 15:00 *   279.22454 -35.96877 260.7660 -59.2779 2.1248897499E+05   1.1263815
 2014-Aug-09 15:20 *   280.19999 -35.61402 263.1222 -62.3680 2.1384597810E+05   1.1349103
 2014-Aug-09 15:40 *   281.16174 -35.26101 265.7269 -65.4867 2.1521232173E+05   1.1419578
 2014-Aug-09 16:00 *   282.10942 -34.91012 268.7023 -68.6273 2.1658625577E+05   1.1475715
 2014-Aug-09 16:20 *   283.04268 -34.56169 272.2548 -71.7797 2.1796609276E+05   1.1518082
 2014-Aug-09 16:40 *   283.96116 -34.21602 276.7605 -74.9260 2.1935021894E+05   1.1547340
 2014-Aug-09 17:00 *   284.86451 -33.87335 282.9754 -78.0318 2.2073710503E+05   1.1564236
 2014-Aug-09 17:20 *   285.75240 -33.53393 292.6074 -81.0164 2.2212531677E+05   1.1569604
 2014-Aug-09 17:40 *   286.62450 -33.19794 309.9086 -83.6545 2.2351352509E+05   1.1564364
 2014-Aug-09 18:00 *   287.48049 -32.86552 342.9518 -85.2532 2.2490051581E+05   1.1549510
 2014-Aug-09 18:20 *   288.32008 -32.53679  23.6769 -84.7015 2.2628519882E+05   1.1526113
 2014-Aug-09 18:40 *   289.14297 -32.21185  48.5989 -82.4219 2.2766661663E+05   1.1495312
 2014-Aug-09 19:00 *   289.94888 -31.89074  61.6015 -79.4602 2.2904395225E+05   1.1458309
 2014-Aug-09 19:20 *   290.73757 -31.57350  69.3582 -76.2338 2.3041653625E+05   1.1416361
 2014-Aug-09 19:40 *   291.50880 -31.26012  74.6608 -72.8797 2.3178385309E+05   1.1370772
 2014-Aug-09 20:00 *   292.26233 -30.95057  78.6702 -69.4515 2.3314554640E+05   1.1322890
 2014-Aug-09 20:20 *   292.99798 -30.64480  81.9297 -65.9741 2.3450142339E+05   1.1274093
 2014-Aug-09 20:40 *   293.71558 -30.34273  84.7232 -62.4614 2.3585145817E+05   1.1225782
 2014-Aug-09 21:00 *   294.41496 -30.04427  87.2128 -58.9219 2.3719579401E+05   1.1179373
 2014-Aug-09 21:20 *   295.09602 -29.74930  89.4984 -55.3616 2.3853474436E+05   1.1136286
 2014-Aug-09 21:40 *   295.75866 -29.45768  91.6448 -51.7852 2.3986879282E+05   1.1097934
 2014-Aug-09 22:00 *   296.40282 -29.16927  93.6969 -48.1968 2.4119859171E+05   1.1065715
 2014-Aug-09 22:20 *   297.02847 -28.88389  95.6872 -44.6001 2.4252495947E+05   1.1040997
 2014-Aug-09 22:40 *   297.63562 -28.60139  97.6403 -40.9985 2.4384887670E+05   1.1025112
 2014-Aug-09 23:00 *   298.22431 -28.32156  99.5757 -37.3958 2.4517148088E+05   1.1019342
 2014-Aug-09 23:20 *   298.79462 -28.04423 101.5094 -33.7956 2.4649405979E+05   1.1024908
 2014-Aug-09 23:40 *   299.34667 -27.76917 103.4554 -30.2018 2.4781804349E+05   1.1042959
 2014-Aug-10 00:00 *   299.88063 -27.49620 105.4263 -26.6188 2.4914499513E+05   1.1074561
 2014-Aug-10 00:20 *   300.39671 -27.22511 107.4337 -23.0511 2.5047660029E+05   1.1120687
 2014-Aug-10 00:40 *   300.89514 -26.95569 109.4888 -19.5040 2.5181465519E+05   1.1182207
 2014-Aug-10 01:00 *   301.37622 -26.68774 111.6026 -15.9829 2.5316105361E+05   1.1259875
 2014-Aug-10 01:20 *   301.84029 -26.42106 113.7865 -12.4943 2.5451777266E+05   1.1354324
 2014-Aug-10 01:40 *   302.28773 -26.15545 116.0518  -9.0451 2.5588685756E+05   1.1466056
 2014-Aug-10 02:00 *   302.71895 -25.89073 118.4106  -5.6433 2.5727040535E+05   1.1595431
 2014-Aug-10 02:20 *m  303.13444 -25.62673 120.8752  -2.2977 2.5867054785E+05   1.1742667
 2014-Aug-10 02:40 *r  303.53469 -25.36327 123.4587   0.9817 2.6008943383E+05   1.1907828
 2014-Aug-10 03:00 *m  303.92026 -25.10021 126.1747   4.1837 2.6152921062E+05   1.2090826
 2014-Aug-10 03:20 Cm  304.29173 -24.83742 129.0374   7.2957 2.6299200529E+05   1.2291411
 2014-Aug-10 03:40 Nm  304.64973 -24.57476 132.0612  10.3036 2.6447990567E+05   1.2509178
 2014-Aug-10 04:00 Nm  304.99492 -24.31214 135.2604  13.1917 2.6599494112E+05   1.2743560
 2014-Aug-10 04:20 Am  305.32797 -24.04947 138.6487  15.9423 2.6753906366E+05   1.2993833
 2014-Aug-10 04:40 Am  305.64962 -23.78669 142.2388  18.5363 2.6911412921E+05   1.3259122
 2014-Aug-10 05:00  m  305.96059 -23.52374 146.0408  20.9526 2.7072187947E+05   1.3538399
 2014-Aug-10 05:20  m  306.26163 -23.26061 150.0615  23.1690 2.7236392453E+05   1.3830499
 2014-Aug-10 05:40  m  306.55353 -22.99727 154.3028  25.1618 2.7404172631E+05   1.4134120
 2014-Aug-10 06:00  m  306.83705 -22.73376 158.7601  26.9070 2.7575658321E+05   1.4447840
 2014-Aug-10 06:20  m  307.11298 -22.47009 163.4211  28.3812 2.7750961598E+05   1.4770123
 2014-Aug-10 06:40  m  307.38210 -22.20632 168.2645  29.5620 2.7930175508E+05   1.5099335
 2014-Aug-10 07:00  m  307.64519 -21.94252 173.2600  30.4300 2.8113372969E+05   1.5433758
 2014-Aug-10 07:20  m  307.90303 -21.67877 178.3685  30.9697 2.8300605836E+05   1.5771603
 2014-Aug-10 07:40  m  308.15635 -21.41518 183.5443  31.1706 2.8491904167E+05   1.6111029
 2014-Aug-10 08:00  t  308.40590 -21.15186 188.7377  31.0281 2.8687275673E+05   1.6450155
 2014-Aug-10 08:20  m  308.65239 -20.88894 193.8986  30.5440 2.8886705374E+05   1.6787082
 2014-Aug-10 08:40  m  308.89649 -20.62657 198.9799  29.7262 2.9090155464E+05   1.7119909
 2014-Aug-10 09:00  m  309.13885 -20.36488 203.9407  28.5878 2.9297565380E+05   1.7446747
 2014-Aug-10 09:20  m  309.38009 -20.10404 208.7483  27.1465 2.9508852084E+05   1.7765741
 2014-Aug-10 09:40  m  309.62078 -19.84421 213.3794  25.4232 2.9723910546E+05   1.8075085
 2014-Aug-10 10:00  m  309.86146 -19.58556 217.8200  23.4406 2.9942614431E+05   1.8373036
 2014-Aug-10 10:20  m  310.10261 -19.32825 222.0645  21.2222 3.0164816972E+05   1.8657935
 2014-Aug-10 10:40  m  310.34468 -19.07245 226.1146  18.7915 3.0390352040E+05   1.8928216
 2014-Aug-10 11:00  m  310.58805 -18.81833 229.9774  16.1711 3.0619035370E+05   1.9182425
 2014-Aug-10 11:20  m  310.83309 -18.56604 233.6644  13.3824 3.0850665969E+05   1.9419229
 2014-Aug-10 11:40  m  311.08008 -18.31574 237.1903  10.4451 3.1085027657E+05   1.9637432
 2014-Aug-10 12:00 Am  311.32928 -18.06758 240.5716   7.3776 3.1321890750E+05   1.9835982
 2014-Aug-10 12:20 Nm  311.58089 -17.82170 243.8261   4.1966 3.1561013867E+05   2.0013983
 2014-Aug-10 12:40 Nm  311.83507 -17.57823 246.9728   0.9171 3.1802145838E+05   2.0170700
 2014-Aug-10 13:00 Cs  312.09191 -17.33728 250.0309  -2.4469 3.2045027706E+05   2.0305570
 2014-Aug-10 13:20 C   312.35149 -17.09896 253.0205  -5.8828 3.2289394800E+05   2.0418206
 2014-Aug-10 13:40 *   312.61382 -16.86336 255.9620  -9.3790 3.2534978859E+05   2.0508398
 2014-Aug-10 14:00 *   312.87889 -16.63055 258.8771 -12.9244 3.2781510202E+05   2.0576117
 2014-Aug-10 14:20 *   313.14662 -16.40059 261.7882 -16.5087 3.3028719885E+05   2.0621515
 2014-Aug-10 14:40 *   313.41694 -16.17352 264.7200 -20.1216 3.3276341839E+05   2.0644919
 2014-Aug-10 15:00 *   313.68971 -15.94935 267.6992 -23.7531 3.3524114927E+05   2.0646821
 2014-Aug-10 15:20 *   313.96478 -15.72808 270.7563 -27.3925 3.3771784837E+05   2.0627863
 2014-Aug-10 15:40 *   314.24198 -15.50970 273.9261 -31.0286 3.4019105715E+05   2.0588807
 2014-Aug-10 16:00 *   314.52112 -15.29413 277.2494 -34.6488 3.4265841360E+05   2.0530490
 2014-Aug-10 16:20 *   314.80200 -15.08130 280.7749 -38.2385 3.4511765733E+05   2.0453754
 2014-Aug-10 16:40 *   315.08440 -14.87110 284.5618 -41.7804 3.4756662415E+05   2.0359339
 2014-Aug-10 17:00 *   315.36813 -14.66338 288.6820 -45.2532 3.5000322521E+05   2.0247730
 2014-Aug-10 17:20 *   315.65299 -14.45796 293.2239 -48.6301 3.5242540447E+05   2.0118952
 2014-Aug-10 17:40 *   315.93881 -14.25463 298.2949 -51.8766 3.5483106901E+05   1.9972322
 2014-Aug-10 18:00 *   316.22542 -14.05316 304.0227 -54.9477 3.5721799040E+05   1.9806237
 2014-Aug-10 18:20 *   316.51267 -13.85331 310.5505 -57.7852 3.5958368820E+05   1.9618117
 2014-Aug-10 18:40 *   316.80042 -13.65485 318.0222 -60.3143 3.6192532831E+05   1.9404749
 2014-Aug-10 19:00 *   317.08847 -13.45762 326.5457 -62.4431 3.6423969679E+05   1.9163222
 2014-Aug-10 19:20 *   317.37658 -13.26153 336.1306 -64.0663 3.6652331870E+05   1.8892353
 2014-Aug-10 19:40 *   317.66437 -13.06661 346.6122 -65.0798 3.6877275096E+05   1.8594022
 2014-Aug-10 20:00 *   317.95137 -12.87300 357.6107 -65.4034 3.7098498496E+05   1.8273539
 2014-Aug-10 20:20 *   318.23699 -12.68091   8.5921 -65.0068 3.7315781287E+05   1.7938685
 2014-Aug-10 20:40 *   318.52059 -12.49057  19.0265 -63.9201 3.7529002233E+05   1.7597967
 2014-Aug-10 21:00 *   318.80149 -12.30219  28.5448 -62.2219 3.7738138392E+05   1.7259057
 2014-Aug-10 21:20 *   319.07905 -12.11594  36.9923 -60.0145 3.7943249510E+05   1.6928001
 2014-Aug-10 21:40 *   319.35268 -11.93195  44.3848 -57.4004 3.8144457528E+05   1.6609154
 2014-Aug-10 22:00 *   319.62182 -11.75027  50.8327 -54.4688 3.8341928057E+05   1.6305508
 2014-Aug-10 22:20 *   319.88600 -11.57092  56.4796 -51.2920 3.8535856595E+05   1.6019119
 2014-Aug-10 22:40 *   320.14478 -11.39388  61.4676 -47.9262 3.8726459521E+05   1.5751464
 2014-Aug-10 23:00 *   320.39779 -11.21910  65.9228 -44.4146 3.8913968741E+05   1.5503686
 2014-Aug-10 23:20 *   320.64470 -11.04652  69.9510 -40.7901 3.9098628714E+05   1.5276752
 2014-Aug-10 23:40 *   320.88523 -10.87606  73.6393 -37.0782 3.9280694876E+05   1.5071534
 2014-Aug-11 00:00 *   321.11913 -10.70762  77.0589 -33.2990 3.9460432737E+05   1.4888843
 2014-Aug-11 00:20 *   321.34622 -10.54111  80.2680 -29.4685 3.9638117263E+05   1.4729444
 2014-Aug-11 00:40 *   321.56633 -10.37643  83.3148 -25.5999 3.9814032256E+05   1.4594044
 2014-Aug-11 01:00 *   321.77933 -10.21348  86.2399 -21.7046 3.9988469638E+05   1.4483286
 2014-Aug-11 01:20 *   321.98516 -10.05217  89.0782 -17.7925 4.0161728548E+05   1.4397727
 2014-Aug-11 01:40 *   322.18376  -9.89240  91.8601 -13.8725 4.0334114249E+05   1.4337828
 2014-Aug-11 02:00 *   322.37514  -9.73408  94.6134  -9.9533 4.0505936837E+05   1.4303932
 2014-Aug-11 02:20 *   322.55931  -9.57710  97.3637  -6.0432 4.0677509775E+05   1.4296254
 2014-Aug-11 02:40 *   322.73636  -9.42140 100.1355  -2.1509 4.0849148262E+05   1.4314867
 2014-Aug-11 03:00 *r  322.90638  -9.26689 102.9529   1.7146 4.1021167460E+05   1.4359690
 2014-Aug-11 03:20 Cm  323.06953  -9.11349 105.8402   5.5436 4.1193880624E+05   1.4430484
 2014-Aug-11 03:40 Nm  323.22597  -8.96113 108.8228   9.3252 4.1367597128E+05   1.4526843
 2014-Aug-11 04:00 Nm  323.37591  -8.80976 111.9271  13.0473 4.1542620445E+05   1.4648188
 2014-Aug-11 04:20 Am  323.51960  -8.65931 115.1813  16.6961 4.1719246081E+05   1.4793769
 2014-Aug-11 04:40 Am  323.65731  -8.50973 118.6160  20.2556 4.1897759507E+05   1.4962664
 2014-Aug-11 05:00  m  323.78934  -8.36100 122.2637  23.7072 4.2078434105E+05   1.5153781
 2014-Aug-11 05:20  m  323.91602  -8.21305 126.1591  27.0293 4.2261529150E+05   1.5365862
 2014-Aug-11 05:40  m  324.03771  -8.06588 130.3381  30.1965 4.2447287862E+05   1.5597491
 2014-Aug-11 06:00  m  324.15478  -7.91945 134.8368  33.1798 4.2635935539E+05   1.5847098
 2014-Aug-11 06:20  m  324.26762  -7.77375 139.6884  35.9454 4.2827677805E+05   1.6112975
 2014-Aug-11 06:40  m  324.37665  -7.62878 144.9199  38.4556 4.3022698985E+05   1.6393282
 2014-Aug-11 07:00  m  324.48229  -7.48451 150.5465  40.6690 4.3221160624E+05   1.6686066
 2014-Aug-11 07:20  m  324.58496  -7.34097 156.5650  42.5420 4.3423200186E+05   1.6989269
 2014-Aug-11 07:40  m  324.68513  -7.19816 162.9470  44.0312 4.3628929920E+05   1.7300748
 2014-Aug-11 08:00  m  324.78322  -7.05609 169.6341  45.0973 4.3838435932E+05   1.7618292
 2014-Aug-11 08:20  m  324.87968  -6.91477 176.5371  45.7089 4.4051777459E+05   1.7939638
 2014-Aug-11 08:40  t  324.97495  -6.77424 183.5425  45.8470 4.4268986360E+05   1.8262488
 2014-Aug-11 09:00  m  325.06946  -6.63451 190.5242  45.5073 4.4490066829E+05   1.8584531
 2014-Aug-11 09:20  m  325.16364  -6.49562 197.3598  44.7012 4.4714995330E+05   1.8903462
 2014-Aug-11 09:40  m  325.25790  -6.35759 203.9456  43.4542 4.4943720765E+05   1.9216994
 2014-Aug-11 10:00  m  325.35263  -6.22046 210.2061  41.8021 4.5176164858E+05   1.9522887
 2014-Aug-11 10:20  m  325.44820  -6.08426 216.0969  39.7868 4.5412222762E+05   1.9818957
 2014-Aug-11 10:40  m  325.54498  -5.94903 221.6020  37.4524 4.5651763883E+05   2.0103098
 2014-Aug-11 11:00  m  325.64328  -5.81480 226.7277  34.8423 4.5894632906E+05   2.0373298
 2014-Aug-11 11:20  m  325.74341  -5.68162 231.4957  31.9967 4.6140651011E+05   2.0627656
 2014-Aug-11 11:40  m  325.84565  -5.54950 235.9373  28.9518 4.6389617279E+05   2.0864391
 2014-Aug-11 12:00 Am  325.95025  -5.41849 240.0882  25.7399 4.6641310255E+05   2.1081863
 2014-Aug-11 12:20 Nm  326.05742  -5.28862 243.9856  22.3888 4.6895489671E+05   2.1278579
 2014-Aug-11 12:40 Nm  326.16734  -5.15992 247.6663  18.9226 4.7151898298E+05   2.1453206
 2014-Aug-11 13:00 Cm  326.28017  -5.03241 251.1655  15.3623 4.7410263918E+05   2.1604581
 2014-Aug-11 13:20 Cm  326.39602  -4.90613 254.5165  11.7261 4.7670301399E+05   2.1731715
 2014-Aug-11 13:40 *m  326.51499  -4.78109 257.7505   8.0299 4.7931714843E+05   2.1833804
 2014-Aug-11 14:00 *m  326.63712  -4.65732 260.8973   4.2879 4.8194199804E+05   2.1910228
 2014-Aug-11 14:20 *m  326.76244  -4.53482 263.9852   0.5132 4.8457445549E+05   2.1960559
 2014-Aug-11 14:40 *s  326.89093  -4.41362 267.0418  -3.2824 4.8721137347E+05   2.1984559
 2014-Aug-11 15:00 *   327.02255  -4.29372 270.0947  -7.0872 4.8984958767E+05   2.1982182
 2014-Aug-11 15:20 *   327.15724  -4.17513 273.1717 -10.8900 4.9248593968E+05   2.1953573
 2014-Aug-11 15:40 *   327.29488  -4.05785 276.3018 -14.6792 4.9511729964E+05   2.1899062
 2014-Aug-11 16:00 *   327.43535  -3.94188 279.5161 -18.4426 4.9774058861E+05   2.1819166
 2014-Aug-11 16:20 *   327.57849  -3.82722 282.8482 -22.1671 5.0035280025E+05   2.1714578
 2014-Aug-11 16:40 *   327.72413  -3.71386 286.3350 -25.8376 5.0295102195E+05   2.1586166
 2014-Aug-11 17:00 *   327.87205  -3.60178 290.0182 -29.4371 5.0553245514E+05   2.1434961
 2014-Aug-11 17:20 *   328.02205  -3.49099 293.9444 -32.9457 5.0809443467E+05   2.1262154
 2014-Aug-11 17:40 *   328.17386  -3.38145 298.1658 -36.3396 5.1063444717E+05   2.1069083
 2014-Aug-11 18:00 *   328.32723  -3.27316 302.7403 -39.5899 5.1315014830E+05   2.0857225
 2014-Aug-11 18:20 *   328.48189  -3.16609 307.7299 -42.6624 5.1563937877E+05   2.0628185
 2014-Aug-11 18:40 *   328.63755  -3.06021 313.1977 -45.5156 5.1810017910E+05   2.0383686
 2014-Aug-11 19:00 *   328.79391  -2.95551 319.2009 -48.1005 5.2053080292E+05   2.0125556
 2014-Aug-11 19:20 *   328.95066  -2.85196 325.7800 -50.3609 5.2292972894E+05   1.9855715
 2014-Aug-11 19:40 *   329.10748  -2.74952 332.9430 -52.2354 5.2529567129E+05   1.9576166
 2014-Aug-11 20:00 *   329.26406  -2.64818 340.6471 -53.6611 5.2762758841E+05   1.9288975
 2014-Aug-11 20:20 *   329.42008  -2.54789 348.7843 -54.5815 5.2992469027E+05   1.8996265
 2014-Aug-11 20:40 *   329.57521  -2.44863 357.1809 -54.9548 5.3218644394E+05   1.8700198
 2014-Aug-11 21:00 *   329.72913  -2.35036   5.6172 -54.7618 5.3441257751E+05   1.8402958
 2014-Aug-11 21:20 *   329.88154  -2.25306  13.8657 -54.0107 5.3660308227E+05   1.8106746
 2014-Aug-11 21:40 *   330.03211  -2.15669  21.7323 -52.7345 5.3875821319E+05   1.7813754
 2014-Aug-11 22:00 *   330.18056  -2.06121  29.0839 -50.9844 5.4087848762E+05   1.7526159
 2014-Aug-11 22:20 *   330.32659  -1.96661  35.8551 -48.8208 5.4296468225E+05   1.7246105
 2014-Aug-11 22:40 *   330.46991  -1.87284  42.0372 -46.3057 5.4501782836E+05   1.6975690
 2014-Aug-11 23:00 *   330.61028  -1.77987  47.6606 -43.4969 5.4703920531E+05   1.6716947
 2014-Aug-11 23:20 *   330.74743  -1.68768  52.7778 -40.4454 5.4903033225E+05   1.6471837
 2014-Aug-11 23:40 *   330.88115  -1.59624  57.4504 -37.1950 5.5099295828E+05   1.6242230
 2014-Aug-12 00:00 *   331.01120  -1.50551  61.7411 -33.7820 5.5292905080E+05   1.6029893
$$EOE
*****************************************************************************************
Column meaning: TIME

Prior to 1962, times are UT1. Dates thereafter are UTC. Any 'b' symbol in the 1st-column denotes a B.C. date. First-column blank (" ") denotes an A.D. date. Calendar dates prior to 1582-Oct-15 are in the Julian calendar system. Later calendar dates are in the Gregorian system.

Time tags refer to the same instant throughout the universe, regardless of where the observer is located.

The dynamical Coordinate Time scale is used internally. It is equivalent to the current IAU definition of "TDB". Conversion between CT and the selected non-uniform UT output scale has not been determined for UTC times after the next July or January 1st. The last known leap-second is used over any future interval.

NOTE: "n.a." in output means quantity "not available" at the print-time.

SOLAR PRESENCE (OBSERVING SITE)
Time tag is followed by a blank, then a solar-presence symbol:

'*' Daylight (refracted solar upper-limb on or above apparent horizon)
'C' Civil twilight/dawn
'N' Nautical twilight/dawn
'A' Astronomical twilight/dawn
' ' Night OR geocentric ephemeris

LUNAR PRESENCE WITH TARGET RISE/TRANSIT/SET MARKER (OBSERVING SITE)
The solar-presence symbol is immediately followed by another marker symbol:

'm' Refracted upper-limb of Moon on or above apparent horizon
' ' Refracted upper-limb of Moon below apparent horizon OR geocentric
'r' Rise (target body on or above cut-off RTS elevation)
't' Transit (target body at or past local maximum RTS elevation)
's' Set (target body on or below cut-off RTS elevation)

RTS MARKERS (TVH) Rise and set are with respect to the reference ellipsoid true visual horizon defined by the elevation cut-off angle. Horizon dip and yellow-light refraction (Earth only) are considered. Accuracy is < or = to twice the requested search step-size.

R.A._(J2000.0)_DEC. = J2000.0 astrometric right ascension and declination of target center. Adjusted for light-time. Units: DEGREES

Azi_(a-appr)_Elev = Airless apparent azimuth and elevation of target center. Adjusted for light-time, the gravitational deflection of light, stellar aberration, precession and nutation. Azimuth measured North(0) -> East(90) -> South(180) -> West(270) -> North (360). Elevation is with respect to plane perpendicular to local zenith direction. TOPOCENTRIC ONLY. Units: DEGREES

delta deldot = Range ("delta") and range-rate ("delta-dot") of the target center relative to the observer at the instant light seen by the observer at print-time would have left the target center (print-time minus down-leg light-time); the distance traveled by a light ray emanating from the center of the target and recorded by the observer at print-time. "deldot" is a projection of the velocity vector along this ray, the light-time-corrected line-of-sight from the coordinate center, and indicates relative motion. A positive "deldot" means the target center is moving away from the observer (coordinate center). A negative "deldot" means the target center is moving toward the observer. Units: KM and KM/S

SPACECRAFT TRAJECTORY
Trajectory name Start Stop
-------------------------------------------------- ----------- -----------
ice_s41 2014-Jan-01 2014-Dec-31

BACKGROUND: Launched 1978-Aug-12 15:12 UTC on a Delta 2914, the International Sun-Earth Explorer 3 was the third of a trio of spacecraft launched to study interplanetary space; Earth's magnetosphere and its interaction with the solar wind. ISEE-1 and 2 were Earth-orbiters. ISEE-3 was the first spacecraft to orbit a libration point (Earth-Sun L1, about 1.5 million km from Earth) beginning 1978-Nov-20. The mission was managed by NASA/GSFC.

After completion of its primary mission, it was renamed International Cometary Explorer (ICE) and sent to study comet Giacobini-Zinner and comet Halley. Fifteen maneuvers and five lunar passes (the last on 1983-Dec-22, at an altitude of 119.4 km, not far from the Apollo 11 landing site on the surface) were used to maneuver it to the heliocentric escape orbit achieved 1983-Dec-22.

It was the first spacecraft to fly past a comet, being initially maneuvered to a point 26550 km behind comet Giacobini-Zinner on 1985-Jun-05 so as to sample the tail, then approached the nucleus to within 7862 km on 1985-Sep-11 with a relative velocity of 20.7 km/s, confirming for the first time theories that comets are 'dirty snowballs' of ice and rock. The spacecraft later flew between the Sun and comet Halley on 1986-Mar-28, 31 million km from the comet.

NASA headquarters approved an update to the ICE mission in 1991: a heliospheric mission consisting of investigations of coronal mass ejections in coordination with ground-based observations, continued cosmic ray studies, and special-period observations such as when ICE and Ulysses were on the same solar radial line. By May 1995, ICE was being operated with only a low duty cycle, with some support being provided by the Ulysses project for data analysis. Two years later, on May 5, 1997, NASA authorized termination of operations.

Twelve of its thirteen instruments were working and the spacecraft retained a 150 m/s delta-V fuel capacity.

At 20:49 UTC on September 18, 2008, the 70-meter Goldstone antenna DSS-14 locked onto the carrier signal of the ISEE-3/ICE spacecraft, still transmitting and relatively close to the position based on predictions from several years earlier. The remainder of the 3-hour track was then used to gather Doppler tracking data for future use.

When last contacted, the spacecraft was on a trajectory that will bring it close to Earth in August 2014.

Current transmitter hardware of the Deep Space Network no longer includes the equipment needed to transmit commands to ISEE-3 without some modification, but the spacecraft's transmitter signal could still be detected and down-linked data understood.

PHYSICAL DATA:
Cylindrical: 1.7-m diameter x 1.6-m height
Mass : 390 kg (478 kg at launch)
Spin rate : 20 rpm
Solar power: 160 watts (cells cover body surface)
Two 3-meter booms carrier magnetometer and plasma wave sensors.
Four antennas span 91-meters for radio and plasma wave studies.

Computations by ...
Solar System Dynamics Group, Horizons On-Line Ephemeris System
4800 Oak Grove Drive, Jet Propulsion Laboratory
Pasadena, CA 91109 USA
Information: http://ssd.jpl.nasa.gov/
Connect : telnet://ssd.jpl.nasa.gov:6775 (via browser)
telnet ssd.jpl.nasa.gov 6775 (via command-line)
Author : Jon.Giorgini@jpl.nasa.gov

*****************************************************************************************

About Space College

  Space News and Other Sites