Goldstone Radar Observations Planning: 2007 EC and 2015 AK1
2007 EC 2007 EC was discovered by NEAT on 2007 March 2. This object will approach within 10.6 lunar distances on 2015 January 15, when it should be a moderately strong radar target at Goldstone and an imaging target at Arecibo. The absolute magnitude of 22.2 suggests a diameter of roughly 120 m, but otherwise we know nothing about its physical properties. One track is scheduled at Goldstone on January 17 and two tracks are scheduled at Arecibo on Jan. 27 and 28. 2007 EC is on NASA's NHATS list of human-accessible mission targets, so improving its orbit and estimating its physical properties are particularly important. Update: Astrometry reported on Jan. 15 from Sandlot Observatory (H36, United States) and Master II Observatory (C41, Russia) shrank the pointing uncertainties by more than three orders of magnitude to the point where additional astrometry is no longer necessary. Thank you! 2015 AK1 2015 AK1 was discovered by Pan-STARRS on January 11. This is an object roughly 40 meters in diameter and will approach within 0.014 au (5.6 lunar distances) on Jan. 18. The view period for 2015 AK1 overlaps time already scheduled on Jan. 17 for 2007 EC, so we have added this object to the existing schedule. We know very little about this object other than a rough estimate of its diameter. If previous experience is a guide, then there's a good chance that this object will be a rapid rotator. Update: Tim Lister (Las Cumbres Observatory) reports a very rapid rotation period of 3.1 minutes and a large lightcurve amplitude of 0.7 magnitudes. We expect that 2015 AK1 will not be a strong radar target, but we're hopeful that the SNRs will be sufficient for CW observations and ranging measurements.
Orbital and Physical Characteristics Provisional Designation 2007 EC 2015 AK1 Asteroid number not numbered not numbered Discoverer NEAT Pan-STARRS1 Discovery date 2007 March 02 2015 Jan 11 Orbit type Aten Apollo Close approach date 2015 Jan 15.82729 2015 Jan 18.97171 Close approach dist. 0.027 au 0.014 au Close approach dist. 10.6 lunar distances 5.6 lunar distances semimajor axis 0.927 au 1.717 au eccentricity 0.197 0.514 inclination 5.8 deg 2.8 deg perihelion distance 0.745 au 0.835 au aphelion distance 1.109 au 3.152 au MOID 0.024 au 0.014 au Tisserand parameter 6.346 absolute magnitude (H) 22.2 24.5 diameter 0.12 km 40 m +- a factor of two optical albedo unknown unknown rotation period unknown 3.1 minutes T. Lister, pers. comm. lightcurve amplitude unknown 0.7 mag T. Lister, pers. comm. pole direction unknown unknown spectral class unknown unknown Last update: 2015 January 16
2007 EC Discovery MPEC http://www.minorplanetcenter.net/mpec/K07/K07E24.html 2015 AK1 Discovery MPEC http://www.minorplanetcenter.net/mpec/K15/K15A32.html
2007 EC GOLDSTONE SNRS Assumptions: D = 0.12 km, P = 0.5 h, OC radar albedo = 0.1 w start date window RA, dec dist Runs SNR/day SNR/run 2 2015 Jan 08-09 13:47-02:33 293, +43 0.038 574 27 1 2 2015 Jan 09-10 13:41-02:56 296, +47 0.035 635 37 2 2 2015 Jan 10-11 13:35-03:28 299, +52 0.033 705 49 2 2 2015 Jan 11-12 13:30-04:14 305, +57 0.031 788 64 2 3 2015 Jan 12-13 13:27-05:22 313, +62 0.030 887 81 3 3 2015 Jan 13-14 13:29-07:08 326, +67 0.028 1007 98 3 3 2015 Jan 14-15 13:44-09:24 346, +71 0.028 1136 110 4 3 2015 Jan 15-16 14:40-10:52 12, +72 0.027 1173 120 4 3 2015 Jan 16-17 16:47-11:19 36, +69 0.028 1067 110 4 Scheduled 3 2015 Jan 17-18 18:52-11:25 51, +64 0.029 939 90 3 3 2015 Jan 18-19 20:16-11:24 61, +59 0.030 831 73 3 4 2015 Jan 19-20 21:11-11:20 68, +54 0.032 741 56 2 4 2015 Jan 20-21 21:48-11:14 72, +49 0.034 664 42 2 4 2015 Jan 21-22 22:15-11:09 76, +44 0.037 599 32 1 Goldstone SNRs assume Ptx = 450 kW and Tsys = 17 K ARECIBO SNRS start date window RA, dec dist runs SNR/day SNR/run 2015 Jan 01 15:18-17:58 284, +25 0.060 79 50 6 2015 Jan 02 15:20-17:54 284, +27 0.057 80 61 7 2015 Jan 03 15:23-17:49 285, +29 0.053 80 75 9 2015 Jan 04 15:29-17:42 286, +31 0.050 78 89 11 2015 Jan 05 15:40-17:32 287, +34 0.047 70 99 13 2015 Jan 06 16:01-17:14 289, +36 0.044 49 86 13 ...moves too far north to track from Jan. 7-23... 2015 Jan 24 01:19-01:53 80, +38 0.042 24 63 13 2015 Jan 25 00:49-02:28 82, +35 0.045 65 100 14 2015 Jan 26 00:37-02:43 83, +32 0.048 77 100 13 2015 Jan 27 00:30-02:51 84, +30 0.051 80 86 10 Scheduled 2015 Jan 28 00:25-02:56 85, +28 0.055 81 70 8 Scheduled 2015 Jan 29 00:21-02:59 86, +26 0.058 80 56 7 2015 Jan 30 00:18-03:00 87, +24 0.061 77 46 5 2015 Jan 31 00:16-03:00 88, +23 0.065 75 37 4 Arecibo SNRs assume Ptx = 900 kW and Tsys = 25 K. 2015 AK1 Goldstone SNRs New SNR estimates using the rapid rotation period = 3.2 minutes: start date window RA, dec dist runs SNR/day SNR/run 2015 Jan 14-15 23:57-15:08 107, +60 0.029 923 6 0 2015 Jan 15-16 23:16-18:01 111, +68 0.024 1335 14 0 2015 Jan 16-18 20:25-03:44 131, +81 0.018 2354 44 1 2015 Jan 18-19 09:01-01:13 269, +64 0.014 2012 100 2 2015 Jan 19-20 11:49-00:03 275, +37 0.015 1424 67 2 2015 Jan 20 13:00-23:20 278, +17 0.019 976 27 1 2015 Jan 21 13:40-22:48 279, +5 0.024 680 9 0 This object will be weaker than we expected by potentially still detectable. 2015 AK1 is circumpolar from Jan 16-19 so we set the horizons = 25 deg on those datees in order to compute rise/set times above. Arecibo SNRs start date window RA, dec dist runs SNR/day SNR/run 2015 Jan 20 13:35-16:21 277, +19 0.018 277 800 50 2015 Jan 21 13:55-16:01 279, +6 0.023 164 260 21 Arecibo SNRs assume Ptx = 600 kW and Tsys = 25 K
Track Assignments
DOY BOA BOT EOT EOA 17 0315 0445 1015 1045 DSS-14 GSSR Ast 2007 EC/2015 AK1 Goldstone track: UT UT PST Duration Round-trip DOY Date TX Window TX Window hh:mm time (sec) 17 Jan 17 0345-1015 1945-0215 Jan 16-17 6:30 28 2007 EC 17 Jan 17 0345-1015 1945-0215 Jan 16-17 6:30 18 2015 AK1. RTT changes rapidly. Note that we have transmit authorization only 30 minutes into precal. Arecibo tracks: 2007 EC UT UT PST Duration Round-trip Date TX Window TX Window hh:mm time (sec) Jan 27 0030-0251 1630-1851 Jan 26 2:21 51 Jan 28 0025-0256 1625-1856 Jan 27 2:31 55 2015 AK1 isn't scheduled at Arecibo.
Uncertainties
2007 EC JPL/Horizons solution 15, # obs: 87 (2007-2015): Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta POS_3sigma DOP_S_3sig DOP_X_3sig RT_delay_3sig 2015-Jan-15 00:00 * 346.58633 70.73326 0.02759472918207 0.814 0.38 1.39 0.001046 2015-Jan-16 00:00 * 11.12342 71.46174 0.02743112023742 0.633 0.27 1.00 0.001043 2015-Jan-17 00:00 * 33.60157 69.10835 0.02778695070413 1.098 0.46 1.69 0.001036 2015-Jan-18 00:00 * 49.47886 64.74048 0.02864653944431 1.657 0.70 2.56 0.001026 2015-Jan-19 00:00 * 59.82093 59.60320 0.02997059954917 2.116 0.89 3.25 0.001014 2015-Jan-20 00:00 *m 66.69686 54.43712 0.03170520254365 2.437 1.03 3.73 0.001006 2015-Jan-21 00:00 *m 71.48916 49.59151 0.03379141975837 2.627 1.12 4.07 0.001002 2015-Jan-22 00:00 *m 74.99016 45.20225 0.03617260142447 2.713 1.19 4.33 0.001006 2015-Jan-23 00:00 *m 77.65440 41.29742 0.03879843143421 2.723 1.25 4.55 0.001016 2015-Jan-24 00:00 *m 79.75265 37.85389 0.04162637166142 2.681 1.31 4.76 0.001035 2015-Jan-25 00:00 *m 81.45351 34.82737 0.04462152194487 2.606 1.36 4.96 0.001060 2015-Jan-26 00:00 *m 82.86632 32.16764 0.04775573640266 2.512 1.42 5.16 0.001091 2015-Jan-27 00:00 *m 84.06469 29.82599 0.05100651330360 2.409 1.47 5.36 0.001128 2015-Jan-28 00:00 *m 85.09978 27.75833 0.05435591943887 2.301 1.53 5.54 0.001170 2015-Jan-29 00:00 *m 86.00813 25.92612 0.05778965471053 2.194 1.57 5.72 0.001216 2015-Jan-30 00:00 *m 86.81653 24.29638 0.06129628252215 2.090 1.62 5.88 0.001266 2015-Jan-31 00:00 *m 87.54502 22.84109 0.06486661560052 1.990 1.66 6.03 0.001318 JPL/Horizons solution 13, #obs: 55 (51 days): Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta POS_3sigma DOP_S_3sig DOP_X_3sig RT_delay_3sig 2015-Jan-15 00:00 * 345.91675 71.16437 0.02747636691261 12029.704 1092.83 3971.86 0.806348 2015-Jan-16 00:00 * 11.11906 71.93963 0.02730705597735 11896.890 883.35 3210.50 0.845605 2015-Jan-17 00:00 * 34.15272 69.53039 0.02765860167390 11571.126 622.22 2261.43 0.875208 2015-Jan-18 00:00 * 50.19566 65.06620 0.02851545638196 11092.889 362.69 1318.18 0.894215 2015-Jan-19 00:00 * 60.51236 59.84165 0.02983818683639 10513.528 147.40 535.73 0.903609 2015-Jan-20 00:00 *m 67.31475 54.60761 0.03157254236367 9881.795 13.86 50.37 0.905584 2015-Jan-21 00:00 *m 72.03199 49.71113 0.03365922553989 9236.558 96.32 350.05 0.902662 2015-Jan-22 00:00 *m 75.46754 45.28420 0.03604126173209 8605.088 136.36 495.60 0.897066 2015-Jan-23 00:00 *m 78.07696 41.35147 0.03866809110867 8004.386 141.85 515.53 0.890462 2015-Jan-24 00:00 *m 80.12961 37.88724 0.04149701303226 7443.590 125.68 456.77 0.883965 2015-Jan-25 00:00 *m 81.79235 34.84526 0.04449302996774 6926.372 97.54 354.52 0.878240 2015-Jan-26 00:00 *m 83.17304 32.17392 0.04762794485349 6452.917 63.99 232.58 0.873639 2015-Jan-27 00:00 *m 84.34407 29.82350 0.05087923497003 6021.369 29.28 106.43 0.870306 2015-Jan-28 00:00 *m 85.35565 27.74917 0.05422896460310 5628.805 7.81 28.39 0.868258 2015-Jan-29 00:00 *m 86.24362 25.91186 0.05766284172713 5271.865 37.42 136.01 0.867442 2015-Jan-30 00:00 *m 87.03420 24.27820 0.06116944333183 4947.114 66.01 239.90 0.867765 2015-Jan-31 00:00 *m 87.74699 22.81990 0.06473959812934 4651.259 91.61 332.94 0.869119 2015 AK1 JPL/Horizons solution 4, # obs: 50 (5 days): Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta POS_3sigma DOP_S_3sig DOP_X_3sig RT_delay_3sig 2015-Jan-15 00:00 * 106.78905 58.09843 0.03138072525905 0.715 368.54 1339.44 0.066624 2015-Jan-16 00:00 * 109.56215 65.31067 0.02531394261451 1.024 340.72 1238.34 0.053702 2015-Jan-17 00:00 * 119.47488 76.45008 0.01991131831412 3.111 286.07 1039.69 0.042214 2015-Jan-18 00:00 * 240.10050 82.33805 0.01585198513211 9.148 174.77 635.18 0.033625 2015-Jan-19 00:00 * 271.38827 57.36523 0.01431812897024 18.140 17.65 64.14 0.030467 2015-Jan-20 00:00 *m 275.99449 31.55185 0.01604843684790 21.217 190.68 693.00 0.034283 2015-Jan-21 00:00 *m 277.80987 13.52842 0.02022413992839 18.424 294.29 1069.58 0.043283 2015-Jan-22 00:00 *m 278.78800 2.36029 0.02568457389413 15.077 345.18 1254.53 0.054994 2015-Jan-23 00:00 *m 279.40795 -4.73323 0.03178217391625 12.586 371.45 1350.01 0.068048 2015-Jan-24 00:00 *m 279.84445 -9.50350 0.03822256783143 10.850 386.52 1404.81 0.081828 2015-Jan-25 00:00 *m 280.17669 -12.88828 0.04486866422826 9.622 396.16 1439.84 0.096046 JPL/Horizons solution 2: Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta POS_3sigma DOP_S_3sig DOP_X_3sig RT_delay_3sig 2015-Jan-15 00:00 * 106.78806 58.09694 0.03133462085408 37.360 1789.43 6503.60 0.300019 2015-Jan-16 00:00 * 109.55868 65.30609 0.02527955845839 105.310 1644.19 5975.72 0.239678 2015-Jan-17 00:00 * 119.45198 76.43842 0.01988699312598 270.456 1342.23 4878.27 0.187261 2015-Jan-18 00:00 * 239.96467 82.36226 0.01583382167463 620.650 795.59 2891.54 0.148787 2015-Jan-19 00:00 * 271.37641 57.41644 0.01429851698716 1042.347 930.04 3380.18 0.135474 2015-Jan-20 00:00 *m 275.99019 31.60621 0.01601958294427 1088.405 1471.32 5347.46 0.161532 2015-Jan-21 00:00 *m 277.80754 13.57219 0.02018284604600 869.217 1695.65 6162.78 0.214920 2015-Jan-22 00:00 *m 278.78648 2.39398 0.02563014994129 665.652 1808.90 6574.35 0.278123 2015-Jan-23 00:00 *m 279.40684 -4.70653 0.03171444834137 525.774 1876.03 6818.34 0.345091 2015-Jan-24 00:00 *m 279.84358 -9.48151 0.03814144857889 432.154 1919.24 6975.38 0.414028 2015-Jan-25 00:00 *m 280.17596 -12.86956 0.04477407250045 367.530 1949.58 7085.65 0.484239 ********************************************************************************************** Apparent Magnitudes, Solar Elongations, Lunar Elongations, and Lunar Illumination: 2007 EC Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta APmag S-O-T /r T-O-M/Illu% 2015-Jan-09 00:00 292.68664 44.09419 0.03750459244002 19.27 66.3167 /T 117.2/ 87.1 2015-Jan-10 00:00 295.60368 48.18287 0.03504015350069 18.90 70.3364 /T 113.2/ 80.2 2015-Jan-11 00:00 299.55907 52.72974 0.03282148584060 18.52 74.8965 /T 110.0/ 72.3 2015-Jan-12 00:00 305.15702 57.67321 0.03090066507740 18.14 80.0314 /T 108.1/ 63.5 2015-Jan-13 00:00 313.47363 62.80508 0.02933618024098 17.78 85.7322 /T 107.9/ 54.1 2015-Jan-14 00:00 326.34729 67.62289 0.02818822435272 17.45 91.9216 /T 109.8/ 44.3 2015-Jan-15 00:00 345.96047 71.11364 0.02751065797080 17.17 98.4338 /T 113.5/ 34.5 2015-Jan-16 00:00 11.06649 71.88805 0.02734095284611 16.93 105.0189 /T 118.6/ 25.1 2015-Jan-17 00:00 34.03486 69.49290 0.02769161799792 16.76 111.3795 /T 124.2/ 16.4 2015-Jan-18 00:00 50.06877 65.04630 0.02854718911455 16.66 117.2325 /T 128.7/ 9.1 2015-Jan-19 00:00 60.39805 59.83592 0.02986837220133 16.61 122.3665 /T 130.6/ 3.6 2015-Jan-20 00:00 67.21586 54.61182 0.03160106650574 16.62 126.6710 /T 128.5/ 0.6 2015-Jan-21 00:00 71.94657 49.72192 0.03368609971758 16.67 130.1314 /T 122.3/ 0.5 2015-Jan-22 00:00 75.39308 45.29913 0.03606658301076 16.75 132.8033 /T 113.1/ 3.2 2015-Jan-23 00:00 78.01130 41.36885 0.03869200485404 16.85 134.7824 /T 101.9/ 8.8 2015-Jan-24 00:00 80.07109 37.90592 0.04151968472298 16.97 136.1794 /T 89.7/ 16.7 2015-Jan-25 00:00 81.73969 34.86450 0.04451462697875 17.10 137.1029 /T 77.0/ 26.3 2015-Jan-26 00:00 83.12525 32.19324 0.04764862613177 17.23 137.6501 /T 64.2/ 37.0 2015-Jan-27 00:00 84.30038 29.84259 0.05089914604027 17.37 137.9032 /T 51.4/ 47.9 2015-Jan-28 00:00 85.31546 27.76783 0.05424823581888 17.51 137.9291 /T 38.9/ 58.7 2015-Jan-29 00:00 86.20645 25.92999 0.05768158833361 17.65 137.7807 /T 26.6/ 68.8 2015-Jan-30 00:00 86.99965 24.29574 0.06118776644215 17.79 137.4994 /T 14.6/ 77.9 2015-Jan-31 00:00 87.71475 22.83683 0.06475758608900 17.92 137.1169 /T 4.588/ 85.6 2015 AK1 Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta APmag S-O-T /r T-O-M/Illu% 2015-Jan-12 00:00 104.23001 47.22600 0.05113061463057 19.30 153.4998 /T 86.1/ 63.5 2015-Jan-13 00:00 104.69334 49.80345 0.04437371327970 19.06 150.7679 /T 96.4/ 54.1 2015-Jan-14 00:00 105.41511 53.26790 0.03775619507471 18.80 147.2351 /T 106.0/ 44.3 2015-Jan-15 00:00 106.67460 58.13875 0.03134936542834 18.52 142.4085 /T 114.0/ 34.5 2015-Jan-16 00:00 109.38274 65.35536 0.02529663740714 18.24 135.3612 /T 118.5/ 25.1 2015-Jan-17 00:00 119.08150 76.50382 0.01990681894822 18.02 124.3392 /L 115.8/ 16.4 2015-Jan-18 00:00 240.79003 82.43596 0.01585590126904 18.05 106.6057 /L 101.5/ 9.1 2015-Jan-19 00:00 271.63524 57.46869 0.01431934363031 18.79 81.6040 /L 75.9/ 3.6 2015-Jan-20 00:00 276.13591 31.67655 0.01603449310025 20. 57.4236 /L 51.0/ 0.6 2015-Jan-21 00:00 277.90877 13.63807 0.02019140493333 23. 41.6258 /L 40.8/ 0.5 2015-Jan-22 00:00 278.86404 2.44860 0.02563403184092 24. 33.1240 /L 45.8/ 3.2 2015-Jan-23 00:00 279.46971 -4.66188 0.03171505294462 25. 28.9290 /L 57.9/ 8.8 2015-Jan-24 00:00 279.89643 -9.44452 0.03813966162599 26. 27.0744 /L 71.8/ 16.7 2015-Jan-25 00:00 280.22155 -12.83834 0.04477044439748 27. 26.4768 /L 86.1/ 26.3
Setups
We don't know what to expect for the bandwidth, so we're going to start with a standard CW setup: CW setup: --------------------------------------------------------------------------- TX polarization RCP RCV polarization LCP & RCP Frequency hops: no hopping Bandwidth: 4000 Hz TXoffset +500 Hz Sampling interval: 2500 x 0.1 usec FFT for PFS files: 2000 for 2.0 Hz resolution Ranging setups: --------------------------------------------------------------------------- 10-usec baud 10 usec code 127 PRP 1270 usec FFT 128 ncoh 1 bandwidth 787 Hz resolution 12.3 Hz TXOFF +100Hz (echo in bin 32 + 8 = 40) --------------------------------------------------------------------------- 11-usec baud 11 usec code 127 PRP 1397 usec FFT 64 ncoh 1 bandwidth 716 Hz resolution 11.2 Hz TXOFF +100 Hz (echo in bin 32 + 9= 41) ------------------------------------------------------------------------- 1-usec baud 1 usec code 255 FFT 512 ncoh 16 bandwidth 245 Hz resolution 0.48 Hz TXOFF +50 Hz ---------------------------------------------------------------------
Instructions
NOTE: Data should be moved to the appropriate subdirectories in aardvark:/export/data0/2007ec/raw/
POINTING:
OSOD and predicts will be on aardvark: ...not available yet... POINTING TX Offsets Date (UTC) DOY hhmmss RA Dec Macro LHA Dec RTT OSOD ... to be added ... Transmit offsets are given in millidegrees.
PRDX.OUT.14f-14-14.?? TRANSMITTER: STATION #14, RECEIVER: STATION #14 RECEIVER U.T. RANGE DOPPLER LHA DEC RA EL
2007 EC GOLDSTONE MASTERLOG
============================================================================== Receive TX Setup hops dwell code ncoh FFT runs start -stop OSOD offset Poln Notes ------------------------------------------------------------------------------
Dr. Lance A. M. Benner | PHONE: (818) 354-7412 Mail Stop 183-601 | FAX: (818) 393-4445 Jet Propulsion Laboratory | email: lance.benner@jpl.nasa.gov California Institute of Technology | Plan: To live long and prosper Pasadena, CA 91109-8099 http://echo.jpl.nasa.gov/asteroids/2007EC/2007EC_planning.html
Asteroid Radar Astronomy