Goldstone Radar Observations Planning: (5645) 1990 SP


Background


1990 SP was discovered on September 20, 1990 by Rob McNaught at Siding
Spring, Australia, as part of the Anglo-Australian Near-Earth Asteroid Survey (AANEAS).

This asteroid has been studied extensively and a number of its physical properties are 
reasonably well known.  Photometry reported by Pravec et al. (2005) indicates slow, 
probably non-principal rotation with a fundamental period of about 30.4 hours. 
The lightcurve amplitude of 0.7 magnitudes suggests an elongated shape. 

Visible-NIR spectroscopy reported by Lazzarin et al. (2004) places 1990 SP into the Xe
spectral class that is consistent with a wide range of compositions and optical
albedos.  Thermal infrared observations by the Spitzer Space Telescope (Mueller et al. 2011)
give a diameter of 2.2 km and an optical albedo of 0.06.  Observations by the WISE
spacecraft suggest a somewhat smaller diameter of 1.7 km and a brighter optical albedo 
of 0.12 (Mainzer et al. 2011).  The differences in estimated diameters are 
consistent within their stated uncertainties, but they could also result from observations
obtained when the asteroid was at different orientations, and thus appear to have different 
diameters due to the elongated shape.

This asteroid will approach within 0.143 au on 2020 October 17 and we 
expect SNRs at Goldstone that should be strong enough for CW observations and ranging.
The SNRs at Arecibo will be strong enough for delay-Doppler imaging but it is not known
yet if Arecibo will be able to observe this asteroid due to a cable failure in August.
Observations at Goldstone are scheduled on October 15.  

1990 SP will be brighter than 17th magnitude from early September to late October, 2020, and will
be a good target for photometry.  New photometric observations would be particularly valuable 
because the rotation is slow and the spin state is not known precisely.  

The 2020 Earth flyby is the closest by this asteroid until 2031 when 1990 SP
will approach within 0.0985 au.


Orbital and Physical Characteristics  
Name                     1990 SP
Asteroid number          5645
Discoverer               R. H. McNaught/AANEAS
Discovery date           1990 Sep 20
orbit type               Apollo
Close approach distance  0.142 au  (55.3 lunar distances or 21 million km)
Close approach date      2020 Oct 17

semimajor axis           1.355 au
eccentricity             0.387
inclination              13.5 deg                 
Orbital period           1.58 years              
perihelion distance      0.830 au
aphelion distance        1.879 au                 
MOID                     0.0543 au

absolute magnitude (H)   17.1
diameter                 1.7 km                WISE: Mainzer et al. 2011
                         2.20 +0.74 -0.64 km   Spitzer: Mueller et al. 2011
optical albedo           0.12                  WISE: Mainzer et al. 2011
                         0.06 +0.079 -0.034    Spitzer: Mueller et al. 2011
rotation period          30.39 h               Pravec et al. 2005
lightcurve amplitude     0.7 mag               Pravec et al. 2005
pole direction           unknown                  
spectral class           Xe                    Lazzarin et al. 2004
PHA?                     No

Last update: 2020 October 19

Discovery M.P.E.C.


The discovery was probably announced in an IAU Circular in Sep. 1990.


SNR Calculations

Goldstone SNRs

(5645) 1990 SP:  D = 1.7 km,  P = 30.39 h,  OC albedo = 0.1

w  DOY   start date    window        RA, dec   dist   runs   SNR/day SNR/run
41  282  2020 Oct 08  09:33-16:36    97, -14  0.161    78       26      3
41  283  2020 Oct 09  09:37-16:47    99, -13  0.157    82       29      4
41  284  2020 Oct 10  09:41-16:58   102, -12  0.154    85       32      4
41  285  2020 Oct 11  09:45-17:10   105, -11  0.151    88       35      4
42  286  2020 Oct 12  09:49-17:23   108, -10  0.148    91       38      4 
42  287  2020 Oct 13  09:53-17:35   111,  -9  0.146    94       41      5 
42  288  2020 Oct 14  09:58-17:48   115,  -8  0.144    97       44      5 
42  289  2020 Oct 15  10:02-18:02   118,  -7  0.143   100       46      5 *  SCHEDULED
42  290  2020 Oct 16  10:07-18:15   121,  -5  0.142   102       48      5 
42  291  2020 Oct 17  10:12-18:29   124,  -4  0.142   104       49      5 
42  292  2020 Oct 18  10:17-18:42   128,  -3  0.142   106       49      5 
43  293  2020 Oct 19  10:22-18:55   131,  -2  0.143   107       49      5 
43  294  2020 Oct 20  10:27-19:08   134,   0  0.144   108       48      5 
43  295  2020 Oct 21  10:31-19:21   137,  +1  0.146   108       46      5 
43  296  2020 Oct 22  10:36-19:33   140,  +2  0.148   108       44      5 
43  297  2020 Oct 23  10:41-19:44   143,  +3  0.151   107       41      4 
43  298  2020 Oct 24  10:45-19:55   146,  +4  0.154   107       38      4   
43  299  2020 Oct 25  10:50-20:06   149,  +5  0.157   105       35      4
44  300  2020 Oct 26  10:54-20:15   152,  +6  0.161   104       32      3
44  301  2020 Oct 27  10:58-20:24   155,  +7  0.165   102       29      3

Goldstone has only one klystron and full power is not expected until Nov. 2020. 
The SNRs assume Ptx = 450 kW and are probably optimistic by about a factor of two.


1990 SP ARECIBO SNRs
 start date    window        RA, dec   dist    runs      SNR/day   SNR/run
2020 Oct 20  11:03-11:47    134,  -1  0.144      9        240        83
2020 Oct 21  10:59-12:09    137,  +1  0.146     14        330        93
2020 Oct 22  10:58-12:27    140,  +2  0.148     17        370        98
2020 Oct 23  11:00-12:41    143,  +3  0.150     20        400       100
2020 Oct 24  11:02-12:54    146,  +4  0.153     21        410        98
2020 Oct 25  11:06-13:06    149,  +5  0.157     23        400        91
2020 Oct 26  11:09-13:16    152,  +6  0.160     23        380        84
2020 Oct 27  11:13-13:26    154,  +7  0.165     24        350        76
2020 Oct 28  11:17-13:34    157,  +8  0.169     24        320        69
2020 Oct 29  11:20-13:42    159,  +9  0.174     24        290        63
2020 Oct 30  11:24-13:49    162,  +9  0.179     24        270        57
2020 Oct 31  11:28-13:55    164, +10  0.184     24        240        51
2020 Nov 01  11:31-14:01    166, +11  0.190     23        210        46
2020 Nov 02  11:34-14:06    168, +11  0.196     23        190        42
2020 Nov 03  11:37-14:11    170, +12  0.202     22        170        37
2020 Nov 04  11:40-14:15    172, +12  0.208     22        150        33
2020 Nov 05  11:43-14:19    173, +12  0.215     21        130        30
2020 Nov 06  11:45-14:22    175, +13  0.221     21        120        27
2020 Nov 07  11:47-14:25    177, +13  0.228     20        100        24
2020 Nov 08  11:49-14:27    178, +13  0.235     20         94        22
2020 Nov 09  11:51-14:30    180, +13  0.242     19         83        20
2020 Nov 10  11:52-14:32    181, +14  0.249     19         75        18
2020 Nov 11  11:54-14:33    183, +14  0.257     18         66        16
2020 Nov 12  11:55-14:35    184, +14  0.264     18         59        15
2020 Nov 13  11:56-14:36    185, +14  0.272     17         53        13
2020 Nov 14  11:57-14:37    186, +14  0.279     17         48        12

Arecibo SNRs assume Ptx = 700 kW, Tsys = 25 K, and D = 1.7 km.  The SNRs
will be weaker because the gain is about 30% lower than assumed here due to damage
sustained from Hurricane Maria in 2017.

Unfortunately, Arecibo will probably not be operational following a cable failure
in August, 2020.



Track Assignments


DOY  BOA   BOT   EOT   EOA
289  1310  1440  1800  1830      GSSR AST 1990 SP

Goldstone tracks:
     UT       UT          PDT               Duration Round-trip     
DOY  Date     TX Window   TX Window         hh:mm    time (sec)   SNR/run
289  Oct 15   1440-1800   0740-1100 Oct 15   3:20       143          3

The asteroid will be more than 20 degrees above the horizon by the time precal
starts, so we can begin observing as soon as we're ready, possibly as early as 13:40 UT
(06:40 PDT).  

SNR/run assumes ~1/2 power with only one klystron


Arecibo tracks:
UT                      UT          PST                Round-trip  
Date                    TX Window   TX Window          time (sec)  

...Not scheduled through at least November 4 due to the cable failure...



Uncertainties

1990 SP

The 3-sigma pointing and Doppler uncertainties are small.  We might not see a Doppler correction
to the ephemeris.

JPL/Horizons solution 136, # obs: 707 (1974-2020)
2020 October 12
 Date__(UT)__HR:MN     R.A._(a-appar)_DEC.            delta POS_3sigma  DOP_S_3sig  DOP_X_3sig  RT_delay_3sig
 2020-Oct-10 00:00 *   100.68741 -12.60288 0.15538941286467      0.406        0.38        1.40       0.000264
 2020-Oct-11 00:00 *   103.58887 -11.68697 0.15224567540910      0.412        0.40        1.44       0.000267
 2020-Oct-12 00:00 *   106.57897 -10.70395 0.14948585388491      0.417        0.41        1.48       0.000271
 2020-Oct-13 00:00 *   109.64860  -9.65690 0.14713245172491      0.422        0.42        1.51       0.000275
 2020-Oct-14 00:00 *   112.78655  -8.55086 0.14520648941426      0.426        0.42        1.54       0.000279
*2020-Oct-15 00:00 *m  115.97959  -7.39287 0.14372677688749      0.428        0.43        1.56       0.000283 *
 2020-Oct-16 00:00 *m  119.21278  -6.19186 0.14270919072490      0.429        0.43        1.57       0.000287
 2020-Oct-17 00:00 *m  122.46989  -4.95848 0.14216601092646      0.429        0.43        1.57       0.000291
 2020-Oct-18 00:00 *m  125.73390  -3.70472 0.14210537520447      0.429        0.43        1.57       0.000295
 2020-Oct-19 00:00 *m  128.98753  -2.44336 0.14253090503222      0.427        0.43        1.55       0.000299
 2020-Oct-20 00:00 *m  132.21390  -1.18745 0.14344154531959      0.424        0.42        1.54       0.000302

- - - - - - - - - - 

JPL/Horizons solution 130, # obs: 614 (1974-2020)
2020 September 11

 Date__(UT)__HR:MN     R.A._(a-appar)_DEC.            delta POS_3sigma  DOP_S_3sig  DOP_X_3sig  RT_delay_3sig
 2020-Oct-10 00:00 *   100.68741 -12.60290 0.15538939796082      0.644        0.54        1.96       0.000381
 2020-Oct-11 00:00 *   103.58887 -11.68699 0.15224565957314      0.647        0.55        2.00       0.000392
 2020-Oct-12 00:00 *   106.57897 -10.70397 0.14948583706613      0.647        0.56        2.04       0.000405
 2020-Oct-13 00:00 *   109.64860  -9.65692 0.14713243388191      0.644        0.57        2.06       0.000417
 2020-Oct-14 00:00 *   112.78655  -8.55088 0.14520647051678      0.639        0.57        2.07       0.000429
*2020-Oct-15 00:00 *m  115.97959  -7.39289 0.14372675691797      0.632        0.57        2.06       0.000442*
 2020-Oct-16 00:00 *m  119.21278  -6.19187 0.14270916967952      0.621        0.56        2.03       0.000454
 2020-Oct-17 00:00 *m  122.46989  -4.95850 0.14216598881564      0.609        0.55        1.99       0.000466
 2020-Oct-18 00:00 *m  125.73390  -3.70473 0.14210535205276      0.595        0.53        1.94       0.000477
 2020-Oct-19 00:00 *m  128.98753  -2.44337 0.14253088087747      0.580        0.52        1.88       0.000487
 2020-Oct-20 00:00 *m  132.21390  -1.18747 0.14344152021143      0.563        0.50        1.81       0.000497


Apparent Magnitudes, Solar Elongations, Lunar Elongations, and Lunar Illumination: Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta APmag S-brt S-O-T /r T-O-M/MN_Illu% 2020-Sep-20 00:00 62.05970 -20.00215 0.26873655578096 16.487 5.644 114.3623 /L 138.9/ 9.6396 2020-Sep-22 00:00 64.61133 -19.84398 0.25464438012801 16.387 5.646 113.3958 /L 141.1/ 27.5806 2020-Sep-24 00:00 67.36991 -19.61353 0.24097310416887 16.288 5.652 112.2502 /L 130.9/ 49.2564 2020-Sep-26 00:00 70.36539 -19.29470 0.22776775124763 16.193 5.661 110.9022 /L 115.9/ 69.9070 2020-Sep-28 00:00 73.63056 -18.86831 0.21508513678561 16.102 5.673 109.3256 /L 100.0/ 86.3174 2020-Sep-30 00:00 77.20037 -18.31174 0.20299688999867 16.018 5.690 107.4913 /L 84.7/ 96.5911 2020-Oct-02 00:00 81.11039 -17.59874 0.19159248599315 15.943 5.712 105.3685 /L 70.4/ 99.8140 2020-Oct-04 00:00 85.39408 -16.69999 0.18098204153907 15.881 5.739 102.9268 /L 57.7/ 95.9118 2020-Oct-06 00:00 90.07869 -15.58469 0.17129828162914 15.835 5.772 100.1398 /L 47.1/ 85.5219 2020-Oct-08 00:00 95.17933 -14.22401 0.16269662147107 15.812 5.813 96.9914 /L 39.8/ 69.8090 2020-Oct-10 00:00 100.69165 -12.59670 0.15535184746905 15.815 5.861 93.4838 /L 37.9/ 50.4120 2020-Oct-12 00:00 106.58422 -10.69699 0.14944968237104 15.851 5.916 89.6481 /L 43.2/ 29.7655 2020-Oct-14 00:00 112.79285 -8.54311 0.14517208201772 15.924 5.980 85.5528 /L 55.6/ 11.6832 2020-Oct-16 00:00 119.22011 -6.18335 0.14267692080539 16.038 6.051 81.3077 /L 73.3/ 1.2022 2020-Oct-18 00:00 125.74216 -3.69558 0.14207557278218 16.189 6.126 77.0565 /L 93.9/ 2.2607 2020-Oct-20 00:00 132.22293 -1.17787 0.14341444964682 16.374 6.203 72.9584 /L 115.6/ 14.5491 2020-Oct-22 00:00 138.53182 1.26789 0.14666694812410 16.583 6.279 69.1617 /L 136.8/ 33.7294 2020-Oct-24 00:00 144.55975 3.55350 0.15173912000370 16.804 6.347 65.7799 /L 156.4/ 54.7096

Setups



Due the 30.4 h rotation period and a diameter of roughly 1.7 km, we are expecting a bandwidth
of about 6 Hz.  The shape appears elongated so the bandwidth could vary considerably as
the asteroid spins.

CW setup:
---------------------------------------------------------------------------
TX polarization           RCP
RCV polarization          LCP & RCP
Frequency hops:           no hopping
Bandwidth:               5000 Hz 
TXoffset                 +500 Hz
FFT                      5000 for 1.0 Hz resolution 

Ranging setups:
---------------------------------------------------------------------------
10-usec
baud             10 usec
code            127
PRP            1270 usec
ncoh              1 
bandwidth       787 Hz   
FFT             128
resolution       6.15 Hz
TXoffset       +100 Hz  (echo in column 80)
---------------------------------------------------------------------------
11-usec 
baud             11 usec
code            127
PRP            1397 usec
ncoh              1 
bandwidth       716 Hz   
FFT             128
resolution      5.6 Hz
TXoffset     +100 Hz  (echo in column 82) 
-------------------------------------------------------------------------
1-usec 
baud              1 usec
code            255
ncoh              8
bandwidth       245 Hz   
FFT             128
resolution        3.8 Hz
TXoffset        +50 Hz  (echo in column 116)
---------------------------------------------------------------------

Instructions

NOTE: Data should be moved to the appropriate subdirectories in aardvark:/export/data0/1990sp/raw/

POINTING:

  OSOD and predicts are on aardvark:
/export/data3/osod/ops/a5645/EPH.OUT.s136
/export/data3/osod/ops/a5645/PRDX.OUT.14f-14-14.s136
/export/data3/osod/ops/a5645/PRDX.OUT.14v-14-14.s136
/export/data3/osod/ops/a5645/PUNCH.OUT.14f-14-14.s136
/export/data3/osod/ops/a5645/PUNCH.OUT.14v-14-14.s136


POINTING  
1990 SP DSS-14 Pointing
                                            TX Offsets
Date (UTC)  DOY  hhmmss  RA        Dec      LHA   Dec   RTT   OSOD
2020 OCT 15 289  130000  117.7378 -6.7500  -7.9   2.0   142.8  136
2020 OCT 15 289  140000  117.8690 -6.6999  -7.7   2.0   142.7
2020 OCT 15 289  150000  118.0003 -6.6496  -6.2   2.0   142.7
2020 OCT 15 289  160000  118.1319 -6.5991  -4.4   2.0   142.7
2020 OCT 15 289  170000  118.2640 -6.5485  -3.0   2.0   142.6
2020 OCT 15 289  180000  118.3968 -6.4978  -2.1   2.1   142.6

Transmit offsets are given in millidegrees.  


PRDX.OUT.14f-14-14.s136 TRANSMITTER: STATION #14, RECEIVER: STATION #14 RECEIVER U.T. RANGE DOPPLER LHA DEC RA EL 2020 OCT 15 13:00 142.7819680433 104342.349 158.3297 -6.7500 117.7378 45.4883 104342.349 0.0000000026 2020 OCT 15 13:10 142.7746969960 103123.179 161.7268 -6.7417 117.7597 46.1881 103123.179 0.0000000013 2020 OCT 15 13:20 142.7675117331 101894.932 165.2090 -6.7333 117.7815 46.7726 101894.932 0.0000000011 2020 OCT 15 13:30 142.7604128310 100659.313 168.7636 -6.7250 117.8034 47.2369 100659.313 0.0000000008 2020 OCT 15 13:40 142.7534007466 99418.038 172.3757 -6.7166 117.8253 47.5770 99418.038 0.0000000010 2020 OCT 15 13:50 142.7464758157 98172.836 176.0282 -6.7082 117.8472 47.7900 98172.836 0.0000000018 2020 OCT 15 14:00 142.7396382496 96925.442 179.7028 -6.6999 117.8690 47.8738 96925.442 -0.0000000001 2020 OCT 15 14:10 142.7328881442 95677.595 183.3803 -6.6915 117.8909 47.8276 95677.595 -0.0000000014 2020 OCT 15 14:20 142.7262254737 94431.037 187.0414 -6.6831 117.9128 47.6520 94431.037 0.0000000008 2020 OCT 15 14:30 142.7196500767 93187.504 190.6673 -6.6748 117.9346 47.3486 93187.504 -0.0000000026 2020 OCT 15 14:40 142.7131616938 91948.729 194.2407 -6.6664 117.9565 46.9201 91948.729 0.0000000009 2020 OCT 15 14:50 142.7067599177 90716.434 197.7459 -6.6580 117.9784 46.3702 90716.434 -0.0000000016 2020 OCT 15 15:00 142.7004442407 89492.331 201.1697 -6.6496 118.0003 45.7036 89492.331 -0.0000000035 2020 OCT 15 15:10 142.6942140357 88278.115 204.5011 -6.6412 118.0222 44.9256 88278.115 0.0000000013 2020 OCT 15 15:20 142.6880685376 87075.462 207.7317 -6.6328 118.0441 44.0419 87075.462 0.0000000005 2020 OCT 15 15:30 142.6820068841 85886.027 210.8559 -6.6244 118.0660 43.0587 85886.027 -0.0000000001 2020 OCT 15 15:40 142.6760280916 84711.439 213.8700 -6.6160 118.0880 41.9822 84711.439 -0.0000000007 2020 OCT 15 15:50 142.6701310629 83553.301 216.7725 -6.6075 118.1099 40.8188 83553.301 -0.0000000013 2020 OCT 15 16:00 142.6643145895 82413.182 219.5639 -6.5991 118.1319 39.5746 82413.182 -0.0000000015 2020 OCT 15 16:10 142.6585773545 81292.620 222.2459 -6.5907 118.1539 38.2558 81292.620 -0.0000000023 2020 OCT 15 16:20 142.6529179339 80193.115 224.8214 -6.5823 118.1758 36.8679 80193.115 -0.0000000030 2020 OCT 15 16:30 142.6473348071 79116.125 227.2943 -6.5738 118.1979 35.4167 79116.125 0.0000000024 2020 OCT 15 16:40 142.6418263324 78063.068 229.6692 -6.5654 118.2199 33.9072 78063.068 0.0000000001 2020 OCT 15 16:50 142.6363907905 77035.318 231.9511 -6.5570 118.2419 32.3444 77035.318 -0.0000000026 2020 OCT 15 17:00 142.6310263674 76034.197 234.1451 -6.5485 118.2640 30.7326 76034.197 0.0000000007 2020 OCT 15 17:10 142.6257311379 75060.981 236.2567 -6.5401 118.2861 29.0762 75060.981 -0.0000000041 2020 OCT 15 17:20 142.6205031162 74116.892 238.2914 -6.5316 118.3081 27.3789 74116.892 -0.0000000030 2020 OCT 15 17:30 142.6153402128 73203.095 240.2546 -6.5231 118.3303 25.6445 73203.095 -0.0000000033 2020 OCT 15 17:40 142.6102402648 72320.701 242.1516 -6.5147 118.3524 23.8760 72320.701 -0.0000000048 2020 OCT 15 17:50 142.6052010405 71470.759 243.9875 -6.5062 118.3746 22.0767 71470.759 -0.0000000013 2020 OCT 15 18:00 142.6002202232 70654.260 245.7675 -6.4978 118.3968 20.2492 70654.260 0.0000000006

(5645) 1990 SP GOLDSTONE MASTERLOG

Receive Setup code ncoh FFT runs start -stop OSOD offset CW, no hops - - 25000 11 145009-154312 136 +500 Hz Ptx = 260 kW Stopped early due to a high voltage problem.
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 https://echo.jpl.nasa.gov/asteroids/1990SP/1990sp.2020.planning.html

Asteroid Radar Astronomy
*************************************************************************************************************