Goldstone Radar Observations Planning: 2005 UL5
Delay-Doppler images of 2005 UL5 obtained on Nov. 20, 2015 using DSS-14 to transmit and Green Bank to receive. Resolution is 3.75 m x 0.1 Hz, but we double sampled, so each pixel covers 1.875 m in range. Range increases down and Doppler frequency increases to the right. The images span an interval of about 1 hour and 10 minutes. The asteroid has approximate pole-on dimensions of 200 x 300 m. The images reveal a rounded, somewhat asymmetric object with a modest number of radar-dark and radar-bright features. The clump of bright pixels on the lower left edge in the early frames likely corresponds to a decameter-sized boulder. The rotation of the object is consistent with the 3.5 h period estimated from lightcurves. although the data are too sparse to provide a definite confirmation.
Delay-Doppler images of 2005 UL5 obtained on Nov. 21, 2015 using DSS-14 to transmit and Green Bank to receive. The resolution is 3.75 m x 0.1 Hz. The sequence appears to continue from the last frame from Nov. 20. This collage spans about 1.5 hours.
2005 UL5 was discovered in November 2005 by LINEAR. This object has an absolute magnitude of 20.2, suggesting a diameter of roughly 300 m, and spectroscopy reported by Binzel et al. 2006 indicates an Sq-classification. Recent lightcurves reported in November 2015 by P. Pravec, T. Lister, and S. Greenstreet yielded a rotation period of 6.9 h with an amplitude of 0.25 magnitude. This suggests that the elongation is modest. Even more recent photometry has since suggested that this object shows evidence for two rotation periods and thus that it is a non-principal axis rotator. The longer period is about 5 hours (P. Pravec, pers. comm.) If the NPA spin state is correct, then the bandwidth variations during the Goldstone observations with this object could be considerable. J. Richardson et al. detected radar echoes from 2005 UL5 at Arecibo on Nov. 16, updated the orbit, and estimated radar cross sections and the bandwidth. They obtained a bandwidth of 1.1 Hz, SC/OC = 0.29, and OCxsec = 3.85E-3 km^2. The bandwidth and rotation state place a lower bound on its maximum pole-on dimension of about 200 meters. If we adopt 200 m as the diameter, then that implies that the SNRs shown below are too large by about a factor of two. Even so, this object is still a strong radar target at Goldstone. This asteroid will approach within 0.0153 au on November 20 and it will probably be one of the strongest radar targets of the year. The SNRs should be high enough for imaging at a resolution of 3.75 m/pixel at DSS-14. We plan to observe 2005 UL5 at Goldstone, Arecibo, Green Bank, and as a proof-of-concept bistatic target at DSS-43 and Parkes (Australia). The Minor Planet Center has classified 2005 UL5 as a "Potentially Hazardous Asteroid."
Orbital and Physical Characteristics
Provisional Designation 2005 UL5
Asteroid number 413577
Discoverer LINEAR
Discovery date 2005 Oct 27
orbit type Aten
Close approach date 2015 Nov 20
Close approach dist. 0.0153 au
Close approach dist. 5.95 lunar distances
semimajor axis 0.937 au
eccentricity 0.570
inclination 14.3 deg
perihelion distance 0.403 au
aphelion distance 1.471 au
Tisserand parameter
absolute magnitude (H) 20.2
diameter 0.3 km +- a factor of two
optical albedo unknown
rotation period 6.9 h Pravec, Lister, Greenstreet et al., pers. comm.
lightcurve amplitude ~0.25
pole direction unknown
spectral class Sq Binzel et al. 2006
This asteroid makes relatively frequent close approaches to Earth, Venus, and Mercury.
Here are encounters through the end of the century:
Date (CT) Body CA Dist MinDist MaxDist Vrel TCA3Sg Nsigs P_i/p
A.D. 2015 Nov 20.17627 Earth .015280 .015278 .015282 18.993 0.11 65530. .000000
A.D. 2026 Nov 29.68745 Merc .055943 .055936 .055951 18.884 1.52 4.99E5 .000000
A.D. 2030 Jul 25.05419 Merc .024865 .024856 .024874 16.365 3.48 94819. .000000
A.D. 2034 Mar 13.95935 Merc .053825 .053805 .053846 23.913 1.83 1.07E5 .000000
A.D. 2038 Aug 05.49980 Venus .087867 .087855 .087880 19.026 1.01 4.94E5 .000000
A.D. 2044 Nov 17.91105 Earth .069093 .069073 .069114 20.588 0.97 54215. .000000
A.D. 2045 Dec 08.45466 Merc .062573 .062551 .062596 20.171 2.97 4.91E5 .000000
A.D. 2049 Aug 01.73127 Merc .030553 .030540 .030566 15.876 6.52 11359. .000000
A.D. 2053 Mar 22.47458 Merc .039467 .039442 .039492 22.326 2.74 1.20E5 .000000
A.D. 2055 Oct 23.76455 Venus .082953 .082942 .082965 23.576 1.13 4.59E5 .000000
A.D. 2063 Nov 22.00362 Earth .055436 .055423 .055449 17.074 0.32 50964. .000000
A.D. 2068 Aug 05.50881 Merc .040768 .040765 .040770 15.611 2.75 3.25E5 .000000
A.D. 2072 Mar 30.41498 Merc .022523 .022519 .022528 20.283 0.64 1.43E5 .000000
A.D. 2083 Dec 26.79584 Merc .091217 .091199 .091236 24.652 0.99 5.06E5 .000000
A.D. 2087 Aug 18.73649 Merc .036915 .036909 .036922 15.540 5.57 1.68E5 .000000
A.D. 2088 Jun 03.86169 Venus .082205 .082194 .082217 19.552 1.03 4.92E5 .000000
A.D. 2091 Apr 11.30494 Merc .036449 .036423 .036474 21.929 3.10 1.20E5 .000000
A.D. 2092 Nov 20.92543 Earth .031275 .031251 .031299 17.734 0.75 44005. .000000
Last update: 2015 November 24
2005 UL5 http://www.minorplanetcenter.org/mpec/K05/K05U79.html
Goldstone SNRs
Assumptions: D = 0.32 km, P = 6.9 h, OC radar albedo = 0.1
<--MONOSTATIC--> DSS14/GBT DSS14/AO DSS13/AO DSS13/GBT
w DOY start date window RA, dec dist runs SNR/day SNR/run SNR/RTT SNR/RTT SNR/RTT SNR/RTT
46 317 2015 Nov 13 05:59-14:56 92, +2 0.075 213 26 2
46 318 2015 Nov 14 06:04-14:59 94, +2 0.065 247 48 3 20
46 319 2015 Nov 15 06:12-15:04 97, +1 0.054 294 98 6 40
47 320 2015 Nov 16 06:25-15:15 101, 0 0.044 361 230 13 26 87
47 321 2015 Nov 17 06:49-15:35 107, -1 0.033 464 660 33 66 220
47 322 2015 Nov 18 07:36-16:17 120, -4 0.024 627 2400 110 * 220 ---
47 323 2015 Nov 19 09:21-17:53 146, -8 0.017 839 9800 370 740 --- -- 37
47 324 2015 Nov 20 12:29-20:33 190, -12 0.016 805 10000 400 * 800 * --- -- 40
47 325 2015 Nov 21 14:32-22:19 220, -11 0.023 577 2500 110 * 220 * --- --
47 326 2015 Nov 22 15:21-23:09 233, -9 0.033 421 660 35 70 ---
48 327 2015 Nov 23 15:44-23:34 240, -8 0.043 326 220 14 32 ---
48 328 2015 Nov 24 15:55-23:48 244, -8 0.053 264 94 6
48 329 2015 Nov 25 16:01-23:56 247, -7 0.064 221 45 3
48 330 2015 Nov 26 16:05-00:01 249, -7 0.075 190 24 2
** Note added 2015 Nov 18: With recent information from Arecibo and the spin state, we
** are expecting SNRs about 1/2 as strong as shown here.
Bistatic observations with Arecibo are possible only through Nov. 17. Afterward the asteroid
will move too far south. Due to the schedules, bistatic Goldstone/Arecibo observations will
not occur with 2005 UL5.
The SNRs will probably be too weak for bistatic DSS-13/Green Bank observations.
Goldstone SNRs assume Ptx = 450 kW.
DSS-43/Parkes SNRs
start date window RA, dec dist SNR/RTT
2015 Nov 18 1440-2235 125, -4 0.023 2
2015 Nov 19-20 1615-0115 157, -10 0.016 8 * Scheduled
2015 Nov 20-21 1900-0355 200, -12 0.018 10
2015 Nov 21-22 2050-0510 224, -10 0.026 2 * Scheduled
The DSS-43/Parkes SNRs assume that Ptx = 100 kW.
Horizons at Parkes = 30 deg. Horizons at DSS-43 = 20 deg.
** Note added 2015 Nov 18: With recent information from Arecibo and the spin state, we
** are expecting SNRs about 1/2 as strong as shown here.
Arecibo SNRs
start date window RA, dec dist runs SNR/day SNR/run
2015 Nov 05 06:17-08:06 85, +4 0.165 20 12 3
2015 Nov 06 06:15-08:04 86, +4 0.154 21 15 4
2015 Nov 07 06:14-08:01 86, +4 0.143 22 21 5
2015 Nov 08 06:13-07:59 87, +4 0.132 24 28 6
2015 Nov 09 06:13-07:57 87, +3 0.121 26 40 9
2015 Nov 10 06:13-07:55 88, +3 0.110 28 57 12
2015 Nov 11 06:13-07:54 89, +3 0.099 30 84 17
2015 Nov 12 06:15-07:54 90, +3 0.088 33 130 25
2015 Nov 13 06:19-07:54 92, +2 0.077 37 210 39
2015 Nov 14 06:25-07:55 94, +2 0.066 40 370 65
2015 Nov 15 06:35-07:58 96, +1 0.056 45 700 110
2015 Nov 16 06:52-08:03 100, +1 0.045 47 1400 220 * Scheduled
2015 Nov 17 07:27-08:09 106, -1 0.035 36 2700 460 * Scheduled
Assumptions: Ptx = 900 kW, Tsys = 23 K, P = 6.9 h
Track Assignments
DOY BOA BOT EOT EOA Site
322 0610 0740 1100 1130 DSS-14 GSSR AST 2005 UL5
323 1715 1800 2200 2220 DSS-43 GSSR AST 2005 UL5 DSS-43/Parkes
324 1100 1230 1415 1445 DSS-14 GSSR AST 2005 UL5 Also: Green Bank
325 1355 1525 1720 1750 DSS-14 GSSR AST 2005 UL5 Also: Green Bank
326 0030 0115 0505 0525 DSS-43 GSSR AST 2005 UL5 DSS-43/Parkes
Schedule for ALL Radar Tracks at DSS-14, Arecibo, Green Bank, DSS-43, and Parkes:
UT UT PST Round-trip
Observatory DOY Date TX Window TX Window time (sec) SNR/RTT
Arecibo 320 Nov 16 0652-0803 2252-0003 Nov 15-16 45 220
Arecibo 321 Nov 17 0727-0809 2307-0009 Nov 16-17 35 460
DSS-14 322 Nov 18 0735-1100 2335-0300 Nov 17-18 24 100
DSS-43/Parkes 323 Nov 19 1800-2200 1000-1400 Nov 19 16 8 Bistatic SNR
DSS-14/GBT 324 Nov 20 1230-1415 0430-0615 Nov 20 16 400
DSS-14/GBT 325 Nov 21 1435-1720 0635-0920 Nov 21 23 110
DSS-43/Parkes 326 Nov 22 0115-0505 1715-2105 Nov 21 26 2 Bistatic SNR
Uncertainties
JPL/Horizons solution 45, # obs: 194 (2005-2015):
Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta POS_3sigma DOP_S_3sig DOP_X_3sig RT_delay_3sig
2015-Nov-11 00:00 *m 88.92343 3.04268 0.10200943140323 0.909 0.32 1.17 0.000349
2015-Nov-12 00:00 *m 90.00577 2.80379 0.09110357653553 1.036 0.34 1.25 0.000351
2015-Nov-13 00:00 *m 91.35526 2.50916 0.08025615905268 1.199 0.39 1.40 0.000353
2015-Nov-14 00:00 *m 93.09766 2.13187 0.06948258582638 1.415 0.46 1.67 0.000354
2015-Nov-15 00:00 *m 95.44743 1.62564 0.05881076112837 1.710 0.60 2.19 0.000354
2015-Nov-16 00:00 *m 98.79936 0.90514 0.04829477899424 2.138 0.88 3.20 0.000351
2015-Nov-17 00:00 *m 103.95335 -0.20122 0.03805006046785 2.799 1.45 5.28 0.000346
2015-Nov-18 00:00 *m 112.72851 -2.06789 0.02835791901100 3.890 2.73 9.92 0.000336
2015-Nov-19 00:00 *m 129.63020 -5.46813 0.02002453609069 5.663 5.66 20.59 0.000331
2015-Nov-20 00:00 *m 162.49770 -10.42009 0.01542979162800 6.939 8.79 31.96 0.000395
2015-Nov-21 00:00 *m 201.00049 -11.93167 0.01776682197137 5.221 5.32 19.34 0.000488
2015-Nov-22 00:00 *m 223.43964 -10.42805 0.02518552957478 3.646 2.53 9.19 0.000507
2015-Nov-23 00:00 *m 234.65486 -9.07111 0.03456959851753 2.760 1.38 5.01 0.000508
2015-Nov-24 00:00 *m 240.90482 -8.16641 0.04471482070849 2.213 0.85 3.10 0.000509
2015-Nov-25 00:00 * 244.79560 -7.56139 0.05522161111912 1.847 0.60 2.16 0.000512
2015-Nov-26 00:00 * 247.42274 -7.14267 0.06593699166104 1.587 0.47 1.69 0.000517
2015-Nov-27 00:00 * 249.30355 -6.84455 0.07679439677283 1.394 0.40 1.47 0.000524
2015-Nov-28 00:00 * 250.70934 -6.62882 0.08776279212163 1.246 0.38 1.37 0.000532
2015-Nov-29 00:00 * 251.79487 -6.47231 0.09882781892294 1.127 0.37 1.35 0.000542
2015-Nov-30 00:00 * 252.65455 -6.36038 0.10998384490133 1.031 0.37 1.36 0.000552
- - - - - - - - - - -
JPL/Horizons solution 35, # obs: 147 (2005-2014):
Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta POS_3sigma DOP_S_3sig DOP_X_3sig RT_delay_3sig
2015-Nov-11 00:00 *m 88.92343 3.04268 0.10200945366361 4.916 0.72 2.60 0.000377
2015-Nov-12 00:00 *m 90.00577 2.80379 0.09110359864452 5.563 0.96 3.51 0.000371
2015-Nov-13 00:00 *m 91.35526 2.50917 0.08025618094802 6.383 1.34 4.87 0.000364
2015-Nov-14 00:00 *m 93.09765 2.13187 0.06948260740773 7.451 1.92 6.99 0.000358
2015-Nov-15 00:00 *m 95.44742 1.62565 0.05881078222536 8.892 2.86 10.40 0.000361
2015-Nov-16 00:00 *m 98.79934 0.90514 0.04829479929566 10.920 4.47 16.25 0.000393
2015-Nov-17 00:00 *m 103.95332 -0.20121 0.03805007934489 13.898 7.46 27.12 0.000503
2015-Nov-18 00:00 *m 112.72847 -2.06787 0.02835793501119 18.330 13.43 48.83 0.000783
2015-Nov-19 00:00 *m 129.63014 -5.46811 0.02002454539619 23.478 24.10 87.59 0.001380
2015-Nov-20 00:00 *m 162.49761 -10.42007 0.01542978615631 19.620 21.54 78.29 0.002253
2015-Nov-21 00:00 *m 201.00044 -11.93167 0.01776680175955 14.105 9.24 33.60 0.002430
2015-Nov-22 00:00 *m 223.43962 -10.42805 0.02518550423133 14.600 9.62 34.96 0.002089
2015-Nov-23 00:00 *m 234.65485 -9.07111 0.03456957182695 12.493 5.93 21.54 0.001824
2015-Nov-24 00:00 *m 240.90482 -8.16640 0.04471479358045 10.427 3.50 12.71 0.001664
2015-Nov-25 00:00 * 244.79560 -7.56139 0.05522158377272 8.826 2.06 7.50 0.001571
2015-Nov-26 00:00 * 247.42275 -7.14267 0.06593696413794 7.613 1.20 4.34 0.001517
2015-Nov-27 00:00 * 249.30355 -6.84455 0.07679436906298 6.680 0.66 2.41 0.001489
2015-Nov-28 00:00 * 250.70934 -6.62882 0.08776276419891 5.945 0.40 1.46 0.001478
2015-Nov-29 00:00 * 251.79488 -6.47231 0.09882779075628 5.353 0.41 1.49 0.001480
2015-Nov-30 00:00 * 252.65455 -6.36038 0.10998381645840 4.868 0.54 1.98 0.001491
**********************************************************************************************
Apparent Magnitudes, Solar Elongations, Lunar Elongations, and Lunar Illumination:
Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta APmag S-O-T /r T-O-M/Illu%
2015-Nov-01 00:00 83.51130 4.32071 0.21329732880898 18.72 132.0435 /L 20.3/ 74.9
2015-Nov-02 00:00 83.86456 4.23344 0.20200070450669 18.59 132.5787 /L 30.8/ 65.2
2015-Nov-03 00:00 84.23759 4.14174 0.19073947691487 18.45 133.0912 /L 42.1/ 55.3
2015-Nov-04 00:00 84.63502 4.04473 0.17951384597183 18.30 133.5766 /L 53.4/ 45.4
2015-Nov-05 00:00 85.06274 3.94132 0.16832407149562 18.14 134.0287 /L 64.6/ 35.9
2015-Nov-06 00:00 85.52829 3.83004 0.15717051331607 17.98 134.4401 /L 75.7/ 27.0
2015-Nov-07 00:00 86.04151 3.70897 0.14605370114200 17.80 134.8010 /L 86.7/ 19.1
2015-Nov-08 00:00 86.61545 3.57552 0.13497444746046 17.62 135.0984 /L 97.5/ 12.3
2015-Nov-09 00:00 87.26775 3.42614 0.12393402727417 17.42 135.3148 /L 108.3/ 6.8
2015-Nov-10 00:00 88.02285 3.25583 0.11293446808992 17.21 135.4261 /L 119.0/ 2.9
2015-Nov-11 00:00 88.91553 3.05742 0.10197903140532 16.98 135.3980 /L 129.5/ 0.6
2015-Nov-12 00:00 89.99695 2.82022 0.09107304396180 16.74 135.1800 /L 139.7/ 0.2
2015-Nov-13 00:00 91.34539 2.52770 0.08022540419641 16.47 134.6947 /L 149.2/ 1.7
2015-Nov-14 00:00 93.08659 2.15312 0.06945148046417 16.17 133.8174 /L 157.4/ 5.2
2015-Nov-15 00:00 95.43510 1.65049 0.05877911815662 15.84 132.3351 /L 162.4/ 10.6
2015-Nov-16 00:00 98.78592 0.93493 0.04826232112653 15.47 129.8539 /L 162.5/ 17.7
2015-Nov-17 00:00 103.93992 -0.16435 0.03801638488976 15.06 125.5726 /L 159.0/ 26.4
2015-Nov-18 00:00 112.71983 -2.02071 0.02832256162835 14.64 117.6655 /L 156.0/ 36.3
2015-Nov-19 00:00 129.64555 -5.40737 0.01998799644936 14.38 101.6485 /L 158.1/ 47.1
2015-Nov-20 00:00 162.58345 -10.34786 0.01539943096326 15.21 70.1626 /L 161.8/ 58.3
2015-Nov-21 00:00 201.11273 -11.85877 0.01775481564799 19. 34.5080 /L 146.9/ 69.3
2015-Nov-22 00:00 223.51891 -10.37063 0.02518683654270 24. 16.2861 /L 140.8/ 79.4
2015-Nov-23 00:00 234.70971 -9.02778 0.03457741263014 28. 11.6899 /L 144.6/ 88.1
2015-Nov-24 00:00 240.94554 -8.13253 0.04472596084630 28. 12.4073 /T 152.7/ 94.6
2015-Nov-25 00:00 244.82768 -7.53387 0.05523458850920 27. 13.8103 /T 162.4/ 98.6
2015-Nov-26 00:00 247.44916 -7.11961 0.06595102547178 27. 14.9193 /T 169.7/ 99.8
2015-Nov-27 00:00 249.32601 -6.82477 0.07680903296846 27. 15.6838 /T 166.0/ 98.3
2015-Nov-28 00:00 250.72889 -6.61153 0.08777774407497 27. 16.1809 /T 155.5/ 94.3
2015-Nov-29 00:00 251.81221 -6.45697 0.09884289349596 27. 16.4848 /T 143.8/ 88.3
2015-Nov-30 00:00 252.67014 -6.34661 0.10999890491449 27. 16.6520 /T 131.9/ 80.7
Setups
Although most of the key physical properties are unknown, the Sq spectral class suggests that
the diameter is close to 0.3 km. If we assume that the rotation period is slower than 2.2 h,
which is true for the vast majority of NEAs for which periods are available, then the bandwidth
at X-band is likely to be no more than about 14 Hz. If we convert this to S-band, then
we get a rough upper bound of 4 Hz.
We're going to start with a standard CW setup, which should work fine:
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: 4000 for 1.0 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 +100 Hz (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/data0/2005ul5/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
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/2005UL5/2005UL5_planning.html
Asteroid Radar Astronomy