Goldstone Radar Observations Planning: 2017 TS3


Background


2017 TS3
2017 TS3 was discovered in October, 2017 by Pan-STARRS 1.  The absolute magnitude is 22.1,
suggesting a diameter of roughly 120 meters, but otherwise nothing is known about
its physical properties. 

This asteroid will approach within about 0.036 au on November 2.
Tracks are scheduled at Goldstone on November 1 and 2.
We are expecting SNRs strong enough for CW and ranging observations but probably
not detailed delay-Doppler imaging.

Orbital uncertainties for this asteroid are relatively large so we request optical astrometry.
The asteroid could be recovered as soon as the second or third week of September 
when the brightness reaches about magnitude 21, while solar elongations are favorable,
the solution 22 3-sigma pointing uncertainties are below 3000 arcsec, and before the Moon becomes full. 
By mid-October the 3-sigma pointing uncertainties will increase to ~7000 arcsec.

2021 Sep 29 Update: This object has been recovered and orbital uncertainties
with solution 24 are small.

2021 Oct 18 Update: J. Chatelain and T. Lister report a rotation period of 34.7 h and a lightcurve
amplitude of 0.5 mag.  All else being equal, this suggests that SNRs will be about 4x stronger
than previously guessed.   The lightcurve amplitude may imply a moderate degree of elongation.
If the diameter is close to 0.12 km, then the bandwidth at Goldstone could be ~0.35 Hz for an
equatorial view.


Orbital and Physical Characteristics  
Name                     2017 TS3
Asteroid number          not numbered
Discoverer               Pan-STARRS 1      
Discovery date           2017 Oct 10
Orbit type               Apollo
Close approach distance  0.0355 au 
Close approach distance  13.8 LD        
Close approach date      2021 Nov 2    

Semimajor axis           2.498 au       
Eccentricity             0.618          
Inclination              4.9 deg       
Orbital period           3.95 years     
Perihelion distance      0.954 au       
Aphelion distance        4.042 au
MOID                     0.026 au       

Absolute magnitude (H)   22.1
Diameter                ~0.12 km        
Optical albedo           unknown        
Rotation period          34.7 h   Chatelain and Lister (pers. comm.)
Lightcurve amplitude     0.5 mag  Chatelain and Lister (pers. comm.)
Spectral class           unknown        
PHA?                     No             

Last update: 2021 November 2


Goldstone Radar Echo from Asteroid 2017 TS3


Echo power spectrum obtained on November 1.


Discovery M.P.E.C.


2017 TS3
https://www.minorplanetcenter.net/mpec/K17/K17T68.html


SNR Calculations

Goldstone SNRs
2017 TS3

2017 TS3:  D = 0.12 km,  P = 34.7 h,  OC albedo = 0.1

DOY      start date       window       RA, dec   dist   runs      SNR/day   SNR/run
298-299 2021 Oct 25-26  22:23-12:37   359, +55  0.053    480         59         3
299-300 2021 Oct 26-27  22:09-13:12     2, +59  0.049    547         83         4
300-301 2021 Oct 27-28  21:51-14:10     6, +64  0.045    637        120         5
301-302 2021 Oct 28-29  21:25-16:16    14, +70  0.042    774        170         7
302-303 2021 Oct 29-30  20:27-17:31    30, +75  0.039   1100        240         8
303-304 2021 Oct 30-31  22:21-21:36    67, +79  0.037   1164        300        10
305     2021 Nov  1     01:29-23:37   113, +76  0.036   1202        340        11  Scheduled 1130-1300
306     2021 Nov  2     03:50-22:27   134, +69  0.036    884        310        12  Scheduled 0515-0645
307     2021 Nov  3     06:27-21:57   143, +61  0.037    745        270        11
308     2021 Nov  4     07:37-21:36   149, +53  0.038    650        210         9
309     2021 Nov  5     08:18-21:19   152, +46  0.041    571        160         7
310     2021 Nov  6     08:46-21:05   154, +39  0.044    505        120         6
311     2021 Nov  7     09:05-20:52   156, +34  0.047    448         85         4

Horizons were set at 20 deg except on two days when they were set at 25 deg
to make the asteroid appear to set. 

We could start early on both days if we're ready. 


Track Assignments


DOY    BOA   BOT   EOT   EOA
305    1000  1130  1300  1330  GSSR AST 2017 TS3
306    0345  0515  0645  0715  GSSR AST 2017 TS3

Goldstone tracks:
        UT        UT         PST                 Duration Round-trip     
DOY     Date      TX Window  TX Window           hh:mm    time (sec)   SNR/run 
305     Nov  1    1130-1300  0330-0500 Nov  1     1:30       36          11 
306     Nov  2    0515-0645  2215-2345 Nov  1     1:30       36          12 

Due to the 34.7 h rotation period, Goldstone observations will see
longitudes separated by about 184 degrees. 

Tracks 90 minutes in duration will cover about 15 degrees of rotation.


Uncertainties

2017 TS3
JPL/Horizons solution 38, # obs: 193 (2017-2021)
2021 Oct 28
 Date__(UT)__HR:MN     R.A._(a-appar)_DEC.             delta  POS_3sigma   DOP_X_3sig  RT_delay_3sig
 2021-Oct-25 00:00 *   355.99795  49.97603  0.05888959215500       0.431         0.68       0.000177
 2021-Oct-26 00:00 *   357.64141  53.51447  0.05442183931422       0.486         0.80       0.000175
 2021-Oct-27 00:00 *   359.98735  57.61016  0.05022219874671       0.553         0.97       0.000172
 2021-Oct-28 00:00 *     3.54852  62.32706  0.04635826193177       0.636         1.20       0.000168
 2021-Oct-29 00:00 *     9.46457  67.66214  0.04291568223764       0.735         1.51       0.000162
 2021-Oct-30 00:00 *    20.68558  73.38083  0.03999849552623       0.849         1.88       0.000153
 2021-Oct-31 00:00 *    45.42220  78.39021  0.03772409280850       0.970         2.30       0.000142
 2021-Nov-01 00:00 *    90.28521  79.20754  0.03620934518431       1.083         2.70       0.000129 Scheduled
 2021-Nov-02 00:00 *   123.43138  74.04006  0.03554730432054       1.169         2.99       0.000116 Scheduled
 2021-Nov-03 00:00 *   138.35892  66.35216  0.03578143650091       1.212         3.10       0.000105
 2021-Nov-04 00:00 *m  145.78780  58.24237  0.03689110611563       1.208         3.00       0.000100
We're expecting a bandwidth of ~0.35 Hz so there could be a visible Doppler correction.

JPL/Horizons solution 24, # obs: 95 (2017-2021)
2021 Sep 29
 Date__(UT)__HR:MN     R.A._(a-appar)_DEC.            delta POS_3sigma  DOP_X_3sig  RT_delay_3sig
 2021-Oct-25 00:00 *   355.99796  49.97601 0.05888959233433      1.683        2.40       0.000322
 2021-Oct-26 00:00 *   357.64142  53.51445 0.05442183840042      1.878        2.97       0.000304
 2021-Oct-27 00:00 *   359.98735  57.61014 0.05022219654545      2.102        3.69       0.000284
 2021-Oct-28 00:00 *     3.54852  62.32703 0.04635825822184      2.351        4.55       0.000259
 2021-Oct-29 00:00 *     9.46456  67.66212 0.04291567678252      2.616        5.56       0.000233
 2021-Oct-30 00:00 *    20.68555  73.38080 0.03999848810108      2.876        6.63       0.000210
 2021-Oct-31 00:00 *    45.42211  78.39019 0.03772408324704      3.093        7.63       0.000198
 2021-Nov-01 00:00 *    90.28508  79.20753 0.03620933343962      3.222        8.32       0.000209
 2021-Nov-02 00:00 *   123.43130  74.04007 0.03554729051500      3.222        8.49       0.000243
 2021-Nov-03 00:00 *   138.35888  66.35217 0.03578142092923      3.083        8.05       0.000293
 2021-Nov-04 00:00 *m  145.78778  58.24238 0.03689108918537      2.831        7.13       0.000346

JPL/Horizons solution 22, # obs: 76 (2017-2018)
2021 Aug 31, OCC = 5
 Date__(UT)__HR:MN     R.A._(a-appar)_DEC.            delta POS_3sigma  DOP_X_3sig  RT_delay_3sig
 2021-Oct-25 00:00 *   356.69473  50.46186 0.05866774638664  15071.629    19695.43       1.376467
 2021-Oct-27 00:00 *     1.03103  58.18721 0.05007502823548  18278.824    30473.49       0.898713
 2021-Oct-29 00:00 *    11.45380  68.26593 0.04288238724517  21876.222    45020.96       0.172672
 2021-Oct-31 00:00 *    50.79061  78.45808 0.03785117817784  24490.161    58869.97       0.844160
 2021-Nov-01 00:00 *    94.59995  78.50707 0.03643007316245  24640.723    61958.88       1.434469
 2021-Nov-02 00:00 *   124.61657  73.04662 0.03586362451173  23671.199    60541.87       2.034416
 2021-Nov-03 00:00 *   138.52194  65.39407 0.03618806808129  21628.264    54604.28       2.598868
 2021-Nov-04 00:00 *m  145.67163  57.40594 0.03737661300840  18854.974    45667.04       3.090190

Astrometry in the second or third week of September would be ideal before the plane-of-sky 
position uncertainties grow to large values.

Apparent Magnitudes, Solar Elongations, Lunar Elongations, and Lunar Illumination: 2017 TS3 Solution 22 (OCC = 5) 2021 Aug 31 Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta APmag S-brt S-O-T /r T-O-M/MN_Illu% 2021-Sep-23 00:00 352.32613 19.89952 0.25252071685327 20.485 n.a. 158.7381 /T 32.8/ 95.8587 2021-Sep-25 00:00 352.14268 20.56691 0.23800534906087 20.355 n.a. 158.0725 /T 50.9/ 85.0024 2021-Sep-27 00:00 351.95764 21.27405 0.22386520648912 20.224 n.a. 157.2336 /T 71.3/ 69.3338 2021-Sep-29 00:00 351.77513 22.02868 0.21008404712356 20.093 n.a. 156.2380 /T 92.1/ 50.9124 2021-Oct-01 00:00 351.60010 22.84049 0.19664559419955 19.960 n.a. 155.1032 /T 113.0/ 31.8368 2021-Oct-03 00:00 351.43867 23.72173 0.18353371952298 19.824 n.a. 153.8471 /T 133.1/ 14.7154 2021-Oct-05 00:00 351.29845 24.68815 0.17073263505801 19.684 n.a. 152.4862 /T 147.7/ 3.0327 2021-Oct-07 00:00 351.18914 25.76024 0.15822699656805 19.539 n.a. 151.0354 /T 144.9/ 0.4949 2021-Oct-09 00:00 351.12300 26.96507 0.14600210625869 19.387 n.a. 149.5071 /T 126.3/ 8.9290 2021-Oct-11 00:00 351.11544 28.33865 0.13404482109798 19.226 n.a. 147.9100 /T 103.4/ 26.4925 2021-Oct-13 00:00 351.18618 29.92935 0.12234569288464 19.054 n.a. 146.2474 /T 80.9/ 48.5234 2021-Oct-15 00:00 351.36187 31.80307 0.11090225116277 18.871 n.a. 144.5152 /T 61.0/ 69.9917 2021-Oct-17 00:00 351.68119 34.05145 0.09972330410899 18.673 n.a. 142.6970 /T 46.3/ 87.0398 2021-Oct-19 00:00 352.20495 36.80478 0.08883497257385 18.459 n.a. 140.7567 /T 40.7/ 97.2992 2021-Oct-21 00:00 353.03709 40.25227 0.07829028875842 18.228 n.a. 138.6235 /T 45.2/ 99.8139 2021-Oct-23 00:00 354.37439 44.67263 0.06818571852626 17.981 n.a. 136.1635 /T 55.4/ 94.8626 2021-Oct-25 00:00 356.64216 50.47262 0.05869056779753 17.725 n.a. 133.1291 /T 66.3/ 83.5882 2021-Oct-27 00:00 0.95619 58.19757 0.05009837246281 17.481 n.a. 129.0796 /T 74.8/ 67.5496 2021-Oct-29 00:00 11.32829 68.27870 0.04290505752431 17.293 n.a. 123.3281 /T 78.9/ 48.5180 2021-Oct-31 00:00 50.58334 78.49737 0.03787098094284 17.247 n.a. 115.1785 /L 78.3/ 28.7324 2021-Nov-02 00:00 124.68225 73.10795 0.03587763004631 17.437 n.a. 104.8754 /L 77.1/ 11.4821 2021-Nov-04 00:00 145.73425 57.46103 0.03738280582157 17.874 n.a. 94.4216 /L 83.3/ 1.2160

Setups


If the diameter is close to 0.12 km, then the 34.7 h rotation period implies a bandwidth
of about 0.35 Hz for an equatorial view.


CW setup:
---------------------------------------------------------------------------
TX polarization           RCP
RCV polarization          LCP & RCP
Frequency hops:           no hopping
Bandwidth:               5000 Hz 
TXoffset                 +500 Hz
FFT                     50000 for 0.1 Hz resolution 

Ranging setups below will need changes to deal with the narrow bandwidth.

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       490 Hz   
FFT             128
resolution        3.8 Hz
TXoffset        +50 Hz  (echo in column 77)
---------------------------------------------------------------------

Instructions

NOTE: Data should be moved to the appropriate subdirectories in aardvark:/export/data0/2017ts3/raw/

POINTING:

  OSOD and predicts are on aardvark:



POINTING  

...Not yet available...

Transmit offsets are given in millidegrees.  


PRDX.OUT.14f-14-14.s?? TRANSMITTER: STATION #14, RECEIVER: STATION #14 RECEIVER U.T. RANGE DOPPLER LHA DEC RA EL

2017 TS3 GOLDSTONE MASTERLOG

============================================================================== ----------------------------------------------------- ...Not yet available... -----------------------------------------------------
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/2017TS3/2017TS3.2021.goldstone.planning.html

Asteroid Radar Astronomy
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