Goldstone Radar Observations Planning: (418135) 2008 AG33


Background


(418135) 2008 AG33
2008 AG33 was discovered on January 12, 2008 by the Mt. Lemmon Survey. 

Nothing is known about 2008 AG33 other than its 
absolute magnitude of 19.5, which suggests a diameter of about 400 meters.

This asteroid will approach within 0.022 au on April 28 when the Goldstone SNRs
should be strong enough for delay-Doppler imaging.
Three tracks are scheduled at Goldstone from April 22-24 prior to the closest approach.

Time is also scheduled at DSS-43 and the Australian Telescope Compact Array on April 28.  

Bistatic test observations are scheduled at DSS-63 (Madrid) with reception at Effelsberg,
Germany on April 28.  

2008 AG33 will reach about 16th magnitude shortly after the flyby and be a reasonably 
good target for lightcurves for observers in the southern hemisphere.  The asteroid may also
move through the field of regard for NASA's NEOWISE spacecraft around May 6-7. 

2008 AG33 is classified as a "Potentially Hazardous Asteroid" by the Minor Planet Center.


Orbital and Physical Characteristics  
Name                     2008 AG33
Number                   418135                   
Discoverer               Mt. Lemmon Survey
Discovery date           2008 Jan 12
orbit type               Apollo                   

Close approach dist.     0.0217 au (8.4 lunar distances)
Close approach date      2022 Apr 28

semimajor axis           1.461 au                 
eccentricity             0.337                  
inclination              16.0 deg                  
Orbital period           1.77 y                   
Perihelion distance      0.968 au                 
aphelion distance        1.953 au                 
MOID                     0.0157 au                

absolute magnitude (H)   19.5                   
Diameter                ~0.4 km                  
Rotation period          Unknown                  
lightcurve amplitude     Unknown                  
spectral class           Unknown                  
                         PHA                      
                                                  
Last update: 2022 April 28


Goldstone Radar Echoes from Asteroid 2008 AG33



Echo power spectrum of 2008 AG33 obtained on April 23.  Echo power in standard deviations
is plotted versus Doppler frequency.  The echo has a deep central dip that suggests a
bifurcated shape.


Collages of images from April 22, 23, and 24.
In each panel, range increases down and Doppler frequency increases to the right. 
The resolution is 18.75 m x 0.03 Hz.  Each panel is a weighted sum of 20 runs.

The images reveal that 2008 AG33 is elongated, distinctly bifurcated, and that 
it rotates relatively slowly with a period of roughly 16-20 hours.
Echo power is visible in at least 18 rows and places a lower bound on the long
axis of about 330 meters.



Discovery M.P.E.C.


2008 AG33
https://www.minorplanetcenter.net/mpec/K08/K08B02.html


SNR Calculations


GOLDSTONE SNRs
2008 AG33
2008 AG33:  D = 0.4 km,  P = 2.2 h,  OC albedo = 0.1

wk DOY         start date    window       RA, dec   dist   runs  SNR/day SNR/run
15 105-106 2022 Apr 15-16  08:23-04:13     5, +73  0.077    466     27      1
15 106-107 2022 Apr 16-17  08:48-03:40     4, +71  0.071    478     36      2
15 107-108 2022 Apr 17-18  09:09-03:09     3, +70  0.066    496     49      2
16 108-109 2022 Apr 18-19  09:27-02:40     3, +68  0.060    518     69      3
16 109-110 2022 Apr 19-20  09:45-02:11     2, +66  0.055    545    100      5
16 110-111 2022 Apr 20-21  10:01-01:43     2, +63  0.049    577    150      7
16 111-112 2022 Apr 21-22  10:18-01:15     1, +60  0.044    616    230     10
16 112-113 2022 Apr 22-23  10:35-00:47     1, +55  0.039    662    370     16 Scheduled 1830-0045  Also WF Test
16 113-114 2022 Apr 23-24  10:53-00:18     0, +50  0.034    714    610     25 Scheduled 1930-0015  Also WF Test
16 114     2022 Apr 24     11:12-23:47     0, +43  0.030    768   1000     40 Scheduled 1930-2330  Also 1996 FG3
17 115     2022 Apr 25     11:35-23:13   359, +33  0.026    813   1700     64                      
17 116     2022 Apr 26     12:01-22:34   359, +20  0.023    824   2500     95                     
17 117     2022 Apr 27     12:35-21:48   359,  +6  0.022    767   3000    120                     
17 118     2022 Apr 28     13:21-20:50   358, -10  0.022    619   2500    110 Test at Madrid > Effelsberg 
17 119     2022 Apr 29     14:28-19:32   358, -24  0.024    389   1300     72                      

This object moves too far south to track at Goldstone after April 29.

We are expecting a bandwidth of less than 20 Hz.


Track Assignments


Goldstone tracks:
         UT         UT                     PDT                 Duration RTT    SNR/
DOY      Date       TX Window              TX Window           hh:mm    (sec)  run   Observer
112-113  Apr 22-23  1830-0045  2008 AG33   1130-1745 Apr 22     6:15     39    16     MB   Also WF Test
113-114  Apr 23-24  1930-0015  2008 AG33   1230-1715 Apr 23     4:45     34    25     MB   Also WF Test
114      Apr 24     1930-2330  2008 AG33   1230-1630 Apr 24     4:00     30    40     MB   Also 1996 FG3: right after AG33



Uncertainties


2008 AG33
From Jon Giorigini, 2022 April 20:
Based on 141 optical measurements spanning 2003-Sep-27 to
2022-April-17, orbit solution #38 was estimated and found to have
th following 3-sigma X-band uncertainties:

Date__(UT)__HR:MN  POS_3sigma    DOP_X_3sig  RT_delay_3sig
2022-Apr-22 00:00       2.910          4.37       0.000374
2022-Apr-22 12:00       3.127          4.50       0.000366
2022-Apr-23 00:00       3.366          5.62       0.000357
2022-Apr-23 12:00       3.629          5.92       0.000348
2022-Apr-24 00:00       3.916          7.33       0.000340
2022-Apr-24 12:00       4.224          7.88       0.000334
2022-Apr-25 00:00       4.541          9.56       0.000331

JPL/Horizons solution 35, # obs: 136 (2003-2022)
2022 Mar 28
 Date__(UT)__HR:MN     R.A._(a-appar)_DEC.             delta  POS_3sigma   DOP_X_3sig  RT_delay_3sig
 2022-Apr-20 00:00 *     2.00605  65.16581  0.05335331243098       7.767         9.91       0.000530
 2022-Apr-21 00:00 *     1.47374  62.30794  0.04792834768260       8.804        12.30       0.000445
 2022-Apr-22 00:00 *     0.96881  58.70770  0.04265472627442      10.056        15.51       0.000352
 2022-Apr-23 00:00 *     0.49221  54.09269  0.03760004209418      11.553        19.83       0.000279
 2022-Apr-24 00:00 *     0.04419  48.07680  0.03286850899554      13.276        25.56       0.000319
 2022-Apr-25 00:00 *   359.62428  40.14395  0.02862289434308      15.064        32.56       0.000520
 2022-Apr-26 00:00 *   359.23143  29.72197  0.02511170193297      16.425        39.33       0.000838
 2022-Apr-27 00:00 *   358.86403  16.51657  0.02267797205741      16.423        41.63       0.001225
 2022-Apr-28 00:00 *   358.52002   1.17893  0.02168521991634      14.298        34.55       0.001600
 2022-Apr-29 00:00 *m  358.19695 -14.39908  0.02232276470708      10.921        20.21       0.001865
 2022-Apr-30 00:00 *m  357.89207 -28.15998  0.02445876125518       8.407         7.80       0.001986
 2022-May-01 00:00 *m  357.60239 -39.18099  0.02774409457813       7.460         4.79       0.001998


Apparent Magnitudes, Solar Elongations, Lunar Elongations, and Lunar Illumination: 2008 AG33 Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta APmag S-brt S-O-T /r T-O-M/MN_Illu% 2022-Apr-11 00:00 7.64648 76.36797 0.10452715684247 18.474 n.a. 68.4443 /L 75.9/ 66.3709 2022-Apr-12 00:00 7.00561 75.76949 0.09879749492623 18.420 n.a. 67.5837 /L 82.1/ 75.3497 2022-Apr-13 00:00 6.36175 75.07732 0.09306063220931 18.364 n.a. 66.6559 /L 89.0/ 83.5399 2022-Apr-14 00:00 5.71862 74.27326 0.08732236082182 18.307 n.a. 65.6477 /L 96.3/ 90.5286 2022-Apr-15 00:00 5.08014 73.33427 0.08158947353150 18.249 n.a. 64.5425 /L 103.7/ 95.8681 2022-Apr-16 00:00 4.45034 72.23076 0.07587011621568 18.192 n.a. 63.3197 /L 110.7/ 99.1175 2022-Apr-17 00:00 3.83325 70.92414 0.07017430361481 18.136 n.a. 61.9524 /L 116.7/ 99.9093 2022-Apr-18 00:00 3.23273 69.36325 0.06451469506848 18.084 n.a. 60.4065 /L 120.9/ 98.0258 2022-Apr-19 00:00 2.65229 67.47900 0.05890779377831 18.040 n.a. 58.6371 /L 122.3/ 93.4625 2022-Apr-20 00:00 2.09498 65.17630 0.05337584844879 18. n.a. 56.5861 /L 120.5/ 86.4511 2022-Apr-21 00:00 1.56322 62.32194 0.04794993738514 18. n.a. 54.1789 /L 115.1/ 77.4333 2022-Apr-22 00:00 1.05872 58.72626 0.04267506541777 18. n.a. 51.3231 /L 106.6/ 66.9947 2022-Apr-23 00:00 0.58243 54.11727 0.03761868040816 18. n.a. 47.9200 /L 95.4/ 55.7854 2022-Apr-24 00:00 0.13461 48.10931 0.03288477077230 18. n.a. 43.9155 /L 81.7/ 44.4500 2022-Apr-25 00:00 359.71482 40.18653 0.02863577462096 19. n.a. 39.4771 /L 65.5/ 33.5802 2022-Apr-26 00:00 359.32199 29.77596 0.02511979848239 19. n.a. 35.4861 /L 46.5/ 23.6877 2022-Apr-27 00:00 358.95455 16.58006 0.02267966692460 19. n.a. 34.2770 /L 24.9/ 15.1915 2022-Apr-28 00:00 358.61043 1.24421 0.02167941015040 18. n.a. 38.5111 /L 7.553/ 8.4115 2022-Apr-29 00:00 358.28721 -14.34247 0.02230977634336 17. n.a. 47.3209 /L 26.0/ 3.5648 2022-Apr-30 00:00 357.98213 -28.11787 0.02444022512846 16. n.a. 57.2524 /L 47.8/ 0.7652 2022-May-01 00:00 357.69221 -39.15284 0.02772188250813 16.049 n.a. 66.0443 /L 66.8/ 0.0284 2022-May-02 00:00 357.41425 -47.60309 0.03179492231186 15.921 n.a. 73.1240 /L 82.7/ 1.2829 2022-May-03 00:00 357.14488 -54.02306 0.03638919700310 15.920 n.a. 78.6781 /L 96.0/ 4.3881 2022-May-04 00:00 356.88055 -58.95295 0.04132591095692 15.985 n.a. 83.0532 /L 106.8/ 9.1549 2022-May-05 00:00 356.61756 -62.80671 0.04649088012599 16.083 n.a. 86.5551 /L 115.3/ 15.3661 2022-May-06 00:00 356.35200 -65.87835 0.05181077926985 16.195 n.a. 89.4131 /L 121.5/ 22.7921 2022-May-07 00:00 356.07980 -68.37287 0.05723744813710 16.313 n.a. 91.7919 /L 125.1/ 31.1990 2022-May-08 00:00 355.79665 -70.43380 0.06273834620708 16.432 n.a. 93.8084 /L 126.3/ 40.3480 2022-May-09 00:00 355.49805 -72.16303 0.06829083627884 16.548 n.a. 95.5466 /L 124.9/ 49.9863 2022-May-10 00:00 355.17923 -73.63415 0.07387872438574 16.661 n.a. 97.0672 /L 121.4/ 59.8307 2022-May-11 00:00 354.83518 -74.90124 0.07949012100197 16.769 n.a. 98.4154 /L 116.1/ 69.5472 2022-May-12 00:00 354.46058 -76.00477 0.08511608647324 16.873 n.a. 99.6248 /L 109.4/ 78.7322 2022-May-13 00:00 354.04979 -76.97546 0.09074975263996 16.973 n.a. 100.7210 /L 101.9/ 86.9049 2022-May-14 00:00 353.59674 -77.83705 0.09638574212182 17.069 n.a. 101.7239 /L 93.8/ 93.5225 2022-May-15 00:00 353.09486 -78.60807 0.10201978016165 17.160 n.a. 102.6491 /L 85.5/ 98.0316 2022-May-16 00:00 352.53689 -79.30322 0.10764843543595 17.247 n.a. 103.5089 /L 77.5/ 99.9547 2022-May-17 00:00 351.91471 -79.93424 0.11326894889499 17.331 n.a. 104.3133 /L 70.2/ 98.9953 2022-May-18 00:00 351.21914 -80.51060 0.11887912126186 17.411 n.a. 105.0704 /L 64.4/ 95.1235 2022-May-19 00:00 350.43974 -81.03994 0.12447723606590 17.488 n.a. 105.7868 /L 60.6/ 88.6013 2022-May-20 00:00 349.56467 -81.52843 0.13006200046608 17.562 n.a. 106.4681 /L 59.2/ 79.9353

Setups




CW setup:
TX polarization     RCP
RCV polarization    LCP & RCP
Frequency hops:     no hopping
Bandwidth:          5000 Hz 
TXoffset            +500 Hz
FFT                 5000 for 1 Hz resolution 


Ranging setups:
---------------------------------------------------------------------------
10-usec
baud             10 usec
code            127
PRP            1270 usec
FFT              64
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             128 
ncoh              1
bandwidth      3921.6 Hz   
resolution       30.6  Hz
TXOFF          +500 Hz 
Time delay extent: 38250 meters
---------------------------------------------------------------------


Instructions

NOTE: Data should be moved to the appropriate subdirectories in aardvark:/export/data0/a418135/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

2008 AG33 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/2008AG33/2008AG33.2022.planning.html

Asteroid Radar Astronomy
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