2011 AH5 Goldstone Radar Observations Planning


Background



CANCELLED DUE TO EQUIPMENT PROBLEMS 

2011 AH5 was discovered on January 8, 2011 by the Catalina Sky Survey in Arizona. 
This object has an absolute magnitude of 25.9, suggesting a diameter within a 
factor of two of 21 meters.  As such, this is one of the smallest asteroids
we have attempted to observe at Goldstone.  Otherwise, nothing is known about 
its physical properties. 

2011 AH5 will approach within 0.0086 AU (3.4 lunar distances) on January 13,
when we have one short track scheduled from 10:20-12:20 UT.

We intend to _both_ bistatic and monostatic observations.  We're going to 
start with bistatic observations due to the very short 8.6 second round-trip time,
but if the SNRs are weak, we'll switch to monostatic observations.


Orbital and Physical Characteristics  
 orbit type               Apollo
 semimajor axis           1.080 AU     
 eccentricity             0.291
 inclination              6.9 deg
 perihelion distance      0.765 AU     
 aphelion distance        1.395 AU     
 absolute magnitude (H)   25.9
 diameter                ~21 meters 
 rotation period          unknown
 pole direction           unknown  
 lightcurve amplitude     unknown
 spectral class           unknown 

Last update: 2011 Jan 12

Discovery

 
M.P.E.C. 2011-A32                                Issued 2011 Jan.  9, 04:42 UT

     The Minor Planet Electronic Circulars contain information on unusual
         minor planets and routine data on comets.  They are published
   on behalf of Commission 20 of the International Astronomical Union by the
          Minor Planet Center, Smithsonian Astrophysical Observatory,
                          Cambridge, MA 02138, U.S.A.

             Prepared using the Tamkin Foundation Computer Network

                              MPC@CFA.HARVARD.EDU
       URL http://www.minorplanetcenter.org/iau/mpc.html  ISSN 1523-6714

                                   2011 AH5

Observations:
     K11A05H* C2011 01 08.33953 09 40 53.22 +43 42 10.5          19.5 VrEA032703
     K11A05H  C2011 01 08.34480 09 40 58.08 +43 42 09.7          19.9 VrEA032703
     K11A05H  C2011 01 08.34995 09 41 03.04 +43 42 07.7          19.7 VrEA032703
     K11A05H  C2011 01 08.35519 09 41 07.83 +43 42 06.4          19.9 VrEA032703
     K11A05H  C2011 01 08.39475 09 41 45.09 +43 41 49.9          19.7 VrEA032703
     K11A05H  C2011 01 08.40075 09 41 50.78 +43 41 46.7          19.9 VrEA032703
     K11A05H  C2011 01 08.41331 09 42 02.59 +43 41 39.7          19.2 VrEA032703
     K11A05H KC2011 01 08.45171 09 42 34.49 +43 40 17.6          19.6 RuEA032H36
     K11A05H KC2011 01 08.46076 09 42 43.50 +43 40 05.3          19.6 RuEA032H36
     K11A05H KC2011 01 08.47424 09 42 56.91 +43 39 47.7          19.5 RuEA032H36
     K11A05H KC2011 01 09.02361 09 54 42.05 +43 28 39.0                uEA032J95
     K11A05H KC2011 01 09.02830 09 54 48.05 +43 28 34.4                uEA032J95
     K11A05H KC2011 01 09.03230 09 54 53.15 +43 28 30.1          18.9 RuEA032J95

Observer details:
703 Catalina Sky Survey.  Observer S. M. Larson.  Measurers J. D. Ahern,
    E. C. Beshore, A. Boattini, G. J. Garradd, A. R. Gibbs, A. D. Grauer,
    R. E. Hill, R. A. Kowalski, S. M. Larson, R. H. McNaught.  0.68-m Schmidt
    + CCD.
H36 Sandlot Observatory, Scranton.  Observer G. Hug.  0.56-m reflector + CCD.
J95 Great Shefford.  Observer P. Birtwhistle.  0.40-m f/6.0 Schmidt-Cassegrain
    + CCD.

Orbital elements:
2011 AH5                                                 Earth MOID = 0.0039 AU
Epoch 2011 Feb. 8.0 TT = JDT 2455600.5                  MPC
M 326.40037              (2000.0)            P               Q
n   0.87942846     Peri.  266.79417     -0.92332781     +0.36884647
a   1.0789526      Node   294.82856     -0.28865059     -0.85015024
e   0.2882887      Incl.    6.76157     -0.25327178     -0.37576169
P   1.12           H   26.0           G   0.15           U   7
Residuals in seconds of arc
110108 703  0.5+  0.5+    110108 703  0.3+  0.3-    110109 J95  0.1-  0.1-
110108 703  0.5-  0.7+    110108 703  0.6-  0.9+    110109 J95  0.1+  0.1+
110108 703  0.9+  0.3-    110108 H36  0.2+  0.2+    110109 J95  0.2+  0.0
110108 703  0.6-  0.3-    110108 H36  0.6+  0.6-
110108 703  0.0   0.6-    110108 H36  0.4-  0.1-

Ephemeris:
2011 AH5                 a,e,i = 1.08, 0.29, 7                   q = 0.7679
Date    TT    R. A. (2000) Decl.     Delta      r     Elong.  Phase     V
2011 01 09    09 53.97   +43 30.4    0.0260   1.004   141.6    37.5    19.6
2011 01 10    10 21.92   +42 47.0    0.0208   0.999   137.6    41.6    19.2
2011 01 11    11 05.56   +40 42.8    0.0159   0.994   130.7    48.6    18.8
2011 01 12    12 15.61   +34 41.3    0.0117   0.989   117.4    62.0    18.5
2011 01 13    13 57.08   +18 45.6    0.00895  0.984    92.2    87.3    18.8
2011 01 14    15 42.73   -05 28.7    0.00928  0.979    59.6   119.9    20.6
2011 01 15    16 59.29   -22 00.4    0.0124   0.974    38.4   141.2    23.4

Carl W. Hergenrother         (C) Copyright 2011 MPC           M.P.E.C. 2011-A32

SNR Calculation

Target Name:    2011 AH5
HMag:           25.9
Diameter:      ~21 meters 
Period:         0.5 hours (a standard guess for very small NEAs)

               UTC                  Distance   #     SNR/   SNR/
 start date    window       RA  Dec   (AU)    runs   date   run
2011 Jan 11  05:38-18:22   175   38  0.014    700    100      4
2011 Jan 12  07:25-19:21   198   27  0.010    700    322     13
2011 Jan 13  10:27-19:59   228    2  0.009    700    477     19
2011 Jan 14  13:34-20:01   251  -19  0.011    543    140      7
2011 Jan 15  15:46-19:43   265  -29  0.016    279     27      2

Goldstone SNRs assume Ptx = 470 kW and monostatic observations.  Bistatic observations 
will produce SNRs only about 1/4 as strong.

Track Assignments


Goldstone tracks:

      UT        UT          PST                Duration  Round-trip
DOY   Date      TX Window   TX Window          hh:mm     time (sec)  SNR/Run 
---   ----      ---------   ---------          --------- -------     -------
013   Jan 13    1020-1220   0220-0420  Jan 13   2:00      8.6         19 


Uncertainties

From Jon Giorgini, 2011 Jan 12:

Now with 54 measurements (2011-Jan-8 to 2011-Jan-12 13:00),
2011 AH5 solution #10 was computed.

Formal 3-sigma X-band uncertainties:

 Date__(UT)__HR:MN   POS_3sigma   DOP_X_3sig  RT_delay_3sig
 2011-Jan-13 10:00        7.845        81.07       0.027990
 2011-Jan-13 11:00        8.014       129.19       0.028027
 2011-Jan-13 12:00        8.117       176.92       0.028084
 2011-Jan-13 13:00        8.180       224.14       0.028161
 2011-Jan-13 14:00        8.228       270.81       0.028258
 2011-Jan-13 15:00        8.285       316.87       0.028375
 2011-Jan-13 16:00        8.368       362.30       0.028511
 2011-Jan-13 17:00        8.484       407.07       0.028666
 2011-Jan-13 18:00        8.631       451.16       0.028840
 2011-Jan-13 19:00        8.798       494.55       0.029033
 2011-Jan-13 20:00        8.975       537.22       0.029244

Pointing knowledge can now support the track.

Change between prior s7 and current s10:

     RECEIVER    U.T.         RANGE         DOPPLER     LHA      DEC      RA      EL   
s10:2011 JAN 13 10:00      8.5686726148     1222.832 283.4272   7.5135 222.225  15.271
s07:2011 JAN 13 10:00      8.5848699229     1227.483 283.4320   7.5177 222.220  15.278
                           ------------     --------            ------ -------
 Delta:                   -0.0161973 sec      -4.651 Hz        -0.0042   0.005 deg
                           (0.95-sigma)     (0.09-sigma)       (1.3-sigma) 

So the change due to new measurements was very consistent
with the expected statistical uncertainties of s7.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 

From Jon Giorgini, 2011 Jan 11:

Including the H01/G96 optical data forwarded by e-mail,
27 measurements (2011-Jan-8 to 2011-Jan-11) result in 2011 AH5 
solution #7, with formal X-band uncertainties over the DSS-14
window given below:

 Date__(UT)__HR:MN   POS_3sigma   DOP_X_3sig  RT_delay_3sig   Azi_(a-appr)_Elev
 2011-Jan-13 10:00       55.649       161.97       0.050988    91.5967  15.2777
 2011-Jan-13 11:00       57.000       247.13       0.051029   101.0938  25.9233
 2011-Jan-13 12:00       58.189       331.88       0.051106   112.1383  36.1409
 2011-Jan-13 13:00       59.232       415.85       0.051218   126.0402  45.3423
 2011-Jan-13 14:00       60.150       498.87       0.051365   144.4143  52.5248
 2011-Jan-13 15:00       60.965       580.84       0.051547   167.7654  56.1838
 2011-Jan-13 16:00       61.699       661.69       0.051763   192.6893  55.0715
 2011-Jan-13 17:00       62.370       741.37       0.052013   213.9224  49.5196
 2011-Jan-13 18:00       62.994       819.85       0.052296   229.8901  40.9955
 2011-Jan-13 19:00       63.585       897.07       0.052612   241.8546  30.7767
 2011-Jan-13 20:00       64.154       973.01       0.052960   251.3304  19.6254

Adding astrometry spanning the 9-11th made about a 10" 
pointing correction. Fairly small relative to 3-sigma 
statistical uncertainties of 500" (i.e. pointing was 
well within formal statistics).

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 

Apparent Magnitudes and Solar Elongations:

 Date__(UT)__HR:MN     R.A._(J2000.0)_DEC.            delta  APmag    S-O-T /r
 2011-Jan-10 00:00     155.51018  42.77873 0.02079866437838  19.17 137.6064 /L
 2011-Jan-11 00:00     166.52219  40.68067 0.01585305354366  18.76 130.5792 /L
 2011-Jan-12 00:00     184.32397  34.49917 0.01154582212627  18.46 117.0486 /L
 2011-Jan-13 00:00     210.17038  18.03196 0.00885541673459  18.76  91.1362 /L
 2011-Jan-14 00:00     236.81702  -6.54609 0.00930880928030   n.a.  58.1804 /L
 2011-Jan-15 00:00     255.84503 -22.76136 0.01257346874632   n.a.  37.3509 /L
 2011-Jan-16 00:00     267.65614 -30.43000 0.01711461755440   n.a.  28.1891 /L
 2011-Jan-17 00:00     275.11625 -34.24099 0.02216813173156   n.a.  24.4676 /L

Setups


CW setup:

We don't know the rotation period, but most objects this small studied to date
have been very rapid rotators, so we have assumed a rotation period of only 
30 minutes.  Consequently, the bandwidth could be in the realm of several Hz.

The setup below assumes that the observations will be bistatic, with reception
at DSS-13 (i.e., 30 second integrations).  If we observe monostatically, 
we'll change the dwell to 10 seconds.

Closest approach occurs shortly before the transmit window opens.  At closest approach
the Doppler shift goes to zero, and as a result, DSS-14 transmissions could
interfere with reception of echoes at DSS-13 (via a ground wave), so be on the
alert for RFI during the early portion of the track.  We've seen this before but
not for a number of years.

---------------------------------------------------------------------------
TX polarization           RCP
RCV polarization          LCP & RCP
Frequency hops:           2                          
Dwell                     30 seconds                      
Bandwidth:                8000 Hz 
Sampling interval:        1250 x 0.1 usec
VME FFT for PSD files:    8192 for 0.98-Hz resolution 

Ranging setups:
---------------------------------------------------------------------------
10 usec ranging

baud             10 usec
code            127
FFT             128   
ncoh              1
bandwidth       787.4 Hz   
resolution        6.15 Hz
TXOFF          +100 Hz -> echo will be centered at +16 bins or in bin 64 + 16 = 80
---------------------------------------------------------------------------
11 usec ranging

baud             11 usec
code            127
FFT             128  
ncoh              1
bandwidth       715.8  Hz   
resolution        5.6  Hz
TXOFF          +100 Hz --> echo will be centered at +18 bins or in bin 64 + 18 = 82
-------------------------------------------------------------------------
1 usec ranging

baud              1 usec
code              255
FFT               128
ncoh              6
bandwidth         653.6  Hz
dfreq             5.1  Hz
TXoff            +100 Hz  (echo in bin 64+20 =84)
---------------------------------------------
Tentatively:

0.25-usec imaging  

baud            0.25 usec
code            255
FFT             128
ncoh             26
bandwidth       603.3 Hz    
resolution      4.7 Hz
TXOFF          +80  Hz, echo is in bin 64+17=81 

---------------------------------
0.125-usec imaging 

baud           0.125 usec
code           255  
FFT            128 
ncoh            56
bandwidth      560.2 Hz      
resolution     4.4 Hz
TXOFF          +80 Hz to put echo at  64 + 18 = bin 82 
_____________________________________________________________________
POSSIBLE RANGING SETUPS: (code=127, FFT=64, single-pol'n) 
   These are from JX, w/ max-band (min-acc) options from Ray Jurgens.
   Currently configured for 5-sec records.
_______________________________________________________________________
 Setup        Baud        RP         1-acc 1-acc      
            usec   m      usec        band   res    acc  band     res 
_______________________________________________________________________
 
JX1XS110  11.000 1650    1397.0      715.8  11.2      2   358     5.6
                                                      
JX1XS020   2.000  300     254.0     3937.0  61.5     12   328     5.1
                                                      4   984    15.4 

JX1XS010   1.000  150     127.0     7874.0 123.0     41   192     3.0 
                                                      8   984    15.4 

JX1XS005   0.500   75      63.5    15748.0 246.1    123   128     2.0 
                                                     15  1050    16.4 

JX1XS002   0.250   37.5    31.75   31496.1 492.1    492    64     1.0
                                                     30  1050    16.4 
 
JX1XS001   0.125   18.75   15.875  62992.1 984.3   1970    32     0.5 
                                                     60  1050    16.4 
____________________________________________________________________


Instructions

NOTE: Data should be moved to the appropriate subdirectories in aardvark:/export/data0/2011AH5/raw/

2010 JL33 POINTING:

  OSOD and predicts are on aardvark:

/export/data3/osod/ops/2011ah5/PRDX.s10
                              /PUNCH.OUT.s10
                              /EPH.OUT.s10

POINTING  
                                                      TX Offsets    
Date (UTC) DOY hhmmss RA       Dec         Macro     LHA     Dec    RTT    OSOD
2011 01 13 013 100000 222.2243  7.5138      A                       8.6     10 
2011 01 13 013 110000 223.3455  6.4490      A                       8.6
2011 01 13 013 120000 224.4461  5.3825      A       -2.6    -2.6    8.6
2011 01 13 013 130000 225.5274  4.3165      A                       8.6
2011 01 13 013 140000 226.5912  3.2534      A                       8.6

Transmit offsets are given in millidegrees.  


PRDX.OUT.s10 Bistatic PRDX (DSS14-DSS13): TRANSMITTER: STATION #14, RECEIVER: STATION #13 RECEIVER U.T. RANGE DOPPLER LHA DEC RA EL 2011 JAN 13 10:20 8.5688476097 -4182.779 288.1595 7.1596 222.601 18.933 2011 JAN 13 10:30 8.5692373120 -6941.616 290.4793 6.9822 222.788 20.718 2011 JAN 13 10:40 8.5698214481 -9730.424 292.7996 6.8047 222.975 22.496 2011 JAN 13 10:50 8.5706020915 -12548.628 295.1204 6.6271 223.161 24.266 2011 JAN 13 11:00 8.5715812886 -15395.600 297.4419 6.4494 223.346 26.028 2011 JAN 13 11:10 8.5727610249 -18270.657 299.7639 6.2717 223.531 27.777 2011 JAN 13 11:20 8.5741432513 -21173.066 302.0865 6.0940 223.715 29.513 2011 JAN 13 11:30 8.5757298503 -24102.040 304.4097 5.9163 223.899 31.234 2011 JAN 13 11:40 8.5775226551 -27056.743 306.7334 5.7385 224.082 32.936 2011 JAN 13 11:50 8.5795234458 -30036.291 309.0577 5.5607 224.264 34.617 2011 JAN 13 12:00 8.5817339300 -33039.749 311.3825 5.3829 224.447 36.274 2011 JAN 13 12:10 8.5841557289 -36066.138 313.7078 5.2052 224.628 37.903 2011 JAN 13 12:20 8.5867904291 -39114.431 316.0337 5.0275 224.809 39.502 Monostatic PRDX: TRANSMITTER: STATION #14, RECEIVER: STATION #14 RECEIVER U.T. RANGE DOPPLER LHA DEC RA EL 2011 JAN 13 10:20 8.5688799391 -4201.160 288.0648 7.1589 222.601 18.841 2011 JAN 13 10:30 8.5692708981 -6959.084 290.3845 6.9814 222.788 20.621 2011 JAN 13 10:40 8.5698562258 -9746.951 292.7048 6.8039 222.974 22.394 2011 JAN 13 10:50 8.5706379942 -12564.189 295.0257 6.6263 223.160 24.160 2011 JAN 13 11:00 8.5716182476 -15410.171 297.3471 6.4487 223.346 25.917 2011 JAN 13 11:10 8.5727989700 -18284.217 299.6691 6.2710 223.531 27.662 2011 JAN 13 11:20 8.5741821110 -21185.593 301.9917 6.0932 223.715 29.393 2011 JAN 13 11:30 8.5757695514 -24113.517 304.3148 5.9155 223.899 31.109 2011 JAN 13 11:40 8.5775631233 -27067.153 306.6385 5.7377 224.082 32.806 2011 JAN 13 11:50 8.5795646059 -30045.618 308.9627 5.5599 224.264 34.482 2011 JAN 13 12:00 8.5817757056 -33047.980 311.2875 5.3822 224.446 36.134 2011 JAN 13 12:10 8.5841980427 -36073.262 313.6129 5.2044 224.628 37.759 2011 JAN 13 12:20 8.5868332031 -39120.438 315.9387 5.0267 224.809 39.353

2011 AH5 GOLDSTONE MASTERLOG


Dr. Lance A. M. Benner | PHONE: (818) 354-7412 Mail Stop 300-233 | FAX: (818) 354-9476 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/2011AH5/2011AH5_planning.html

Asteroid Radar Astronomy
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