2005 GC120 Goldstone Radar Observations Planning
2005 GC120 was discovered on April 12, 2005 by the Catalina Sky Survey in Arizona. This object has an absolute magnitude of 19.6, suggesting a diameter within a factor of two of 380 meters. 2005 GC120 has eccentric (e~0.5) and inclined (i~16.5 deg) orbit that crosses orbits of Venus, Earth, and Mars. 2005 GC120 will approach within 0.043 AU (~16.9 lunar distances) on Dec. 1, 2010, when it will be a moderate radar target. For optical observations, 2005 GC120 is too close to the Sun until Nov. 29, when it emerges as a 17.6 mag object at southern declinations. Goldstone radar observations are scheduled on Nov. 30 and Dec. 4. THE TRACK ON DECEMBER 4 HAS BEEN CANCELLED DUE TO PROBLEMS WITH THE AZIMUTH BEARING. 2005 GC120 has been classified as a "Potentially Hazardous Asteroid" by the Minor Planet Center.
Orbital and Physical Characteristics orbit type Apollo semimajor axis 1.193 AU eccentricity 0.497 inclination 16.5° perihelion distance 0.599 AU aphelion distance 1.787 AU absolute magnitude (H) 19.6 diameter 0.38 km (plus/minus a factor of two) rotation period unknown pole direction unknown lightcurve amplitude unknown spectral class unknown Last update: 2010 Dec 02
M.P.E.C. 2005-G87 Issued 2005 Apr. 13, 10:51 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.
Supported in part by the Brinson Foundation
Prepared using the Tamkin Foundation Computer Network
MPC@CFA.HARVARD.EDU
URL http://cfa-www.harvard.edu/iau/mpc.html ISSN 1523-6714
2005 GC120
Observations:
K05GC0C* C2005 04 12.31682 13 23 42.73 +39 59 02.6 20.0 R EG087703
K05GC0C C2005 04 12.32518 13 23 40.81 +39 59 15.0 19.7 R EG087703
K05GC0C C2005 04 12.33353 13 23 38.70 +39 59 25.7 19.2 R EG087703
K05GC0C C2005 04 12.34177 13 23 36.71 +39 59 37.6 20.2 R EG087703
K05GC0C C2005 04 12.89663 13 21 26.45 +40 12 22.5 19.4 R EG087176
K05GC0C C2005 04 12.92141 13 21 20.36 +40 12 55.8 19.8 R EG087176
K05GC0C C2005 04 12.92451 13 21 19.59 +40 13 00.0 19.5 R EG087176
K05GC0C C2005 04 12.92760 13 21 18.83 +40 13 04.2 19.3 R EG087176
K05GC0C C2005 04 13.13573 13 20 29.68 +40 17 44.8 19.0 R EG087G90
K05GC0C C2005 04 13.14049 13 20 28.51 +40 17 51.6 19.1 R EG087G90
K05GC0C C2005 04 13.14524 13 20 27.34 +40 17 58.4 18.8 R EG087G90
K05GC0C C2005 04 13.19461 13 20 15.20 +40 19 08.1 19.9 R EG087854
K05GC0C C2005 04 13.19844 13 20 14.03 +40 19 13.6 19.8 R EG087854
K05GC0C C2005 04 13.20227 13 20 13.20 +40 19 17.3 20.1 R EG087854
K05GC0C 5C2005 04 13.35451 13 19 35.31 +40 22 45.6 17.0 R EG087673
K05GC0C 5C2005 04 13.35799 13 19 34.40 +40 22 48.2 EG087673
K05GC0C 5C2005 04 13.36493 13 19 32.59 +40 22 57.6 EG087673
K05GC0C 5C2005 04 13.36875 13 19 31.61 +40 23 02.6 EG087673
K05GC0C 5C2005 04 13.37639 13 19 29.61 +40 23 13.1 EG087673
K05GC0C 5C2005 04 13.37917 13 19 29.02 +40 23 16.0 EG087673
Observer details:
176 Observatori Astronomic de Consell. Observers A. Lopez, R. Pacheco,
J. Forteza. 0.41-m f/4 reflector + CCD.
673 Table Mountain Observatory, Wrightwood. Observer D. Mayes. 0.6-m
reflector + CCD.
703 Catalina Sky Survey. Observer S. M. Larson. Measurers E. C. Beshore,
C. M. Casey, E. J. Christensen, G. J. Garradd, A. D. Grauer, R. E. Hill,
S. M. Larson, R. H. McNaught. 0.68-m Schmidt + CCD.
854 Sabino Canyon Observatory, Tucson. Observer J. E. McGaha. 0.36-m f/10.0
Schmidt-Cassegrain + CCD.
G90 Three Buttes Observatory, Tucson. Observer G. R. Jones. 0.40-m
Ritchey-Chretien + CCD.
Orbital elements:
2005 GC120 PHA 0.014A
Epoch 2005 Mar. 31.0 TT = JDT 2453460.5 MPC
M 277.54159 (2000.0) P Q
n 0.74516410 Peri. 258.61648 +0.79537429 +0.54243231
a 1.2049474 Node 67.98964 -0.37655644 +0.79186703
e 0.5144070 Incl. 16.96087 -0.47495787 +0.28055980
P 1.32 H 19.5 G 0.15
From 20 observations 2005 Apr. 12-13.
Ephemeris:
2005 GC120 a,e,i = 1.20, 0.51, 17 q = 0.5851
Date TT R. A. (2000) Decl. Delta r Elong. Phase V
2005 04 10 13 32.40 +39 02.5 0.453 1.351 132.9 32.9 19.8
2005 04 20 12 50.05 +42 24.5 0.406 1.279 124.3 40.5 19.7
2005 04 30 11 58.33 +43 21.7 0.373 1.200 112.5 50.9 19.6
2005 05 10 11 05.03 +41 26.5 0.349 1.117 98.6 63.4 19.7
2005 05 20 10 15.65 +37 01.5 0.330 1.028 83.5 77.9 19.9
2005 05 30 09 28.71 +30 45.3 0.314 0.936 66.9 95.1 20.2
Timothy B. Spahr (C) Copyright 2005 MPC M.P.E.C. 2005-G87
Target Name: 2005 GC120
HMag: 19.6
Diameter: 0.38 km (plus/minus a factor of two)
Period: 2.1 h
# max
Start date UT window RA, dec dist runs SNR SNR/run
----------------------------------------------------------------
2010 Nov 30 00:03-02:11 327, -33 0.045 67 46 6
2010 Nov 30 23:01-04:37 338, -23 0.043 187 100 8
2010 Dec 01 22:41-06:08 348, -12 0.044 246 120 9
2010 Dec 02 22:32-07:12 357, -2 0.048 269 100 7
2010 Dec 03 22:29-07:59 3, 7 0.054 268 72 5
2010 Dec 04 22:29-08:33 9, 13 0.061 256 45 3 CANCELLED
Goldstone SNRs assume Ptx = 430 kW
Goldstone tracks:
UT UT PDT Duration Round-trip
DOY Date TX Window TX Window hh:mm time (sec) SNR/Run
--- ---- --------- --------- --------- ------- -------
335 Dec 01 0030 0435 1630 2035 Nov 30 4:05 43 8
338 Dec 04 0520 0755 2120 2355 Dec 03 2:35 55 3 CANCELLED
From Jon Giorgini, Nov 27 2010: Solution #16 was calculated based on 84 optical measurements (2005-Apr-4 to 2010-Mar-6). Formal 3-sigma X-band uncertainties: Date__(UT)__HR:MN POS_3sigma DOP_X_3sig RT_delay_3sig 2010-Dec-01 00:00 19.957 4.13 0.008227 2010-Dec-02 00:00 24.129 4.64 0.007626 2010-Dec-03 00:00 26.796 6.04 0.006805 2010-Dec-04 00:00 27.043 7.33 0.005983 2010-Dec-05 00:00 25.665 8.24 0.005292 From JPL Horizons, Mar 07 2010, Solution #14, #obs 84 (2005-2010 data arc) Date__(UT)__HR:MN POS_3sigma DOP_S_3sig DOP_X_3sig RT_delay_3sig 2010-Nov-30 00:00 16.938 1.46 5.21 0.008301 2010-Dec-01 00:00 19.843 1.14 4.09 0.008051 2010-Dec-02 00:00 23.981 1.27 4.53 0.007443 2010-Dec-03 00:00 26.555 1.64 5.88 0.006627 2010-Dec-04 00:00 26.730 2.00 7.15 0.005815 2010-Dec-05 00:00 25.317 2.25 8.05 0.005137 2010-Dec-06 00:00 23.257 2.41 8.63 0.004623 2010-Dec-07 00:00 21.104 2.51 8.99 0.004249 2010-Dec-08 00:00 19.100 2.57 9.19 0.003984 Apparent Magnitudes and Solar Elongations: Date__(UT)__HR:MN R.A._(J2000.0)_DEC. APmag delta S-O-T /r 2010-Nov-27 00:00 291.29573 -48.87714 n.a. 0.06353083188875 47.5658 /T 2010-Nov-28 00:00 301.93360 -45.97419 n.a. 0.05600752097128 53.1301 /T 2010-Nov-29 00:00 313.73785 -41.01038 17.64 0.04980536585133 60.6616 /T 2010-Nov-30 00:00 325.83552 -33.50368 16.86 0.04545492838132 70.3778 /T 2010-Dec-01 00:00 337.22301 -23.71296 16.20 0.04350586743277 81.8183 /T 2010-Dec-02 00:00 347.20499 -12.91849 15.77 0.04427160183250 93.6438 /T 2010-Dec-03 00:00 355.55629 -2.76157 15.57 0.04762060006589 104.2821 /T 2010-Dec-04 00:00 2.38531 5.74727 15.55 0.05306851073423 112.8508 /T 2010-Dec-05 00:00 7.93707 12.43328 15.64 0.06005158833858 119.3043 /T 2010-Dec-06 00:00 12.47001 17.56313 15.79 0.06810563771218 124.0122 /T 2010-Dec-07 00:00 16.20671 21.49720 15.97 0.07690233620025 127.4081 /T 2010-Dec-08 00:00 19.32383 24.54677 16.16 0.08622277306494 129.8519 /T 2010-Dec-09 00:00 21.95696 26.94652 16.35 0.09592288948710 131.6090 /T 2010-Dec-10 00:00 24.20904 28.86527 16.54 0.10590712248794 132.8669 /T 2010-Dec-11 00:00 26.15823 30.42308 16.73 0.11611101946040 133.7571 /T 2010-Dec-12 00:00 27.86424 31.70574 16.91 0.12649027261053 134.3716 /T 2010-Dec-13 00:00 29.37307 32.77524 17.08 0.13701384557826 134.7761 /T 2010-Dec-14 00:00 30.72056 33.67706 17.24 0.14765962096611 135.0177 /T 2010-Dec-15 00:00 31.93486 34.44505 17.40 0.15841159706084 135.1312 /T
CW setup:
---------------------------------------------------------------------------
TX polarization RCP
RCV polarization LCP & RCP
Frequency hops: 2
Dwell 20 seconds
Bandwidth: 4000 Hz
Sampling interval: 2500 x 0.1 usec
VME FFT for PSD files: 4096 for 0.98-Hz resolution
Ranging setups:
---------------------------------------------------------------------------
127 x 64 10-usec single sample
baud 10 usec
code 127
gates 127
PRP 1270 usec
FFT 64
CLT VME ?
PFS ?
ncoh 4
bandwidth 196.9 Hz
resolution 3.1 Hz
TXOFF +50 Hz -> echo will be centered at +16 bins or in bin 32 + 16 = 48
---------------------------------------------------------------------------
127 x 64 11-usec single sample
baud 11 usec
code 127
gates 127
PRP 1397 usec
FFT 64
CLT VME ?
PFS ?
ncoh 4
bandwidth 179.0 Hz
resolution 2.8 Hz
TXOFF +50 Hz --> echo will be centered at +18 bins or in bin 32 + 18 = 50
-------------------------------------------------------------------------
1-usec single sample
baud 1 usec
code 127
ncoh 20
bandwidth 393.7 Hz
FFT 128
dfreq 3.1 Hz
TXoff +50 Hz (echo in bin 64+16 =80)
-------------------------------------------------------------------------------
0.25-usec imaging
baud 0.25 usec
code 127
FFT 128
ncoh 246
bandwidth 128 Hz
resolution 1.00 Hz
TXOFF +20 Hz, echo is in bin 64+20=84
--------------------------------------------------------------------------
0.125-usec
------------
baud 0.125 usec
code 255
FFT 256
ncoh 122
bandwidth 257.15 Hz
resolution 1.0045 Hz
TXOFF +30 Hz to put echo at 128 + 30 = bin 158
_____________________________________________________________________
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
JX1XS070 7.000 1050 889.0 1124.9 17.6 3 375 5.9
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
____________________________________________________________________
OSOD and predicts are on aardvark:
/export/data3/osod/ops/2005gc120/PRDX.s16
/PUNCH.OUT.s16
/EPH.OUT.s16
POINTING
TX Offsets
Date (UTC) DOY hhmmss RA Dec Macro LHA Dec RTT OSOD
2010 12 01 335 000000 337.3981 -23.7036 A 43.4
2010 12 01 335 010000 337.8326 -23.2631 A 43.4
2010 12 01 335 020000 338.2641 -22.8197 A -5.2 5.4 43.4 s16
2010 12 01 335 030000 338.6934 -22.3736 A 43.3
2010 12 01 335 030000 338.6934 -22.3736 B 43.3
2010 12 01 335 040000 339.1212 -21.9251 B -5.1 5.4 43.3 s16
2010 12 01 335 050000 339.5483 -21.4745 B 43.3
Transmit offsets are given in millidegrees.
PRDX.OUT.s16
TRANSMITTER: STATION #14, RECEIVER: STATION #14
RECEIVER U.T. RANGE DOPPLER LHA DEC RA EL
2010 DEC 01 00:00 43.3951371368 68967.564 335.4597 -23.7034 337.398 26.468
2010 DEC 01 00:10 43.3903952097 66332.748 337.8939 -23.6302 337.471 27.343
2010 DEC 01 00:20 43.3858385064 63682.897 340.3282 -23.5569 337.543 28.145
2010 DEC 01 00:30 43.3814680248 61019.383 342.7625 -23.4836 337.616 28.870
2010 DEC 01 00:40 43.3772846737 58343.603 345.1970 -23.4101 337.688 29.516
2010 DEC 01 00:50 43.3732892629 55656.978 347.6316 -23.3366 337.761 30.081
2010 DEC 01 01:00 43.3694825103 52960.951 350.0662 -23.2629 337.833 30.561
2010 DEC 01 01:10 43.3658650156 50256.981 352.5010 -23.1892 337.905 30.956
2010 DEC 01 01:20 43.3624372920 47546.545 354.9358 -23.1155 337.977 31.262
2010 DEC 01 01:30 43.3591997324 44831.133 357.3707 -23.0416 338.049 31.479
2010 DEC 01 01:40 43.3561526332 42112.242 359.8056 -22.9677 338.121 31.606
2010 DEC 01 01:50 43.3532961934 39391.381 2.2407 -22.8937 338.193 31.642
2010 DEC 01 02:00 43.3506304901 36670.061 4.6758 -22.8196 338.264 31.586
2010 DEC 01 02:10 43.3481555025 33949.796 7.1109 -22.7454 338.336 31.440
2010 DEC 01 02:20 43.3458711115 31232.100 9.5462 -22.6712 338.408 31.203
2010 DEC 01 02:30 43.3437770762 28518.482 11.9814 -22.5969 338.479 30.877
2010 DEC 01 02:40 43.3418730659 25810.448 14.4168 -22.5225 338.551 30.463
2010 DEC 01 02:50 43.3401586208 23109.493 16.8521 -22.4480 338.622 29.963
2010 DEC 01 03:00 43.3386332168 20417.100 19.2875 -22.3735 338.694 29.379
2010 DEC 01 03:10 43.3372961782 17734.738 21.7230 -22.2989 338.765 28.714
2010 DEC 01 03:20 43.3361467669 15063.862 24.1585 -22.2243 338.836 27.971
2010 DEC 01 03:30 43.3351841196 12405.903 26.5940 -22.1496 338.908 27.151
2010 DEC 01 03:40 43.3344072893 9762.272 29.0296 -22.0748 338.979 26.258
2010 DEC 01 03:50 43.3338152152 7134.356 31.4652 -21.9999 339.050 25.296
2010 DEC 01 04:00 43.3334067481 4523.513 33.9008 -21.9250 339.121 24.267
2010 DEC 01 04:10 43.3331806445 1931.073 36.3364 -21.8501 339.193 23.174
2010 DEC 01 04:20 43.3331355731 -641.668 38.7721 -21.7750 339.264 22.021
2010 DEC 01 04:30 43.3332701049 -3193.448 41.2078 -21.7000 339.335 20.810
2010 DEC 01 04:40 43.3335827315 -5723.042 43.6434 -21.6248 339.406 19.546
2010 DEC 01 04:50 43.3340718603 -8229.263 46.0791 -21.5496 339.477 18.229
2010 DEC 01 05:00 43.3347357968 -10710.969 48.5148 -21.4744 339.548 16.865
2005GC120 GOLDSTONE MASTERLOG
==============================================================================
Receive TX
Setup hops dwell code ncoh FFT runs start -stop OSOD offset Poln Notes
------------------------------------------------------------------------------
POINTING
TX Offsets
Date (UTC) DOY hhmmss RA Dec Macro LHA Dec RTT OSOD
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/2005GC120/2005GC120_planning.html
Asteroid Radar Astronomy