1998 RO1 Planning
Background
1998 RO1 was discovered by LINEAR on September 14, 1998. Arecibo radar observations in 2003
and 2004 showed that it is a binary system whose components have diameters of about 0.8 and 0.4 km.
Combined radar and photometric observations (by Petr Pravec et al.) showed that the rotation periods
are 2.5 and 14.55 h.
Our primary objective is to obtain a range. If ranging is successful in 2005 and again in 2006,
then it might be possible to detect the Yarkovsky acceleration for this object, and thus (because
the mass and bulk density are available from the secondary's orbit due to earlier radar observations)
constrain the thermal inertia. 1998 RO1 is the first near-Earth asteroid for which this might be
possible.
We have one track to observe this object: September 25. 1998 RO1 will be a weak radar target, so
unless the echoes are stronger than we expect, we will devote the entire track to ranging. We will
start with 10 usec, and if we get a relatively quick detection, then we'll go to 1 usec for the
rest of the track.
Orbital and Physical Characteristics
orbit type Aten
semimajor axis 0.991 AU
eccentricity 0.720
inclination 22.7°
perihelion distance 0.277 AU
aphelion distance 1.704 AU
absolute magnitude (H) 18.0
diameter 0.8 km (primary)
0.4 km (secondary)
rotation period 2.492 h (primary)
14.55 (secondary)
pole direction unknown
lightcurve amplitude small
spectral class L-chondritic (Abell et al., DPS 2005)
Last updated: 2005 September 20
Discovery
M.P.E.C. 1998-S04 Issued 1998 Sept. 17, 15:05 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.
BMARSDEN@CFA.HARVARD.EDU or GWILLIAMS@CFA.HARVARD.EDU
URL http://cfa-www.harvard.edu/iau/mpc.html
1998 RO1
Observations:
J98R01O* C1998 09 14.14870 22 32 54.57 -18 13 44.9 18.6 704
J98R01O C1998 09 14.17064 22 32 46.89 -18 13 53.2 18.5 704
J98R01O C1998 09 14.19260 22 32 39.17 -18 14 03.2 17.9 704
J98R01O C1998 09 14.21469 22 32 31.37 -18 14 11.6 18.0 704
J98R01O C1998 09 15.45961 22 25 20.86 -18 22 08.8 17.3 R 426
J98R01O C1998 09 15.46345 22 25 19.42 -18 22 09.6 17.4 R 426
J98R01O C1998 09 15.46779 22 25 17.87 -18 22 11.6 17.3 R 426
J98R01O C1998 09 15.47130 22 25 16.57 -18 22 12.8 17.2 R 426
J98R01O C1998 09 15.84566 22 23 05.89 -18 24 47.4 587
J98R01O C1998 09 15.84943 22 23 04.60 -18 24 47.5 587
J98R01O C1998 09 15.85271 22 23 03.44 -18 24 49.6 17.9 R 587
J98R01O C1998 09 16.49022 22 19 20.17 -18 27 52.4 18.7 R 422
J98R01O C1998 09 16.49159 22 19 19.68 -18 27 53.1 18.7 R 422
J98R01O C1998 09 16.49295 22 19 19.22 -18 27 53.5 18.8 R 422
J98R01O C1998 09 16.49440 22 19 18.68 -18 27 54.0 18.7 R 422
J98R01O C1998 09 16.53578 22 19 04.15 -18 28 06.8 17.0 R 426
J98R01O C1998 09 16.54032 22 19 02.52 -18 28 08.2 17.2 R 426
J98R01O C1998 09 16.54536 22 19 00.72 -18 28 09.5 17.1 R 426
J98R01O WC1998 09 16.91106 22 16 52.22 -18 30 18.2 557
J98R01O C1998 09 16.94950 22 16 38.45 -18 30 28.0 557
J98R01O C1998 09 17.47302 22 13 35.35 -18 32 19.9 17.3 R 426
J98R01O C1998 09 17.47744 22 13 33.77 -18 32 21.0 17.4 R 426
J98R01O C1998 09 17.48206 22 13 32.05 -18 32 22.6 17.2 R 426
Observer details:
422 Loomberah. Observer G. J. Garradd. 0.45-m f/5.4 reflector + CCD.
426 Woomera. Observer F. B. Zoltowski. 0.30-m f/3.3 Schmidt-Cassegrain + CCD.
557 Ondrejov. Observers P. Pravec, L. Sarounova. 0.65-m f/3.6 reflector
+ CCD.
587 Sormano. Observers P. Sicoli, A. Testa. 0.5-m reflector + CCD.
704 Lincoln Laboratory ETS, New Mexico. Observers M. Blythe, F. Shelly,
M. Bezpalko. Measurers J. Stuart, H. Viggh, R. Sayer. 1.0-m f/2.15
reflector + CCD.
Orbital elements:
1998 RO1
Epoch 1998 Sept. 4.0 TT = JDT 2451060.5 Williams
M 254.38706 (2000.0) P Q
n 0.99784956 Peri. 151.12512 -0.80418120 -0.59185120
a 0.9918043 Node 351.89302 +0.44276566 -0.53496639
e 0.7223360 Incl. 22.87389 +0.39654908 -0.60292879
P 0.99 H 18.0 G 0.15
From 23 observations 1998 Sept. 14-17.
Ephemeris:
1998 RO1 a,e,i = 0.99, 0.72, 23 q = 0.2754
Date TT R. A. (2000) Decl. Delta r Elong. Phase V
1998 09 14 22 33.75 -18 12.4 0.447 1.435 160.4 13.6 17.8
1998 09 19 22 04.62 -18 37.4 0.436 1.399 150.1 21.0 18.0
1998 09 24 21 35.67 -18 36.6 0.434 1.362 139.2 28.8 18.1
1998 09 29 21 08.58 -18 11.3 0.440 1.322 128.5 36.4 18.3
1998 10 04 20 44.45 -17 26.8 0.453 1.279 118.3 43.6 18.5
1998 10 09 20 23.70 -16 29.7 0.470 1.233 108.7 50.1 18.7
1998 10 14 20 06.22 -15 25.5 0.489 1.184 99.9 56.1 18.8
1998 10 19 19 51.60 -14 18.3 0.509 1.132 91.7 61.6 19.0
1998 10 24 19 39.25 -13 10.5 0.528 1.077 84.0 66.8 19.1
1998 10 29 19 28.52 -12 03.7 0.546 1.018 76.8 71.8 19.2
1998 11 03 19 18.67 -10 58.7 0.560 0.955 69.7 76.9 19.3
1998 11 08 19 08.99 -09 56.8 0.572 0.889 62.7 82.4 19.4
1998 11 13 18 58.66 -08 59.6 0.580 0.817 55.6 88.5 19.5
1998 11 18 18 46.76 -08 10.3 0.585 0.742 48.3 95.6 19.6
1998 11 23 18 32.18 -07 34.7 0.589 0.661 40.4 104.3 19.8
Gareth V. Williams (C) Copyright 1998 MPC M.P.E.C. 1998-S04
SNR Calculation
PRIMARY
Target Name: 1998 RO1
HMag: 18.0
Diameter: 0.8 km
Period: 2.492 h
------------GOLDSTONE---------- -------------ARECIBO-----------
Max Max
Dat Run UTC Dat Run UTC
Date RA Decl Delta Runs SNR SNR Window Runs SNR SNR Window
2005 9 11 36 27 0.238 78 1 0 5:24-16:23 17 6 2 6:17- 8:48
2005 9 12 37 29 0.225 83 1 0 5:17-16:30 17 7 2 6:17- 8:41
2005 9 13 37 31 0.212 89 1 0 5:05-16:30 17 8 2 6:24- 8:35
2005 9 14 38 33 0.199 95 1 0 5:00-16:36 16 9 3 6:30- 8:24
2005 9 15 38 36 0.187 103 1 0 4:54-16:41 13 9 3 6:47- 8:05
2005 9 16 39 39 0.175 111 2 0 4:42-16:48 4 9 3 -
2005 9 17 40 42 0.164 121 2 0 4:30-17:00 0 0 0 -
2005 9 18 41 46 0.153 132 3 0 4:24-17:11 0 0 0 -
2005 9 19 43 50 0.143 146 4 0 4:05-17:30 0 0 0 -
2005 9 20 45 55 0.135 163 6 0 3:53-18:00 0 0 0 -
2005 9 21 49 61 0.127 185 7 1 3:30-18:36 0 0 0 -
2005 9 22 54 67 0.121 222 9 1 3:00-19:41 0 0 0 -
2005 9 23 63 73 0.116 346 13 1 1:53-21:53 0 0 0 -
2005 9 24 83 78 0.113 353 15 1 0:00-24:00 0 0 0 -
2005 9 25 124 81 0.112 356 15 1 0:00-24:00 0 0 0 -
2005 9 26 164 78 0.114 353 15 1 0:00-24:00 0 0 0 -
2005 9 27 183 72 0.117 344 13 1 9:48-29:23 0 0 0 -
2005 9 28 191 66 0.121 217 9 1 11:54-28:23 0 0 0 -
2005 9 29 196 60 0.128 183 7 1 12:54-27:53 0 0 0 -
2005 9 30 199 55 0.136 161 5 0 13:30-27:36 0 0 0 -
2005 10 1 201 50 0.145 144 4 0 13:54-27:18 0 0 0 -
2005 10 2 203 46 0.155 131 3 0 14:11-27:06 0 0 0 -
2005 10 3 204 42 0.165 120 2 0 14:24-26:53 0 0 0 -
2005 10 4 205 38 0.177 110 2 0 14:35-26:41 5 5 3 -
2005 10 5 205 35 0.189 102 1 0 14:41-26:30 13 9 3 16:30-18:00
2005 10 6 206 33 0.201 94 1 0 14:48-26:23 16 9 3 16:11-18:11
2005 10 7 206 30 0.214 88 1 0 14:48-26:18 17 8 2 16:06-18:18
2005 10 8 207 28 0.227 82 1 0 14:54-26:06 17 7 2 15:54-18:18
2005 10 9 207 26 0.241 77 1 0 14:54-26:00 17 5 2 15:48-18:23
2005 10 10 207 25 0.255 72 0 0 15:00-25:53 17 5 1 15:41-18:18
SECONDARY
Target Name: 1998 RO1
Diameter: 0.4 km
Period: 14.55 h
2005 9 11 36 27 0.238 78 0 0 5:24-16:23 17 5 1 6:17- 8:48
2005 9 12 37 29 0.225 83 1 0 5:17-16:30 17 6 2 6:17- 8:41
2005 9 13 37 31 0.212 89 1 0 5:05-16:30 17 7 2 6:24- 8:35
2005 9 14 38 33 0.199 95 1 0 5:00-16:36 16 8 2 6:30- 8:24
2005 9 15 38 36 0.187 103 1 0 4:54-16:41 13 8 3 6:47- 8:05
2005 9 16 39 39 0.175 111 2 0 4:42-16:48 4 8 2 -
2005 9 17 40 42 0.164 121 2 0 4:30-17:00 0 0 0 -
2005 9 18 41 46 0.153 132 3 0 4:24-17:11 0 0 0 -
2005 9 19 43 50 0.143 146 4 0 4:05-17:30 0 0 0 -
2005 9 20 45 55 0.135 163 5 0 3:53-18:00 0 0 0 -
2005 9 21 49 61 0.127 185 6 1 3:30-18:36 0 0 0 -
2005 9 22 54 67 0.121 222 8 1 3:00-19:41 0 0 0 -
2005 9 23 63 73 0.116 346 11 1 1:53-21:53 0 0 0 -
2005 9 24 83 78 0.113 353 13 1 0:00-24:00 0 0 0 -
2005 9 25 124 81 0.112 356 13 1 0:00-24:00 0 0 0 -
2005 9 26 164 78 0.114 353 13 1 0:00-24:00 0 0 0 -
2005 9 27 183 72 0.117 344 11 1 9:48-29:23 0 0 0 -
2005 9 28 191 66 0.121 217 8 1 11:54-28:23 0 0 0 -
2005 9 29 196 60 0.128 183 6 1 12:54-27:53 0 0 0 -
2005 9 30 199 55 0.136 161 5 0 13:30-27:36 0 0 0 -
2005 10 1 201 50 0.145 144 4 0 13:54-27:18 0 0 0 -
2005 10 2 203 46 0.155 131 3 0 14:11-27:06 0 0 0 -
2005 10 3 204 42 0.165 120 2 0 14:24-26:53 0 0 0 -
2005 10 4 205 38 0.177 110 2 0 14:35-26:41 5 9 2 -
2005 10 5 205 35 0.189 102 1 0 14:41-26:30 13 8 3 16:30-18:00
2005 10 6 206 33 0.201 94 1 0 14:48-26:23 16 8 2 16:11-18:11
2005 10 7 206 30 0.214 88 1 0 14:48-26:18 17 7 2 16:06-18:18
2005 10 8 207 28 0.227 82 1 0 14:54-26:06 17 6 2 15:54-18:18
2005 10 9 207 26 0.241 77 0 0 14:54-26:00 17 5 1 15:48-18:23
2005 10 10 207 25 0.255 72 0 0 15:00-25:53 17 4 1 15:41-18:18
Arecibo SNRs reflect current transmitter power (1/2 power due to only one klystron).
Goldstone Track Assignments
Goldstone tracks
UT UT PDT
DOY Date TX Window TX Window Duration
--- ---- --------- --------- --------
268 Sep 25 1220-1615 0520-0915 3:55
Uncertainties
From Horizons: 2005 September 19, JPL solution 97 (#obs = 1137, 1996-2005):
Date__(UT)__HR:MN R.A._(a-appar)_DEC. delta POS_3sigma DOP_S-sig DOP_X-sig RT_delay-sig
2005-Sep-20 00:00 * 45.28942 55.14480 0.1345335335 .220272562 0.14 0.49 0.000048
2005-Sep-21 00:00 * 48.50988 60.61793 0.1269144480 .233387527 0.14 0.49 0.000051
2005-Sep-22 00:00 * 53.64291 66.58117 0.1206930978 .244464014 0.14 0.49 0.000056
2005-Sep-23 00:00 * 62.93238 72.77682 0.1160881217 .252301869 0.13 0.48 0.000062
2005-Sep-24 00:00 * 82.78232 78.41297 0.1132919873 .256028042 0.13 0.47 0.000069
2005-Sep-25 00:00 * 124.30219 80.99719 0.1124367120 .255477524 0.13 0.45 0.000077
2005-Sep-26 00:00 * 164.04187 78.00706 0.1135651791 .251302815 0.12 0.43 0.000083
Setups
Initial Setup
We are expecting bandwidths of about 30 Hz and 3 Hz for the primary and secondary.
We'll start with the following 10 usec setup (NOT cw in this case!):
127 x 64 10-usec
----------------
baud 10 usec
code 127
gates 127
FFT 64
CLT ??
ncoh 1
bandwidth 787.4 Hz
resolution 12.3 Hz
TXOFF +120 Hz -> echo will be centered at +10 bins or in bin 32+10 = 42
Other possible ranging setups:
---------------------------------------------------------------------------
127 x 64 11-usec single sample, 5.6-Hz resolution.
baud 11 usec
code 127
gates 127
PRP 1397
FFT 64
CLT 11
ncoh 2
bandwidth 357.9 Hz
resolution 5.59 Hz
TXOFF TBD
-------------------------------------------------------------------------
127 x 64 11-usec single sample, 11.2-Hz resolution
baud 11 usec
code 127
gates 127
PRP 1397
FFT 64
CLT 11
ncoh 1
bandwidth 715.8 Hz
resolution 11.2 Hz
TXOFF +60 -> echo would be centered at +5 bins w/perfect ephemeris
-------------------------------------------------------------------------
127 x 64 7-usec single sample
------------------------------
baud 7 usec
code 127
gates 127
PRP 889
FFT 64
CLT 11
ncoh 1
bandwidth 1124.9 Hz
resolution 17.6 Hz
TXOFF +60 -> echo would be centered at +3.4 bins w/perfect ephemeris
-------------------------------------------------------------------------
127 x 64 1-usec single sample
------------------------------
baud 1 usec
code 127
gates 127
PRP 127
FFT 64
CLT 13 & 14, about evenly divided
ncoh 15
bandwidth 525 Hz
resolution 8.2 Hz
TXOFF +50 -> echo would be centered at +6.1 bins w/perfect ephemeris
-------------------------------------------------------------------------------
0.125-usec ranging setup used in first UY4 track (DOY 213, Aug. 1)
------------------
setup JX1XS001 revised
baud 0.125 usec
code 127
gates 127
FFT 64
ncoh 984
bandwidth 64.016384 Hz
resolution 1.000256 Hz
TXOFF We used 10 Hz, placing COM in cell 32+10=42
Henceforth use 15 Hz, to put COM in 32+15=47
incoh sums 4 looks=> 8 sec/record => expect records per run ~ RTT/8
PFS CLT gate 21
_____________________________________________________________________
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
____________________________________________________________________
Instructions
NOTE: Data should be moved to the appropriate subdirectories in
stealth:/export/data0/rosema/1998RO1/raw/
1998 RO1 POINTING:
OSOD and predicts are at Goldstone on stealth:
/export/data2/osod/ops/1998ro1/PRDX.OUT.s97
/PUNCH.OUT.s97
/EPH.OUT.s97
and have been copied to:
/export/data0/rosema/1998RO1/support/
POINTING
TX Offsets
Date (UTC) DOY hhmmss RA Dec Macro LHA Dec RTT OSOD
2005 09 25 268 110000 145.6841 80.2253 A 112.5 97
2005 09 25 268 120000 147.3877 80.1002 A 112.5
2005 09 25 268 130000 149.0396 79.9667 A 112.6
2005 09 25 268 140000 150.6396 79.8250 A -0.0493 -0.0046 112.6
2005 09 25 268 150000 152.1880 79.6751 A 112.7
2005 09 25 268 160000 153.6857 79.5173 A 112.7
2005 09 25 268 170000 155.1341 79.3519 A 112.8
PRDX.OUT.s97
TRANSMITTER: STATION #14, RECEIVER: STATION #14
RECEIVER U.T. RANGE DOPPLER LHA DEC RA EL
2005 SEP 25 12:20 112.5485580819 -111564.411 284.5826 80.0567 147.944 37.327
2005 SEP 25 12:30 112.5564261371 -112938.202 286.8134 80.0345 148.220 37.712
2005 SEP 25 12:40 112.5643906475 -114316.641 289.0457 80.0122 148.495 38.096
2005 SEP 25 12:50 112.5724519415 -115699.735 291.2794 79.9896 148.768 38.479
2005 SEP 25 13:00 112.5806103476 -117087.482 293.5145 79.9667 149.040 38.861
2005 SEP 25 13:10 112.5888661850 -118479.874 295.7511 79.9437 149.310 39.240
2005 SEP 25 13:20 112.5972197833 -119876.895 297.9891 79.9204 149.579 39.616
2005 SEP 25 13:30 112.6056714662 -121278.522 300.2285 79.8969 149.846 39.988
2005 SEP 25 13:40 112.6142215511 -122684.724 302.4694 79.8731 150.112 40.356
2005 SEP 25 13:50 112.6228703662 -124095.462 304.7118 79.8492 150.377 40.720
2005 SEP 25 14:00 112.6316182192 -125510.692 306.9556 79.8250 150.640 41.077
2005 SEP 25 14:10 112.6404654273 -126930.359 309.2008 79.8005 150.901 41.429
2005 SEP 25 14:20 112.6494122952 -128354.401 311.4474 79.7759 151.161 41.773
2005 SEP 25 14:30 112.6584591360 -129782.750 313.6955 79.7510 151.420 42.110
2005 SEP 25 14:40 112.6676062402 -131215.330 315.9450 79.7259 151.678 42.439
2005 SEP 25 14:50 112.6768539057 -132652.054 318.1959 79.7006 151.934 42.759
2005 SEP 25 15:00 112.6862024155 -134092.832 320.4482 79.6751 152.188 43.069
2005 SEP 25 15:10 112.6956520591 -135537.563 322.7019 79.6493 152.441 43.368
2005 SEP 25 15:20 112.7052031011 -136986.140 324.9571 79.6234 152.693 43.657
2005 SEP 25 15:30 112.7148558114 -138438.446 327.2136 79.5972 152.943 43.933
2005 SEP 25 15:40 112.7246104428 -139894.360 329.4716 79.5708 153.192 44.197
2005 SEP 25 15:50 112.7344672525 -141353.751 331.7309 79.5442 153.440 44.448
2005 SEP 25 16:00 112.7444264705 -142816.481 333.9916 79.5173 153.686 44.686
2005 SEP 25 16:10 112.7544883261 -144282.406 336.2536 79.4903 153.931 44.908
2005 SEP 25 16:20 112.7646530466 -145751.374 338.5171 79.4630 154.174 45.116
GOLDSTONE MASTERLOG
==============================================================================
RCV
file setup runs start -stop osod OFFSET TX Poln
------------------------------------------------------------------------------
Sep 25 (DOY 268)
==============================================================================
RADAR ASTROMETRY
==============================================================================
Dr. Lance A. M. Benner | PHONE: (818) 354-7412
Mail Stop 300-233 | FAX: (818) 354-9476
Jet Propulsion Laboratory | email: lance@reason.jpl.nasa.gov
Pasadena, CA 91109-8099 | Plan: To live long and prosper
http://echo.jpl.nasa.gov/asteroids/1998RO1/html/1998RO1_2005_planning.html
Asteroid Radar Astronomy