2005 NB7 Goldstone Radar Observations Planning
Background
2005 NB7 was discovered by the Catalina Sky Survey (Univ. of Arizona)
on July 5, 2005. It will approach within 0.0422 AU (16.4 lunar distances)
on April 17 and it should be a strong radar target at Goldstone.
With an absolute magnitude of 18.7, 2005 NB7 has a diameter that is probably
within a factor of two of 570 meters. Otherwise, we know nothing about its
physical properties, but if recent experience is a guide, then there's a
~1/6 chance that it's a binary object.
Update on April 17: Arecibo radar observations on April 10-12 show that
2005 NB7 is a binary and that its components are about 0.5 and 0.2 km
in diameter. The primary's rotation period is > 2.5 h and the average
separation between the two objects is at least 0.6 km. The orbital
period is unknown.
Goldstone observations are scheduled during one track on April 18.
Arecibo observations are scheduled on April 10-12, so by the time
we start observations at Goldstone, we should have a much better understanding
of this object's physical properties.
2005 NB7 will brighten to about 15th magnitude in April
when it will be a good target for lightcurves and spectroscopy.
Due to its diameter and the proximity of its orbit to Earth, 2005 NB7 has been
classified as a "Potentially Hazardous Asteroid" by the Minor Planet Center.
The Principal Investigator for these observations is Dr. Michael Shepard at
Bloomsburg University in Pennsylvania. Lance Benner will be coordinating the
observations remotely from JPL for Dr. Shepard.
Orbital and Physical Characteristics
orbit type Apollo
semimajor axis 2.042 AU
eccentricity 0.516
inclination 12.7°
perihelion distance 0.988 AU
aphelion distance 3.096 AU
absolute magnitude (H) 18.7
diameter 500 meters
rotation period > 2.5 hours
pole direction unknown
lightcurve amplitude unknown
spectral class Sq (M. D. Hicks, personal communication)
BINARY SYSYTEM
Last update: 2008 April 24
Discovery
M.P.E.C. 2005-N32 Issued 2005 July 6, 11:43 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 NB7
Observations:
K05N07B* C2005 07 05.16712 13 36 59.94 +11 47 17.5 20.1 V EN032703
K05N07B C2005 07 05.17352 13 37 01.63 +11 47 09.5 19.9 V EN032703
K05N07B C2005 07 05.17997 13 37 03.36 +11 47 00.7 20.6 V EN032703
K05N07B C2005 07 05.20631 13 37 10.38 +11 46 24.7 19.6 V EN032G96
K05N07B C2005 07 05.20836 13 37 10.92 +11 46 21.9 20.2 V EN032G96
K05N07B C2005 07 05.21042 13 37 11.46 +11 46 18.7 20.0 V EN032G96
K05N07B C2005 07 05.21252 13 37 12.03 +11 46 15.9 20.1 V EN032G96
K05N07B VC2005 07 05.92151 13 40 23.11 +11 30 03.8 20 R EN032204
K05N07B C2005 07 06.13005 13 41 19.17 +11 25 19.4 19.7 R EN032734
K05N07B C2005 07 06.13446 13 41 20.35 +11 25 14.2 20.3 R EN032734
K05N07B C2005 07 06.15954 13 41 26.91 +11 24 42.4 19.9 V EN032703
K05N07B C2005 07 06.16669 13 41 28.93 +11 24 31.8 20.2 V EN032703
K05N07B C2005 07 06.17388 13 41 30.73 +11 24 21.7 19.4 V EN032703
K05N07B C2005 07 06.18107 13 41 32.64 +11 24 12.6 20.3 V EN032703
K05N07B C2005 07 06.22924 13 41 45.32 +11 23 04.9 20.4 R EN032651
K05N07B C2005 07 06.23477 13 41 46.89 +11 22 56.6 20.4 R EN032651
K05N07B C2005 07 06.23698 13 41 47.43 +11 22 54.5 20.4 R EN032651
Observer details:
204 Schiaparelli Observatory. Observer L. Buzzi. 0.60-m f/4.64 Newtonian
reflector + CCD.
651 Grasslands Observatory, Tucson. Observer J. E. McGaha. 0.62-m f/5.1
Newtonian reflector + CCD.
703 Catalina Sky Survey. Observer A. Odell. 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.
734 Farpoint Observatory. Observer W. Leifer. Measurer G. Hug. 0.7-m
reflector + CCD.
G96 Mt. Lemmon 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. 1.5-m reflector + CCD.
Orbital elements:
2005 NB7 PHA 0.013
Epoch 2005 June 19.0 TT = JDT 2453540.5 MPC
M 12.23019 (2000.0) P Q
n 0.28546771 Peri. 356.58670 -0.97286407 +0.22283209
a 2.2843609 Node 196.69027 -0.20681622 -0.95820442
e 0.5509660 Incl. 12.52852 -0.10374272 -0.17941615
P 3.45 H 18.7 G 0.15
From 17 observations 2005 July 5-6.
Ephemeris:
2005 NB7 a,e,i = 2.28, 0.55, 13 q = 1.0258
Date TT R. A. (2000) Decl. Delta r Elong. Phase V
2005 06 29 13 07.92 +14 05.2 0.618 1.213 92.5 56.9 20.1
2005 07 09 13 53.85 +10 19.8 0.685 1.278 95.3 52.4 20.3
2005 07 19 14 33.76 +06 34.1 0.769 1.347 97.0 48.5 20.6
2005 07 29 15 08.66 +03 03.4 0.869 1.419 97.4 45.2 20.9
2005 08 08 15 39.72 -00 05.7 0.984 1.493 96.7 42.4 21.2
2005 08 18 16 07.93 -02 50.6 1.110 1.568 95.1 40.0 21.5
2005 08 28 16 34.01 -05 11.4 1.248 1.643 92.8 37.9 21.8
Timothy B. Spahr (C) Copyright 2005 MPC M.P.E.C. 2005-N32
SNR Calculation
Target Name: 2005NB7
HMag: 18.7
Diameter: 0.570 (an educated guess assuming H = 18.7 and an S-class optical albedo)
Period: 4 (a standard guess)
------------GOLDSTONE---------- -------------ARECIBO-----------
Max Max
Dat Run UTC Dat Run UTC
Date RA Decl Delta Runs SNR SNR Window Runs SNR SNR Window
2008 4 4 93 -1 0.091 171 18 2 20:53-29:30 19 180 44 21:30-22:11
2008 4 5 94 1 0.085 184 23 2 20:48-29:36 29 320 66 21:11-22:30
2008 4 6 95 3 0.080 199 30 2 20:41-29:41 38 520 96 21:00-22:41
2008 4 7 96 5 0.075 216 40 3 20:36-29:48 47 770 120 20:48-22:48
2008 4 8 97 8 0.070 235 53 4 20:30-29:53 55 1100 160 20:41-23:00
2008 4 9 99 11 0.065 256 71 5 20:23-30:06 64 1500 200 20:36-23:06
2008 4 10 100 14 0.061 281 96 6 20:18-30:18 72 2100 260 20:36-23:11
2008 4 11 102 18 0.057 309 130 8 20:11-30:30 78 2800 330 20:36-23:18
2008 4 12 105 23 0.053 341 170 10 20:06-30:48 83 3700 430 20:41-23:23
2008 4 13 108 28 0.049 376 230 13 20:00-31:11 81 4500 540 21:00-23:23
2008 4 14 111 34 0.046 414 290 16 19:53-31:36 66 4500 640 21:30-23:18
2008 4 15 116 40 0.044 455 360 19 19:48-32:12 0 0 0 -
2008 4 16 122 47 0.043 496 430 21 19:48-32:53 0 0 0 -
2008 4 17 131 53 0.042 538 470 22 19:53-33:47 0 0 0 -
2008 4 18 142 59 0.043 578 470 22 20:06-34:53 0 0 0 -
2008 4 19 156 63 0.044 611 430 20 20:30-36:12 0 0 0 -
2008 4 20 172 65 0.046 623 370 17 21:18-37:36 0 0 0 -
2008 4 21 189 66 0.049 600 300 14 22:11-38:36 0 0 0 -
2008 4 22 203 65 0.052 549 230 11 23:18-39:17 0 0 0 -
2008 4 23 214 63 0.056 494 170 8 0:12-15:41 0 0 0 -
2008 4 24 222 60 0.060 444 120 7 1:00-16:00 0 0 0 -
2008 4 25 228 58 0.064 401 92 5 1:30-16:06 0 0 0 -
Track Assignments
Goldstone Schedule
UT UT PDT Duration Round-trip
DOY Date TX Window TX Window hh:mm time (sec)
--- ---- --------- --------- ------- ---------
109 Apr 18 0905-1130 0205-0430 Apr 18 02:25 43
Arecibo Schedule
101 Apr 10 2036-2322 1636-1922 Apr 18 02:46 57
102 Apr 11 2042-2326 1642-1926 Apr 18 02:44 53
103 Apr 12 2056-2327 1656-1927 Apr 18 02:31 49
Uncertainties
From Horizons, 2008 March 31 JPL Solution #24, # obs: 100 (2002-2008)
Date__(UT)__HR:MN R.A._(J2000.0)_DEC. delta POS_3sigma DOP_S-sig DOP_X-sig RT_delay-sig
deg deg AU arcsec Hz Hz sec
2008-Apr-10 00:00 100.476 14.399 0.06072 6.01 0.30 1.06 0.003464
2008-Apr-11 00:00 102.447 18.354 0.05649 7.24 0.29 1.05 0.003337
2008-Apr-12 00:00 104.831 22.894 0.05261 8.71 0.29 1.04 0.003171
2008-Apr-13 00:00 107.769 28.062 0.04919 10.41 0.30 1.06 0.002957
2008-Apr-14 00:00 111.462 33.850 0.04633 12.29 0.32 1.13 0.002686
2008-Apr-15 00:00 116.208 40.153 0.04415 14.18 0.35 1.26 0.002354
2008-Apr-16 00:00 122.442 46.724 0.04274 15.86 0.41 1.46 0.001968
2008-Apr-17 00:00 130.761 53.137 0.04219 17.06 0.48 1.70 0.001548
2008-Apr-18 00:00 141.852 58.801 0.04254 17.60 0.55 1.97 0.001141
2008-Apr-19 00:00 156.068 63.047 0.04376 17.45 0.62 2.22 0.000827
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
From Jon Giorgini, 2008 April 15:
Incorporating the new delay and Doppler from Mike^2 & Arecibo,
along with new optical, 2005 NB7 solution #28 was computed.
Formal 3-sigma X-band uncertainties are as shown below.
Date__(UT)__HR:MN POS_3sigma DOP_X-sig RT_delay-sig
2008-Apr-17 00:00 1.32464209 1.04 0.000138
2008-Apr-18 00:00 1.29221808 1.15 0.000167
2008-Apr-19 00:00 1.23559859 1.23 0.000193
2008-Apr-20 00:00 1.16883454 1.29 0.000215
OSOD and soln. #28 nominal predicts have been established on stealth
for the April 18 track.
Setups
Arecibo observations on April 10-12 showed that NB7 has diameter of about 500 meters and that it's a
a relatively rapid rotator. We're expecting a bandwidth of about 14 Hz, so we will start with a CW
setup with 0.5 Hz resolution in order to resolve the echo in frequency:
Initial 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: 8192 for 0.49-Hz resolution
Possible 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 1
bandwidth 787.4 Hz
resolution 12.3 Hz
TXOFF +100 Hz -> echo will be centered at +8 bins or in bin 32 + 8 = 40
---------------------------------------------------------------------------
127 x 64 11-usec single sample
baud 11 usec
code 127
gates 127
PRP 1397 usec
FFT 64
CLT VME ?
PFS ?
ncoh 1
bandwidth 715.8 Hz
resolution 11.2 Hz
TXOFF +100 Hz --> echo will be centered at +9 bins or in bin 32 + 9 = 41
-------------------------------------------------------------------------
127 x 64 7-usec single sample
baud 7 usec
code 127
gates 127
PRP 889
FFT 64
CLT VME ?
PFS ?
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 4
ncoh 15
bandwidth 525 Hz
resolution 8.2 Hz
TXOFF +100 -> echo would be centered at +12.2 bins or in bin 32 + 12.2 = 44
-------------------------------------------------------------------------------
0.125-usec ranging
setup JX1XS001 revised
baud 0.125 usec
code 127
gates 127
FFT 64
ncoh 984
bandwidth 64.016384 Hz
resolution 1.000256 Hz
TXOFF +15 Hz to put echo at 32 + 15 = bin 47
PFS CLT gate ?
VME CLT gate ?
_______________________________________________________________________
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
aardvark:/export/data0/2005NB7/
2005 NB7 POINTING:
OSOD and predicts are at Goldstone on aardvark:
/export/data3/ops/2005nb7/ PRDX.OUT.s28
/PUNCH.OUT.s28
/EPH.OUT.s28
POINTING
TX Offsets
Date (UTC) DOY hhmmss RA Dec Macro LHA Dec RTT OSOD
2008 04 18 109 090000 146.8169 60.5454 A 42.8 28
2008 04 18 109 100000 147.3937 60.7206 A 42.9
2008 04 18 109 110000 147.9820 60.8929 A -7.1 2.1 42.9
2008 04 18 109 120000 148.5814 61.0631 A 43.0
2008 04 18 109 130000 149.1913 61.2315 A 43.0
Note: in this macro LHA and Dec are given in millidegrees.
PRDX.OUT.s28
TRANSMITTER: STATION #14, RECEIVER: STATION #14
RECEIVER U.T. RANGE DOPPLER LHA DEC RA EL
2008 APR 18 09:00 42.8170453093 -120037.886 78.1432 60.5454 146.817 35.948
2008 APR 18 09:10 42.8254819869 -120685.585 80.5547 60.5748 146.912 34.790
2008 APR 18 09:20 42.8339634239 -121314.940 82.9658 60.6041 147.008 33.642
2008 APR 18 09:30 42.8424883277 -121925.917 85.3767 60.6334 147.104 32.505
2008 APR 18 09:40 42.8510554101 -122518.512 87.7872 60.6625 147.200 31.381
2008 APR 18 09:50 42.8596633885 -123092.753 90.1975 60.6916 147.297 30.270
2008 APR 18 10:00 42.8683109785 -123648.701 92.6074 60.7206 147.394 29.174
2008 APR 18 10:10 42.8769968958 -124186.447 95.0170 60.7495 147.491 28.094
2008 APR 18 10:20 42.8857198739 -124706.114 97.4263 60.7783 147.589 27.031
2008 APR 18 10:30 42.8944786432 -125207.856 99.8352 60.8071 147.686 25.985
2008 APR 18 10:40 42.9032719614 -125691.857 102.2439 60.8357 147.785 24.958
2008 APR 18 10:50 42.9120985897 -126158.330 104.6522 60.8644 147.883 23.951
2008 APR 18 11:00 42.9209573055 -126607.522 107.0602 60.8929 147.982 22.964
2008 APR 18 11:10 42.9298469069 -127039.704 109.4679 60.9214 148.081 21.999
2008 APR 18 11:20 42.9387662173 -127455.178 111.8753 60.9499 148.181 21.057
2008 APR 18 11:30 42.9477140769 -127854.273 114.2824 60.9782 148.280 20.139
2005 NB7 GOLDSTONE MASTERLOG
==============================================================================
Receive TX
Setup hops dwell code ncoh FFT runs start -stop OSOD offset Poln Notes
------------------------------------------------------------------------------
2008 April 18
PSD.2008109.260.2005NB7, PSD.2008109.261.2005NB7, VOLT.2008109.262.2005NB7
CW, 4 kHz 2 20 4096 10 091231-092624 28 none RCP BAD POINTING MACRO--NO ECHOES
PSD.2008109.258.2005NB7, VOLT.2008109.259.2005NB7
CW, 4 kHz 2 20 4096 8 094729-095827 28 none RCP Good pointing macro
PSD.2008109.256.2005NB7, VOLT.2008109.257.2005NB7
CW, 4 kHz 2 20 8192 11 095915-101436 28 none RCP
0.25 usec 127 492 128 24 105522-112947 28 +16 Hz RCP
Weighted sum of all 24 0.25 usec x 0.25 Hz runs:
Collage showing weighted sums of 8 runs/frame:
CW spectrum with a frequency resolution of 0.24 Hz
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/2005NB7/2005NB7_planning.html
Asteroid Radar Astronomy