Transcript Recent Arecibo Radar Imaging of Near

Arecibo and Goldstone Radar
Imaging of Contact Binary
Near-Earth Asteroids
L. A. M. Benner, M. C. Nolan, J. L. Margot,
S. J. Ostro, M. K. Shepard, C. Magri,
J. D. Giorgini, and M. W. Busch
Outline
1.
2.
3.
4.
5.
6.
7.
Overview of NEAs detected by radar
Updated binary NEA statistics
2005 NB7
(1139) Atami
Smorgasbord of contact binaries
Upcoming NEA radar targets
Historical note
NEAs Detected by Radar
Binary NEAs: Statistics for Radar Targets
OVERALL
Discovered by radar:
Detected by radar
21/33 = 64%
25/33 = 76%
Discovered at Arecibo:
17/33 = 52% (Includes Sisyphus)
Discovered at Goldstone: 4/33 = 12%
Since completion of the upgrade at Arecibo in 1999:
Discovered by radar:
20/25 = 80%
Detected by radar:
23/25 = 92%
Abundance among radar targets: 17%
Arecibo has become the primary technique for discovery
and characterization of binary NEAs.
Binary NEAs Detected by Radar
2000 DP107
2000 UG11
1999 KW4
1998 ST27
2002 BM26
2002 KK8
Sekhmet
1998 RO1
2003 SS84
Hermes
1990 OS
Didymos
1999 DJ4
2003 YT1
2002 CE26
2005 AB
1994 XD
Apollo
2006 GY2
2004 DC
2006 VV2
2007 DT103
2001 SN263
2005 NB7
Sisyphus 1985
2000
2000
2001, 2002
2001, 2004
2002
2002
2003
2003, 2004
2003
2003
2003 (1990)
2003
2004
2004
2004
2005
2005
2005 (1980)
2006
2006
2007
2007
2008
2008
2005 NB7
(1139) Atami
Contact Binary Candidates Detected by Radar
2201
4769
2064
4486
Oljato (?)
Castalia
Bacchus
Mithra
2000 YF29
2002 FC
2002 NY40
141593 2002 HK12
52387 1993 OM7
68346 2001 KZ66
11066 Sigurd
2005 CR37
2004 RF84
2004 XL14
2007 VD12
2007 TU24
2002 TD66
4450 Pan
1983 Jun
1989 Aug
1996 Mar
2000 Jul-Aug
2001 Jan
2002 Jun
2002 Aug
2002 Aug
2003 Jan
2003 Oct
2004 Sep
2005 Feb
2005 Feb
2006 Dec
2007 Nov
2008 Jan-Feb
2008 Feb
2008 Feb
Not included:
3908 Nyx
4179 Toutatis
25143 Itokawa
Abundance: ~11%
among NEAs > 200 m
in diameter
What can we estimate for each?
Object
Oljato
Castalia
Bacchus
Mithra
2000 YF29
2002 FC No
2002 NY40
2002 HK12
1993 OM7
2001 KZ66
Sigurd
2005 CR37
2004 RF84
2004 XL14
2007 VD12
2007 TU24
2002 TD66
Pan
Shape?
No
Available
Available
Maybe
No
Class
S
Maybe
Maybe
No
Yes
Yes
No
No
Not yet
No
No
No
No
S
X
Q
S
S
S
C?
C
S
S
S
S
Returns in December
(2201) Oljato
(4769) Castalia
(2063) Bacchus
(4486) Mithra
2000 YF29
2000 YF29
2002 FC
2002 NY40
Arecibo, Aug. 2002
(141593) 2002 HK12
Arecibo, Aug. 2002
Aug. 23
Aug. 25
(52387) 1993 OM7
Arecibo-Green Bank
2003 Jan 13
2003 Jan 14
(68346) 2001 KZ66
Arecibo, Oct. 2003
(11066) Sigurd
(11066) Sigurd
(11066) Sigurd
(3908) Nyx
2005 CR37
2005 CR37
2004 RF84
2004 XL14
2007 VD12
2007 TU24
2007 TU24
(4450) Pan
Arecibo, Feb. 2008
Feb. 13
Feb. 12
Feb. 14
Upcoming Radar Opportunities:
55319
90403
35107
8567
137032
164400
85774
136849
1999 JM8
2008 BT18
2003 YE45
2005 RC34
1991 VH
2000 DP107
1996 HW1
1998 UO1
2005 GN59
1998 UT18
2004 XL14
2008 EV5
2004 LV3
1998 CS1
May-June
July
July
July
August
September
September
September
October
November
December
December
December
January
A
A, G
A, G
A, G
A, G
A, G
A
A
A, G
A
A
A, G
A
A, G
NEA Radar Detection History
40th anniversary of the 1st asteroid radar detection is in
June: 1566 Icarus by Dick Goldstein at Goldstone