Contact binary asteroids, TNOs, and comets (original) (raw)

compiled by Wm. Robert Johnston
last updated 3 June 2024

Of those asteroids for which shapes have been determined, a number have bilobated or contact binary shapes. These objects likely relate to true binary asteroids (i.e. with physically separated components) in origin.

The following table lists 122 known and suspected contact binary solar system objects: 73 near-Earth asteroids, 15 main belt asteroids, 1 asteroid satellite, 2 Jupiter trojan asteroids, 24 trans-Neptunian objects, and 7 comets. "Method" column indicates method used to determine shape; "morphology" column indicates reported comments on shape.

Selam, the satellite of (152830) Dinkinesh, has a bilobated shape but is not in rotational equilibrium as a typical contact binary.

In general those identified by imagery or radar are confident while those identified by lightcurve or other methods are unconfirmed.

This table does not include a number of asteroids that are known or believed to be genuine binaries, with two distinct components, but with very small separations. These include: near-Earth asteroids (5143) Heracles, (363067) 2000 CO101, (374851) 2006 VV2, and (488453) 1994 XD; main belt asteroid (11264) Claudiomaccone; Jupiter trojans (17365) Thymbraeus and (29314) Eurydamas; and trans-Neptunian object (139775) 2001 QG298.

object dynamicaltype status dimensions (km) rotationperiod (h) morphology detectionmethod datereported source known or suspectedcompanions
number name prov. des. A B C
92 Undina main belt asteroid 121 15.941 radar 2010 S15e
104 Klymene A868 RB main belt asteroid unconfirmed 137 8.984 AO imagery 2006 Nov M06d
110 Lydia main belt asteroid 83 10.927 radar 2008 S15e
121 Hermione main belt asteroid 250 120 120 5.55128 AO imagery 2005 M02e, M05i 1 known
129 Antigone main belt asteroid 130 4.95717 radar/lightcurve 2010 S15e 1 suggested
201 Penelope main belt asteroid 105 72 62 3.7474 radar/lightcurve 2015 S15e
216 Kleopatra main belt asteroid 217 94 81 5.38528 dog bone radar 2000 O00a, M08f 2 known
234 Barbara A883 PA main belt asteroid unconfirmed 37 26.4744 thermal 2009 Apr 01 D09d
413 Edburga 1896 CL main belt asteroid 46 29 25 15.773 radar/lightcurve 2015 S15e
624 Hektor 1907 XM Jupiter trojan asteroid unconfirmed 416 131 120 6.921 lightcurve 1978 H78a, M06c, D15a 1 known
678 Fredegundis 1909 FS main belt asteroid 40 11.61624 radar 2008 S08d
758 Mancunia 1912 PE main belt asteroid 89 12.7253 radar 2006 S10c
779 Nina 1914 UB main belt asteroid 81 11.186 radar 2008 S15e
1333 Cevenola 1934 DA main belt asteroid unconfirmed 16 4.88 lightcurve 2012 Oct 02 M12c
1981 Midas 1973 EA Apollo asteroid 3.4 1.9 1.3 5.22 bilobated radar 2018 B18r, B21n, M22b
2063 Bacchus 1977 HB Apollo asteroid 1.11 0.53 0.5 14.904 radar 1997 Jul B97b, B99a
3169 Ostro 1981 LA main belt asteroid unconfirmed 4.6 1.7 1.6 6.509 lightcurve 2007 Apr 04 D07b, D07b 1 known
3623 Chaplin 1981 TG2 main belt asteroid unconfirmed 11 8.361 lightcurve 2012 Oct 02 M12c
3752 Camillo 1985 PA Apollo asteroid 2.3 37.846 radar 2018 B18r
4179 Toutatis 1989 AC Apollo asteroid 4.26 2.03 1.70 176 bilobated radar 1992 H95a, JPL
4450 Pan 1987 SY Apollo asteroid 1.0 56.48 radar 2008 B16d
4486 Mithra 1987 SB Apollo asteroid 2.35 1.65 1.44 67.5 radar 2000 Oct O00b, B10c
4769 Castalia 1989 PB Apollo asteroid 1.7 1.0 1.0 4.095 radar 1989 Nov 21 O90a
5836 1993 MF Amor asteroid unconfirmed 2.8 4.9543 lightcurve 2017 B17h
8567 1996 HW1 Amor asteroid 3.78 1.64 1.49 8.7573 radar 2011 M11f
11066 Sigurd 1992 CC1 Apollo asteroid 4.2 ~2 ~2 8.4958 radar 2004 Dec B04f, B12g
13553 Masaakikoyama 1992 JE Amor asteroid ~2 0.8 58 radar 2022 V22a
19521 Chaos 1998 WH24 TNO/cubewano ~520 occultation 2023 Jul 11 G23a
25143 Itokawa 1998 SF36 Apollo asteroid 0.535 0.294 0.209 12.132 bilobated SC imagery 2005 D06b
26308 1998 SM165 TNO/1:2 resonance unconfirmed 270 8.4 lightcurve 2004 May S04d
47932 2000 GN171 TNO/Plutino unconfirmed 147 8.329 lightcurve 2002 Sep S02a
52387 Huitzilopochtli 1993 OM7 Amor asteroid 0.89 >26 radar 2003 B16d
66652 Borasisi 1999 RZ253 TNO/cubewano unconfirmed 126 dynamical 2023 P23d 1 known
68346 2001 KZ66 Apollo asteroid 1.51 0.64 0.78 4.98599 radar 2003 B16d, Z21a
85989 1999 JD6 Aten asteroid 3.0 1.2 1.0 7.66435 peanut radar 2014 W14f, D24a
85990 1999 JV6 Apollo asteroid 0.73 0.37 0.35 6.53678 bilobated radar 2016 B16d, R19a
90403 2003 YE45 Apollo asteroid 1.0 0.5 0.5 505 bilobated radar 2022 V22a
96590 1998 XB Aten asteroid 0.9 520 radar 2017 B17h
99942 Apophis 2004 MN4 Aten asteroid 0.43 0.30 0.26 30.56 radar 2015 B15i
118378 1999 HT11 TNO unconfirmed ~160 >3.5 lightcurve 2023 Dec 13 T24a
126719 2002 CC249 TNO unconfirmed ~210 11.87 lightcurve 2017 T17c
137126 1999 CF9 Apollo asteroid 0.9 6.7 radar 2013 B15h
141593 2002 HK12 Apollo asteroid 0.6 12.69 radar 2002 B15h
143404 2003 BD44 Apollo asteroid ~1.3 78.64 radar 2017 B17h
144411 2004 EW9 Apollo asteroid 2 1 1 49.94 radar 2012 B16d
152664 1998 FW4 Apollo asteroid 0.3 17.38 radar 2009 B16d
152830 (Dinkinesh) (1999 VD57) main belt asteroid moon confirmed 0.22 bilobated SC imagery 2023 Nov 03 K23b companion
153201 2000 WO107 Aten asteroid 0.82 0.38 5.022 radar 2020 B20a
163696 2003 EB50 Apollo asteroid 1.6 62.06 peanut radar 2015 B16d
179806 2002 TD66 Apollo asteroid 0.3 9.455 radar 2008 B16d
192642 1999 RD32 Apollo asteroid 5 17.08 radar 2012 B16d
231937 2001 FO32 Apollo asteroid 1.2 ~0.5 ~0.5 39.905 peanut radar 2021 B21n
242191 2003 NZ6 Aten asteroid 0.6 0.3 0.3 13.531 radar 2015 B16d
242643 2005 NZ6 Apollo asteroid 1.99 7 radar 2013 B15h
275677 2000 RS11 Apollo asteroid 0.698 0.578 0.758 4.444 radar 2014 B15h
348306 2005 AY28 Aten asteroid 0.09 6.292 radar 2014 B15h
349507 2008 QY Apollo asteroid ~0.5 bifurcated radar 2023 B23x
367789 2011 AG5 Apollo asteroid 0.5 0.15 9.4357 bilobated radar 2022 B23f, N23b
385446 Manwe 2003 QW111 TNO/4:7 resonance unconfirmed 160 11.8819 dynamical 2020 Jan T19c, R20d 1 known
385458 2003 SP317 TNO/cubewano unconfirmed ~160 12.39 lightcurve 2024 Feb 07 T24a
388188 2006 DP14 Apollo asteroid 0.4 0.2 0.2 5.7868 radar 2014 J14a
398188 Agni 2010 LE15 Aten asteroid 0.46 21.99 radar 2015 B15h
413260 2003 TL4 Aten asteroid 0.31 27.2 radar 2017 B17h
418135 2008 AG33 Apollo asteroid 0.33 radar 2022 B22t
434709 2006 CJ69 TNO unconfirmed ~140 23.39 lightcurve 2023 Dec 13 T24a
436774 2012 KY3 Apollo asteroid ~0.4 ~0.25 radar 2023 B23v
438661 2008 EP6 Apollo asteroid 0.31 5 radar 2016 B16d
443880 2001 UZ16 Apollo asteroid 0.23 13.719 radar 2016 B16d
462959 2011 DU Apollo asteroid 0.2 10.29 radar 2017 B17h
481394 2006 SF6 Aten asteroid 0.32 0.12 11.4876 radar 2020 Z20a, V22a
481817 2008 UL90 Atira asteroid ~0.6 radar 2017 B17h
486958 Arrokoth 2014 MU69 TNO/cubewano 35 20 10 15.918 bilobated and lenticular occultation, imaging 2017 Aug 03 N17a, S19a
494999 2010 JU39 Aten asteroid >0.16 ~0.1 30.2 radar 2022 V22a
496817 1989 VB Apollo asteroid ~0.3 14.533 radar 2017 B17h
503941 2003 UV11 Apollo asteroid 0.26 18.25 radar 2010 B16d
511684 2015 BN509 Apollo asteroid 0.32 5.6713 radar 2017 B17h
523804 2000 YF29 Apollo asteroid 0.2 <12 radar 2001 B12g
524522 Zoozve 2002 VE68 Aten asteroid unconfirmed ~0.26 13.50 lightcurve 2011 May B11d
524594 2003 NW1 Apollo asteroid 0.7 0.35 37.7 radar 2022 V22a
525268 2004 XL14 Aten asteroid 0.17 24 radar 2006 B12g
531074 2012 DX98 TNO/resonant unconfirmed ~150 20.8 lightcurve 2019 T19c, T22a
531917 2013 BN82 TNO unconfirmed ~200 18.22 lightcurve 2023 Dec 13 T24a
532039 2013 FR28 TNO/resonant unconfirmed ~150 lightcurve 2019 T19c
533562 2014 JQ80 TNO/Plutino unconfirmed ~165 ~83 ~63 12.16 lightcurve 2018 T18a
543734 2014 OL394 TNO unconfirmed ~120 >4 lightcurve 2023 Dec 13 T24a
554292 2012 TC24 Jupiter trojan asteroid unconfirmed ~4.5 lightcurve 2018 D18a
578992 2014 JL80 TNO/Plutino unconfirmed ~150 34.87 lightcurve 2018 T18a
609221 2004 VC131 TNO/cubewano unconfirmed ~270 15.7 lightcurve 2019 T19c
612342 2002 FC Apollo asteroid 0.7 >40 radar 2002 B15h
612620 2003 SQ317 TNO/Haumea family unconfirmed ~380 ~190 ~180 7.210 lightcurve 2013 Sep 06 L13a
612813 2004 RF84 Apollo asteroid 2.2 >300 radar 2005 B15h
612891 2004 TT357 TNO/2:5 resonance unconfirmed ~140 ~70 ~50 7.79 lightcurve 2017 Jul 31 T17d/d
612929 2005 CR37 Apollo asteroid 1.8 0.8 0.8 5.6 radar 2006 B06f
671294 2014 JO25 Apollo asteroid 0.87 0.65 4.5286 peanut radar 2017 Apr 17 N17b
2002 AY1 Aten asteroid ~0.2 8 radar 2013 B15h
2002 NY40 Apollo asteroid 0.4 19.98 radar 2002 T12d
2004 MU8 TNO/cubewano unconfirmed ~180 >2.5 lightcurve 2019 T19c, G19c
2004 SC60 TNO unconfirmed ~160 58.09 lightcurve 2023 Dec 13 T24a
2004 VE131 TNO unconfirmed ~130 >8 lightcurve 2023 Dec 13 T24a
2004 VU75 TNO/cubewano unconfirmed ~210 >3 lightcurve 2019 T19c
2007 TU24 Apollo asteroid 0.3 26 radar 2008 B16d
2007 VD12 Apollo asteroid 0.18 7.418 radar 2007 B16d
2008 SV11 Apollo asteroid 0.8 32.4 radar 2009 B16d
2009 DL46 Apollo asteroid 0.1 42.26 radar 2017 B17h
2010 GT7 Apollo asteroid 0.32 0.22 ~16 radar 2022 V22a
2012 MS4 Apollo asteroid 0.48 0.25 <42 radar 2022 V22a
2012 QG42 Apollo asteroid 0.25 24.22 radar 2013 B16d
2013 JB36 Amor asteroid ~0.25 radar 2013 H13c
2013 JR28 Apollo asteroid 0.1 >10 radar 2013 B15h
2014 HQ124 Aten asteroid 0.325 >16 radar 2014 B15h
2014 JO80 TNO/Plutino unconfirmed ~113 ~66 ~47 6.32 lightcurve 2018 T18a
2014 UF206 Amor asteroid 1.39 6.83 radar 2015 B15h
2015 JD1 Apollo asteroid 0.15 0.1 0.1 5.2116 radar 2020 L20b, L22a
2017 BW Apollo asteroid 0.05 14.559 radar 2017 B17h
2021 LD1 Apollo asteroid ~0.9 radar 2021 B21o
1P Halley P/1682 Q1 Halley family comet 15.1 8.0 7.7 54 peanut SC imagery 1986 S91b
8P Tuttle P/1858 A1 Jupiter family comet 10.0 5.75 4.11 11.385 radar 2010 H10b
19P Borrelly P/1904 Y2 Jupiter family comet 4.4 1.8 26 SC imagery 2002 S04d
45P Honda-Mrkos-Pajdusakova P/1948 X1 Jupiter family comet 1.3 7.6 radar 2017 U17a
67P Churyumov-Gerasimenko P/1969 R1 Jupiter family comet 4.1 4.1 3.3 12.76137 rubber ducky SC imagery 2014 S15f
103P Hartley 2 P/1986 E2 Jupiter family comet 2.3 ~0.8 18.236 bilobated SC imagery 2011 H11c, T13b
331P-A Gibbs 14 P/2012 F5-A comet/active asteroid unconfirmed 0.8 3.26 symmetric lightcurve 2021 J21a

Specific sources: see this page.

General sources:

© 2002-2023, 2024 by Wm. Robert Johnston.
Last modified 3 June 2024.
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