Minor-planet moon explained

See also: Binary asteroid.

A minor-planet moon is an astronomical object that orbits a minor planet as its natural satellite., there are 457 minor planets known or suspected to have moons. Discoveries of minor-planet moons (and binary objects, in general) are important because the determination of their orbits provides estimates on the mass and density of the primary, allowing insights into their physical properties that are generally not otherwise accessible.

Several of the moons are quite large compared to their primaries: 90 Antiope, Mors - Somnus and Sila - Nunam (95%), Patroclus - Menoetius, Altjira and Lempo - Hiisi (90%, with Lempo - Paha at 50%). The largest known minor-planet moon in absolute size is Pluto's largest moon Charon, which itself has about half the diameter of Pluto.

There are also several known ring systems around distant objects (see: Rings of Chariklo and Chiron).

Terminology

See also: Binary asteroid.

In addition to the terms satellite and moon, the term "binary" (binary minor planet) is sometimes used for minor planets with moons, and "triple" for minor planets with two moons. If one object is much bigger it can be referred to as the primary and its companion as secondary. The term double asteroid is sometimes used for systems in which the asteroid and its moon are roughly the same size, while binary tends to be used independently from the relative sizes of the components. When binary minor planets are similar in size, the Minor Planet Center (MPC) refers to them as "binary companions" instead of referring to the smaller body as a satellite. A good example of a true binary is the 90 Antiope system, identified in August 2000. Small satellites are often referred to as moonlets.

Discovery milestones

Prior to the era of the Hubble Space Telescope and space probes reaching the outer Solar System, attempts to detect satellites around asteroids were limited to optical observations from Earth. For example, in 1978, stellar occultation observations were claimed as evidence of a satellite for the asteroid 532 Herculina. However, later more-detailed imaging by the Hubble Telescope did not reveal a satellite, and the current consensus is that Herculina does not have a significant satellite. There were other similar reports of asteroids having companions (usually referred to as satellites) in the following years. A letter by astronomer Thomas Hamilton in the Sky & Telescope magazine at this time pointed to apparently simultaneous impact craters on Earth (for example, the Clearwater Lakes in Quebec), suggesting that these craters were caused by pairs of gravitationally bound objects.

Also in 1978, Pluto's largest moon Charon was discovered; however, at the time Pluto was still considered to be one of the major planets.

In 1993, the first asteroid moon was confirmed when the Galileo probe discovered the small Dactyl orbiting 243 Ida in the asteroid belt. The second was discovered around 45 Eugenia in 1998. In 2001, 617 Patroclus and its same-sized companion Menoetius became the first known binary asteroids in the Jupiter trojans. The first trans-Neptunian binary after Pluto–Charon,, was optically resolved in 2002.

Multiple systems

In 2005, the asteroid 87 Sylvia was discovered to have two satellites, making it the first known triple system (also called trinary minor planets). This was followed by the discovery of a second moon orbiting 45 Eugenia. Also in 2005, the dwarf planet was discovered to have two moons, making it the second trans-Neptunian object after Pluto known to have more than one moon. Additionally, 216 Kleopatra and 93 Minerva were discovered to be trinary asteroids in 2008 and 2009 respectively. Since the first few triple minor planets were discovered, more continue to be discovered at a rate of about one a year. Most recently discovered were two moons orbiting large near-earth asteroid 3122 Florence, bringing the number of known multiple systems in the Solar System up to 16 (including the Pluto and Haumea systems).

The following table lists all satellites of multiple systems, starting with Pluto, which was unnumbered when its first moon was discovered in 1978. The highest known multiplicities are for Pluto (a sextuple system) and 130 Elektra (a quadruple system).

Parent body	Minor-planet moon
Designation	Orbital class	Designation	Discovery date	Announcement date	Announcement of trinary
		Charon	1978/06/22	1978/07/07	2005/10/31
		Nix	2005/05/15	2005/10/31
		Hydra
		Kerberos	2011/06/28	2013/07/02
		Styx	2012/06/26	2013/07/02
		Petit-Prince	1998/11/01	1999/03/20	2007/03/07
		S/2004 (45) 1	2004/02/14	2007/03/07
	Asteroid belt	Romulus	2001/02/18	2005/08/11	2005/08/11
		Remus	2004/08/09
	Asteroid belt	Aegis	2009/08/16	2013/12/17	2013/12/17
		Gorgoneion
	Asteroid belt	S/2001 (107) 1	2001/03/01	2001/03/19	2016/08/07
		S/2016 (107) 1	2015/05/29	2016/08/07
	Asteroid belt	S/2003 (130) 1	2003/08/15	2003/08/17	2014/12/16
		S/2014 (130) 1	2014/12/06	2014/12/16
		S/2014 (130) 2	2014/12/09	2021/11/06
	Asteroid belt	Alexhelios	2008/09/19	2011/02/18	2011/02/18
		Cleoselene
		S/2009 (2577) 1	2009/02/28	2009/03/11	2013/12/22
		S/2012 (2577) 1	2012/06/22	2013/12/22
		S/2017 (3122) 1	2017/08/29	2017/09/01	2017/09/01
		S/2017 (3122) 2
	Asteroid belt	S/2002 (3749) 1	2002/02/08	2002/02/13	2008/03/12
		S/2007 (3749) 1	2007/07/15	2008/03/12
	Asteroid belt	S/2015 (3666) 1	2015/09/02	2015/10/??	2018/07/20
		S/2015 (3666) 2	2015/09/02	2018/07/20
	Asteroid belt	S/2017 (6186) 1	2017/01/01	2017/01/14	2017/01/14
		S/2017 (6186) 2
	Kuiper belt	Paha	2001/12/08	2002/01/10	2009/10/??
		Hiisi	2009/10/??	2009/10/??
	Kuiper belt	Hiʻiaka	2005/01/26	2008/09/17	2008/09/17
		Namaka	2005/06/30
		Beta (unofficial)	2009/06/12	2009/06/19	2009/06/19
		Gamma (unofficial)
		Beta (unofficial)	2008/02/12	2008/02/12	2008/02/12
		Gamma (unofficial)

Commonality

The data about the populations of binary objects are still patchy. In addition to the inevitable observational bias (dependence on the distance from Earth, size, albedo and separation of the components) the frequency appears to be different among different categories of objects. Among asteroids, an estimated 2% would have satellites. Among trans-Neptunian objects (TNOs), an estimated 11% are thought to be binary or multiple objects, and the majority of the large TNOs have at least one satellite, including all four IAU-listed dwarf planets.

More than 50 binaries are known in each of the main groupings: near-Earth asteroids, belt asteroids, and trans-Neptunian objects, not including numerous claims based solely on light-curve variation.

Two binaries have been found so far among centaurs with semi-major axes smaller than Neptune. Both are double ring systems around 2060 Chiron and 10199 Chariklo, discovered in 1993–2011 and 2013 respectively.

Origin

The origin of minor-planet moons is not currently known with certainty, and a variety of hypotheses exist. One such model is that minor-planet moons are formed from debris knocked off the primary by an impact. Other pairings may be formed when a small object is captured by the gravity of a larger one.

Formation by collision is constrained by the angular momentum of the components, i.e. by the masses and their separation. Close binaries fit this model (e.g. Pluto–Charon). Distant binaries however, with components of comparable size, are unlikely to have followed this scenario, unless considerable mass has been lost in the event.

The distances of the components for the known binaries vary from a few hundreds of kilometres (243 Ida, 3749 Balam) to more than 3000 km (379 Huenna) for the asteroids. Among TNOs, the known separations vary from 3,000 to 50,000 km.

Populations and classes

What is "typical" for a binary system tends to depend on its location in the Solar System (presumably because of different modes of origin and lifetimes of such systems in different populations of minor planets).

• Among near-Earth asteroids, satellites tend to orbit at distances of the order of 3–7 primary radii, and have diameters two to several times smaller than the primary. Since these binaries are all inner-planet crossers, it is thought that tidal stresses that occurred when the parent object passed close to a planet may be responsible for the formation of many of them, although collisions are thought to also be a factor in the creation of these satellites.
• Among main-belt asteroids, the satellites are usually much smaller than the primary (a notable exception being 90 Antiope), and orbit around 10 primary radii away. Many of the binary systems here are members of asteroid families, and a good proportion of satellites are expected to be fragments of a parent body whose disruption after an asteroid collision produced both the primary and satellite.

• Among trans-Neptunian objects, it is common for the two orbiting components to be of comparable size, and for the semi-major axis of their orbits to be much larger − about 100 to 1000 primary radii. A significant proportion of these binaries are expected to be primordial.
  • Pluto has five known moons. Its largest moon Charon is more than half the size of Pluto itself, and large enough to orbit a point outside Pluto's surface. In fact, each orbits the common barycenter between them, with Pluto's orbit entirely enclosed by Charon's; thus they form a binary system informally referred to as a double dwarf planet. Pluto's four other moons, Nix, Hydra, Kerberos, and Styx, are far smaller and orbit the Pluto–Charon system.
  • Haumea has two moons with radii estimated around 155 km (Hiʻiaka) and 85 km (Namaka).
  • has one known moon, S/2015 (136472) 1, estimated to be some 100order=flipNaNorder=flip in diameter.
  • 47171 Lempo is a unique trans-Neptunian triple system: Lempo and its moon of roughly equal mass, Hiisi, form a close-proximity binary, separated by roughly 867 km. A second moon, Paha, orbits the Lempo–Hiisi binary at about 7411 km.
  • has one known moon, Dysnomia. Its radius, based on its brightness, is estimated to be roughly between 150 and 350 km.

List

, there are 457 minor planets (systems) with 477 known companions. The following table is a listing of the total number of these systems by orbital class:

of Systems	width=160	Orbital class !		Multiple satellites
align=center	86	Near-Earth objects	align=center		Three systems with two satellites: 3122 Florence,, and .
align=center	31		align=center		One system with two satellites: 2577 Litva.
align=center	212		align=center		Eight systems with two satellites: 45 Eugenia, 87 Sylvia, 93 Minerva, 107 Camilla, 216 Kleopatra, 3749 Balam, 4666 Dietz, 6186 Zenon; and one quadruple system with three satellites: 130 Elektra.
align=center	6	Jupiter trojans	align=center		—
align=center	122	Trans-Neptunian objects	align=center		Two systems with two satellites: 47171 Lempo and 136108 Haumea; one system with five satellites: 134340 Pluto.

Near-Earth objects

This is a list of near-Earth asteroids with companions. Candidate binaries with an unconfirmed status are displayed on a dark background. For an overview, see summary and introduction.

System	Primary	Secondary						width=80 class="unsortable" rowspan=2 style="background-color: #e3e3e3;"	Refs
Designation	Class	De (km)	s/p-ratio	YOD	Dp (km)	RTp (hours)	Designation	YOD	Ds (km)	RTs (hours)	as (km)	Ps (hours)
1862 Apollo	APO	1.55	0.052	1932	1.55	3.065	S/2005 (1862) 1	2005	0.08	–	3.75	27.36
1866 Sisyphus	APO	8.48	0.1	1972	8.44	2.3909	S/1985 (1866) 1	1985	0.84	–	19	27.12
3122 Florence	AMO	4.40	0.04 0.04	1981	4.4	2.3581	S/2017 (3122) 1	2017	0.2	–	4.6	7.2
							S/2017 (3122) 2	2017	0.3	–	9.8	24
3671 Dionysus	AMO	1.46	0.2	1984	1.43	2.705	S/1997 (3671) 1	1997	0.29	–	3.4	27.744
5143 Heracles	APO	3.65	0.167	1991	3.6	2.706	S/2011 (5143) 1	2011	0.6	–	4	15.5
5381 Sekhmet	ATE	1.04	0.3	1991	1	2.7	S/2003 (5381) 1	2003	0.3	10	1.54	12.5
(5646) 1990 TR	AMO	2.72	0.18+	1990	2.68	3.1999	S/2012 (5646) 1	2012	0.48	–	5.1	19.4712
7088 Ishtar	AMO	1.51	0.42	1992	1.39	2.679	S/2006 (7088) 1	2006	0.33	–	2.8	20.6496
(7888) 1993 UC	APO	2.72	–	1993	2.72	2.34	S/2013 (7888) 1	2013	–	–	7.7	35.04
15745 Yuliya	AMO	1.2	0.46+	1991	0.61+	3.2495	S/2018 (15745) 1	2018	0.28+	–	–	11.735
(31345) 1998 PG	AMO	0.94	0.3	1998	0.9	2.51620	S/2001 (31345) 1	2001	0.27	–	1.4	14.0064
	AMO	1.26	0.38+	1998	1.18	2.7358	S/2012 (31346) 1	2021	0.45+	–	4.6	55.39
(35107) 1991 VH	APO	1.12	0.4	1991	1.04	2.624	S/1997 (35107) 1	1997	0.42	–	3.26	32.64
	AMO	1.5	0.41+	1999	1.4	2.7375	S/2015 (53110) 1	2015	0.6+	–	3.8	31.32
65803 Didymos	AMO	0.77	0.22	1996	0.75	2.259	Dimorphos S/2003 (65803) 1	2003	0.17	–	1.18	11.8992
	ATE	0.89	0.48	1998	0.8	2.492	S/2002 (66063) 1	2002	0.38	–	1.2	14.5392
66391 Moshup	ATE	1.39	0.341	1999	1.317	2.7645	Squannit S/2001 (66391) 1	2001	0.451	17.4	2.548	17.4216
	AMO	2.3	–	2000	2.3	2.1102	S/2014 (68063) 1	2014	–	–	3.8	15.7
69230 Hermes	APO	0.81	0.9	1937	0.6	13.894	S/2003 (69230) 1	2003	0.54	13.892	1.1	13.8936
(85275) 1994 LY	AMO	2.51	0.24+	1994	2.44	2.696	S/2020 (85275) 1	2020	0.59+	–	4.2	16.6238
	APO	0.48	0.5	1999	0.43	2.514	S/2004 (85938) 1	2004	0.21	–	0.8	17.7312
	APO	1	0.28	2001	0.96	2.4	S/2001 (88710) 1	2001	0.2	–	1.6	16.399
(136617) 1994 CC	APO	0.64	0.182 0.129	1994	0.62	2.3886	Beta S/2009 (136617) 1	2009	0.113	–	1.729	29.832
							Gamma S/2009 (136617) 2	2009	0.08	–	6.130	201.024
	APO	0.69	0.109	1998	0.69	2.302	S/2012 (136993) 1	2012	0.08	–	–	–
	ATE	3.73	0.23	1999	3.64	2.319	S/1999 (137170) 1	1999	0.84	–	7.3	14.01696
	AMO	2.18	–	2000	2.18	4.243	S/2013 (138095) 1	2013	–	–	–	–
	APO	0.995	0.33	2003	0.94	2.6446	S/2021 (143649) 1	2021	0.31	13.065	1.4	13.07
	ATE	1.65	–	2000	1.65	4.1367	S/2019 (152931) 1	2019	–	16.079	–	–
	AMO	2.85	0.408 0.177	2001	2.6	3.425	Beta S/2008 (153591) 1	2008	1.06	–	16.633	149.4
							Gamma S/2008 (153591) 2	2008	0.46	–	3.804	16.464
	APO	0.46	0.25	2002	0.45	2.817	S/2012 (153958) 1	2012	0.11	–	1.5	26.304
	APO	0.3	0.167	1990	0.3	2.536	S/2003 (162000) 1	2003	0.05	–	0.6	21
	ATE	0.62	0.5	2000	0.55	2.642	S/2005 (162483) 1	2005	0.28	–	1.05	14.16
163693 Atira	ATI	4.9	0.21	2003	4.8	2.9745	S/2017 (163693) 1	2017	1	–	6	15.504
	APO	1.12	0.191	2003	1.1	2.343	S/2004 (164121) 1	2004	0.21	–	3.93	36.696
	APO	1.69	0.28	1996	1.69	3.595195	S/1998 (175706) 1	1998	0.49	16.15	3	16.1508
	APO	0.85	0.41	2000	0.8	2.774	S/2000 (185851) 1	2000	0.3	–	2.62	42.192
	AMO	1.05	–	2005	1.045	40.542	S/2017 (190166) 1	2017	–	–	–	–
	AMO	1.06	–	2006	1.06	182	S/2015 (190208) 1	2015	–	2.62	–	–
	APO	0.28	0.5	2003	0.25	–	S/2017 (226514) 1	2017	0.1	–	–	–
	AMO	0.38	0.18+	2002	0.37	2.5001	S/2018 (250162) 1	2018	0.07+	–	0.5	10.76
	APO	3.46	0.087	2002	3.46	3.2931	S/2004 (276049) 1	2004	0.3	–	4.7	15.6
	AMO	3.09	0.25	1998	3.2	4.751	S/2013 (285263) 1	2013	0.8	1.3046	6.212	31.3104
	AMO	1	–	2000	1	–	S/2021 (285571) 1	2021	–	–	–	–
	APO	0.92	–	2001	0.92	–	S/2017 (310560) 1	2017	–	–	–	–
	APO	0.37	0.2	2004	0.36	2.6	S/2006 (311066) 1	2006	0.07	7	0.75	23.04
	AMO	0.95	0.23	2003	0.93	3.463	S/2021 (326732) 1	2021	0.21	22.92	2	22.92
	AMO	0.6	0.18	2005	0.6	2.4144	S/2015 (348400) 1	2015	0.11	–	0.9	14.736
	APO	0.33	0.21	2004	0.32	2.6	S/2015 (357439) 1	2015	0.07	–	0.5	14.4
	ATE	0.81	0.15	1998	0.8	3-	S/2001 (363027) 1	2001	0.12	<6	4.5	98.4
	APO	0.62	0.065	2000	0.62	5.12	S/2009 (363067) 1	2009	0.04	–	0.61	7.2
	APO	0.17	0.533	2004	0.15	4-	S/2012 (363599) 1	2012	0.08-	–	0.25	20
	APO	1.82	0.28	2006	1.06	2.41	S/2007 (374851) 1	2007	0.3+	–	1.5	5.52
	AMO	1.04	0.49	1994	0.94	2.519	S/1994 (385186) 1	1994	0.46	–	2	22.3296
	AMO	0.55	0.47+	1991	0.5	3.4907	S/2014 (399307) 1	2014	0.24	15.917	0.86	15.91704
	APO	0.54	0.32+	2005	0.5	3.4883	S/2008 (399774) 1	2008	0.2	15.267	0.6	15.2808
	APO	0.17	0.6	2009	0.15	4	S/2015 (410777) 1	2015	0.09	–	0.25	14.4
	APO	0.63	0.333	2008	0.6	2.726	S/2008 (450894) 1	2008	0.2+	–	1.5	28.8
	AMO	1.95	0.24	2005	1.9+	3.339	S/2005 (2005 AB) 1	2005	0.46	–	3.4	17.9304
	APO	0.41	0.2	2006	0.4	2.27	S/2006 (461852) 1	2006	0.08	–	0.5	11.7
	APO	0.53	0.36	2007	0.5	2.603	S/2012 (461852) 1	2012	0.18	–	1.4	33.504
	APO	0.62	0.25	1994	0.6	2.736	S/2005 (488453) 1	2005	0.15+	–	0.6	17.976
	APO	1.067	0.46	2007	0.97	3.497	S/2019 (489486) 1	2019	0.45	41.36	3.2	41.36
	APO	0.29	0.5	2000	0.26	4.44	S/2000 (494658) 1	2000	0.13	–	0.426	18.4
	APO	0.38	–	2008	0.38	–	S/2013 (523625) 1	2013	–	–	–	–
	APO	0.34	0.5-	2014	0.3	–	S/2015 (523775) 1	2015	0.15-	–	–	–
	APO	0.21-	1	1994	0.15-	30	S/2014 (49494) 1	2014	0.15-	–	0.525	30
	APO	0.181	0.45	1999	0.165	3.0697	S/2021 (612098) 1	2021	0.074	-	0.29	16.4448
	AMO	0.61	0.167	2002	0.6	2.7	S/2002 (2002 BM26) 1	2002	0.1	–	1.4	25.8
	AMO	0.51	0.2	2002	0.5	–	S/2002 (2002 KK8) 1	2002	0.1	–	–	–
	APO	0.13	0.5	2003	0.12	–	S/2003 (2003 SS84) 1	2003	0.06	–	0.27	24
	APO	0.40	0.25	2005	0.40	3.6	S/2022 (2003 LW3) 1	2022	0.1	–	4	–
	ATE	0.27	–	2005	0.27	rot.	S/2014 (613286) 1	2014	–	–	–	–
	APO	0.31	0.267	2007	0.3	2.703	S/2007 (2007 DT103) 1	2007	0.08+	–	0.45	13.44
	AMO	0.53	0.24	2013	0.52	3.6246	S/2020 (2013 PY6) 1	2020	0.12	-	1.2	27.312
	APO	1.32	–	2013	1	2.8849	S/2014 (2013 WT44) 1	2014	–	–	–	–
	APO	0.3	0.32+	2014	0.3	3.361	S/2014 (2014 WZ120) 1	2014	0.1	–	0.5	13.665
	APO	0.1	–	2015	0.1	–	S/2015 (2015 TD144) 1	2015	–	–	–	–
	APO	0.47	0.43	2016	0.42	7-	S/2019 (2016 AZ8) 1	2019	0.18-	<40	0.42+	7.2
	APO	0.3	–	2017	0.3	–	S/2017 (2017 RV1) 1	2017	–	–	–	–
	APO	1.3	1	2017	0.9	20.6	S/2018 (2017 YE5) 1	2018	0.9	–	2.4	22.08
	APO	0.24	0.167	2018	0.24	1.2	S/2018 (2018 EB) 1	2018	0.04	–	–	–
	APO	0.28	0.23	2018	0.27	2.4398	S/2018 (2018 TF3) 1	2018	0.06	2.3498	0.35	10.512
	AMO	0.19	–	2020	0.19	–	S/2020 (2020 AZ2) 1	2020	–	–	–	–
	APO	0.18	0.42	2020	0.165	2.8	S/2020 (2020 BX12) 1	2020	0.07	<49	0.36	47.04

Mars crossers

This is a list of Mars-crossing asteroids with companions. Candidate binaries with an unconfirmed status are displayed on a dark background. For an overview, see summary and introduction.

System	Primary	Secondary	width=80 class="unsortable" rowspan=2 style="background-color: #e3e3e3;"	Refs
Designation	Class	De (km)	s/p-ratio	YOD	Dp (km)	RTp (hours)	Designation	YOD	Ds (km)	as (km)	Ps (hours)
1139 Atami	cls.	7.81	0.833	1929	6	27.45	S/2005 (1139) 1	2005	5	15+	27.456
1656 Suomi	H	7.86	0.26+	1942	7.61	2.5885	S/2020 (1656) 1	2020	1.98+	30	57.92
1727 Mette	cls.	10.4	0.21	1965	10.18	2.98109	S/2013 (1727) 1	2013	2.14	21	20.99
2044 Wirt	cls.	6.66	0.25	1950	6.46	3.6898	S/2006 (2044) 1	2006	1.62	12	18.9696
2449 Kenos	cls.	6.2	0.23	1978	6	3.8481	S/2015 (2449) 1	2015	1.4	10	15.84
2577 Litva	cls.	4.4	0.35 0.3	1975	4	2.813	S/2009 (2577) 1	2009	1.4	21	35.88
							S/2012 (2577) 1	2012	1.2	378	5136
3873 Roddy	cls.	7.51	0.27	1984	7.25	2.47900	S/2012 (3873) 1	2012	1.96	14	19.24
4435 Holt	cls.	5.03	0.34+	1983	4.76	2.867	S/2017 (4435) 1	2017	1.62+	16	42.648
5261 Eureka	cls.	1.28	0.39+	1990	1.19	2.6902	S/2011 (5261) 1	2011	0.46	2.1	16.9296
(5407) 1992 AX	cls.	3.98	0.2	1992	3.9	2.549	S/1997 (5407) 1	1997	0.78	5.8	13.5192
7002 Bronshten	cls.	3.12	0.24+	1971	3.03	2.67025	S/2018 (7002) 1	2018	0.73+	4.5	13.32
7369 Gavrilin	cls.	7.92	0.32+	1975	7.54	49.12	S/2007 (7369) 1	2007	2.41	27	49.128
8373 Stephengould	unus.	5.48	0.27-	1992	5.29	4.435	S/2010 (8373) 1	2010	1.43	15	34.152
12008 Kandrup	cls.	4.2	0.75	1996	3.4	32.9034	S/2016 (12008) 1	2016	2.6	10	32.904
13920 Montecorvino	cls.	2.81	0.22+	1985	2.81	2.20231	S/2020 (13920) 1	2020	-	-	15.475
(15700) 1987 QD	cls.	4.15	0.31	1987	3.96	3.0586	S/2010 (15700) 1	2010	1.23	14	50.4
(16635) 1993 QO	cls.	4.77	0.27+	1993	4.61	7.622	S/2007 (16635) 1	2007	1.24	12	32.256
(23621) 1996 PA	cls.	2.5	0.27+	1996	2.4	2.6649	S/2017 (23621) 1	2017	0.65	5	20.60
24495 Degroff	cls.	3.5	–	2001	3.26	24.083	S/2017 (24495) 1	2017	–	–	2.7375
26074 Carlwirtz	cls.	3.62	–	1977	3.62	2.4593	S/2013 (26074) 1	2013	–	6.1	16.1112
26471 Tracybecker	cls.	6.05	0.36	2000	5.69	2.687	S/2009 (26471) 1	2009	2.05	18	39.288
	cls.	4.15	0.32+	2000	3.96	6.5979	S/2007 (32039) 1	2007	1.27	53	360
	cls.	3.62	0.28	2001	3.48	2.5644	S/2005 (34706) 1	2005	0.98	7	20.76
	cls.	3.3	0.21+	2000	3.23	2.5572	S/2012 (51356) 1	2012	0.68	13	62.04
	cls.	2.62	0.23+	1999	2.55	3.330	S/2013 (53432) 1	2013	0.59	4	14.1
	cls.	3.3	0.19+	2001	3.2	2.7077	S/2016 (54697) 1	2016	0.6	–	16.2648
	cls.	6.89	0.19	1997	6.77	2.83507	S/2010 (99913)	2010	1.29	11	14.6808
	cls.	2.4	0.35	1989	2.3	2.4172	S/2018 (100015) 1	2018	0.8	4.5	20.65
	cls.	2.62	–	2002	2.19	2.9649	S/2005 (114319) 1	2005	–	–	7.954
	cls.	2.97	–	2002	–	587	S/2010 (218144) 1	2010	–	–	–

Main-belt asteroids

This is a list of main-belt asteroids with companions. Candidate binaries with an unconfirmed status are displayed on a dark background. For an overview, see summary and introduction.

System	Primary	Secondary	width=85 class="unsortable" rowspan=2 style="background-color: #e3e3e3;"	Refs
Designation	Class	De (km)	s/p-ratio	YOD	Dp (km)	RTp (hours)	Designation	YOD	Ds (km)	as (km)	Ps (hours)
22 Kalliope	—	168.5	0.168	1852	166.2	4.1482	Linus S/2001 (22) 1	2001	28	1095	86.304
31 Euphrosyne	EUP	267.08	0.025	1854	267.08	5.53	S/2019 (31) 1	2019	6.7	677	28.8
41 Daphne	—	174	0.011	1856	174	5.9880	Peneius S/2008 (41) 1	2008	2-	443	26.4
45 Eugenia	—	206	0.034 0.024	1857	206	5.699	Petit-Prince S/1998 (45) 1	1998	7	1164	113.18
								2004	5	611	43.03
87 Sylvia	SYL	286	0.038 0.037	1866	286	5.1836	Romulus S/2001 (87)	2001	10.8	1351	87.696
							Remus S/2004 (87)	2004	10.6	701.6	32.952
90 Antiope	THM	121	0.954	1866	87.8	16.505	S/2000 (90) 1	2000	87.8	171	16.505
93 Minerva	GEF	141.6	0.028 0.021	1867	141.6	5.9818	Aegis S/2009 (93) 1	2009	3.6	623.5	57.744
							Gorgoneion S/2009 (93) 2	2009	3.2	375	26.7528
107 Camilla	SYL	219.37	0.073 0.016	1868	219.37	4.8439	S/2001 (107) 1	2001	16	1250	89.328
							S/2016 (107) 1	2016	3.5	340	12
113 Amalthea	FLO	50.1	–	1871	50.1	9.95	S/2017 (113) 1	2017	5	–	–
121 Hermione	7:4	190	0.171	1872	187	5.551	S/2002 (121) 1	2002	32	747	61.512
130 Elektra	—	199	0.03 0.01 0.008	1873	199	5.2247	S/2003 (130) 1	2003	6.0	1298	126.9
							S/2014 (130) 1	2014	2.0	498	30.14
							S/2014 (130) 2	2014	1.6	345	16.8
216 Kleopatra	—	135	0.066 0.051	1880	135	5.38528	Alexhelios S/2008 (216) 1	2008	8.9	678	55.68
							Cleoselene S/2008 (216) 2	2008	6.9	454	29.76
243 Ida	KOR	31.4	0.045	1884	31.4	4.6336	Dactyl (Ida I)	1993	1.4	108	36.96
283 Emma	EMA	134.7	0.067	1889	134.7	6.888	S/2003 (283) 1	2003	9	581	80.472
317 Roxane	—	20.56	0.267	1891	19.86	8.169	Olympias S/2009 (317) 1	2009	5.3	257	336
379 Huenna	THM	87.47	0.066	1894	87.47	7.022	S/2003 (379) 1	2003	5.8	3336	2102
702 Alauda	ALA	201.96	0.017	1910	201.96	8.354	Pichi üñëm S/2007 (702) 1	2007	3.51	1227	117.9
762 Pulcova	—	143	0.134	1913	141.72	5.839	S/2000 (762) 1	2000	19	703	106.51
809 Lundia	FLO	9.1	0.89	1915	6.9	15.418	S/2005 (809) 1	2005	6.1	15.8	15.418
854 Frostia	—	7.84	0.724	1916	6.35	37.728	S/2004 (854) 1	2004	4.6	17	37.73
939 Isberga	—	12.9	0.29	1920	12.4	2.9170	S/2006 (939) 1	2006	3.6	33	26.630
1016 Anitra	FLO	9.54	–	1924	9.54	5.9295	S/2016 (1016) 1	2016	–	–	–
1052 Belgica	FLO	10.41	0.36+	1925	9.79	2.7097	S/2012 (1052) 1	2012	3.53	34	47.26
1089 Tama	—	12.92	0.685	1927	10.7	16.444	S/2003 (1089) 1	2003	7.33	20.7	16.445
1313 Berna	—	13.5	0.79	1933	10.6	25.464	S/2004 (1313) 1	2004	8.37	25	25.464
1333 Cevenola	EUN	17.15	0.35	1934	17.15	4.88	S/2008 (1333) 1	2008	–	–	–
1338 Duponta	FLO	7.88	0.23	1934	7.68	3.8545	S/2007 (1338) 1	2007	1.77	14	17.57
1344 Caubeta	—	5.84	–	1935	5.84	3.122	S/2011 (1344) 1	2011	–	–	–
1453 Fennia	H	7.23	0.28+	1938	6.96	4.4121	S/2007 (1453) 1	2007	1.95	15	22.9896
1509 Esclangona	H	8.17	0.331	1938	7.76	3.253	S/2003 (1509) 1	2003	2.57	140	552
1526 Mikkeli	—	5.32	0.2	1939	5.22	2.9341	S/2020 (1526) 1	2020	1.04	8.8	15.9792
1626 Sadeya	—	15.14	0.26	1927	14.65	3.4202	S/2020 (1626) 1	2020	3.81	54	51.312
1717 Arlon	—	9.13	–	1954	9.13	5.148	S/2005 (1717) 1	2005	–	17	18.235
1770 Schlesinger	—	10.61	–	1967	10.61	2.8804	S/2016 (1770) 1	2016	–	–	–
1798 Watts	FLO	6.63	–	1949	6.63	–	S/2017 (1798) 1	2017	–	–	–
1803 Zwicky	PHO	9.93	0.26	1967	9.61	2.7329	S/2021 (1803) 1	2021	2.50	24	28.459
1830 Pogson	FLO	8.28	0.32+	1968	7.89	2.57	S/2007 (1830) 1	2007	2.52	18	24.24
1934 Jeffers	PHO	9.24	–	1972	9.24	6.0427	S/2020 (1934) 1	2020	–	15	15.014
2006 Polonskaya	FLO	4.62	0.22+	1973	4.51	3.118	S/2005 (2006) 1	2005	0.99	8.5	19.1496
2019 van Albada	FLO	7.86	0.26+	1935	7.61	2.7294	S/2019 (2019) 1	2019	1.98+	14	17.982
2047 Smetana	H	3.07	0.21+	1971	3	2.497	S/2012 (2047) 1	2012	0.63	6.3	22.4304
2070 Humason	—	4.57	0.31	1964	4.37	3.1883	S/2018 (2070) 1	2018	1.35	17	53.50
2121 Sevastopol	FLO	9.32	0.41	1971	8.62	2.9064	S/2010 (2121) 1	2010	3.54	26	37.104
2131 Mayall	H	8.56	0.26+	1975	8.28	2.568	S/2009 (2131) 1	2009	2.15	18	23.4792
2178 Kazakhstania	—	4.31	0.26	1972	4.17	3.0183	S/2018 (2178) 1	2018	1.08	8	18.50
2242 Balaton	—	6.13	0.25+	1936	5.95	2.7979	S/2015 (2242) 1	2015	1.49+	9	12.96
2337 Boubín	—	8.01	0.16+	1976	7.91	2.53163	S/2018 (2337) 1	2018	1.27+	13	16.09
2343 Siding Spring	NYS	5.2	0.19+	1979	5.11	2.10637	S/2015 (2343) 1	2015	0.97+	7	11.78904
2478 Tokai	FLO	9.98	0.72+	1981	8.1	25.885	S/2007 (2478) 1	2007	5.83	21	25.896
2486 Metsähovi	—	8.42	–	1939	8.42	4.4518	S/2007 (2486) 1	2007	–	–	–
2491 Tvashtri	H	3.259	0.24+	1977	3.17	4.0852	S/2018 (2491) 1	2018	0.76+	7.5	26.71
2516 Roman	—	4.408	0.23	1964	4.3	2.6266	S/2019 (2516) 1	2019	0.99	7.3	16.2192
2535 Hämeenlinna	—	9.42	0.22+	1939	9.2	3.23106	S/2015 (2535) 1	2015	2.0+	19	21.2304
2602 Moore	—	9.6	0.28	1982	9.2	3.46723	S/2019 (2602) 1	2019	2.6	22	27.455
2623 Zech	—	7.92	0.29+	1919	7.61	2.7401	S/2014 (2623) 1	2014	2.21+	48	117.19
2691 Sersic	—	5.44	0.43+	1974	5	3.8811	S/2011 (2691) 1	2011	2.15	12	26.808
2754 Efimov	—	6.58	0.2	1966	6.46	2.4497	S/2006 (2754) 1	2006	1.29	10	14.7648
2815 Soma	FLO	7.16	0.25	1982	6.95	2.73325	S/2011 (2815) 1	2011	1.74	13	17.916
2825 Crosby	—	5.06	0.18+	1938	4.98	2.8135	S/2017 (2825) 1	2017	0.9+	–	14.3496
2873 Binzel	FLO	6.43	0.25+	1982	6.24	2.7037	S/2019 (2873) 1	2019	1.56+	n.a.	44.58
2881 Meiden	—	5.67	–	1983	5.67	3.48	S/2017 (2881) 1	2017	–	–	–
3034 Climenhaga	—	9.97	–	1917	9.97	2.73749	S/2009 (3034) 1	2009	–	19	18.9552
3073 Kursk	FLO	6.89	0.25	1979	6.69	3.4468	S/2006 (3073) 1	2006	1.67	22	44.952
3169 Ostro	H	5.15	0.87	1981	3.89	6.509	S/2005 (3169) 1	2005	3.38	5.2	6.5088
3309 Brorfelde	H	5.04	0.26	1982	4.88	2.5041	S/2005 (3309) 1	2005	1.27	9	18.48
3378 Susanvictoria	—	6.64	0.24+	1922	6.46	2.5621	S/2017 (3378) 1	2017	1.55+	11	17.1312
3390 Demanet	FLO	5.06	0.26	1984	4.9	2.59457	S/2021 (3390) 1	2021	1.27	14	37.14
3433 Fehrenbach	—	7.74	0.31	1963	7.4	3.916	S/2015 (3433) 1	2015	2.3	14	19.6656
3523 Arina	—	9.07	0.24+	1975	8.82	2.6742	S/2021 (3523) 1	2021	2.12+	22	29.261
3623 Chaplin	KOR	11.1	–	1981	11.1	8.361	S/2008 (3623) 1	2008	–	–	–
3673 Levy	—	6.41	0.28	1985	6.17	2.688	S/2007 (3673) 1	2007	1.73	13	21.6
3703 Volkonskaya	V	3.73	0.4	1978	3.46	3.235	S/2005 (3703) 1	2005	1.39	7.8	24
3749 Balam	FLO	4.66	0.466 0.42	1982	3.95	2.80483	S/2002 (3749) 1	2002	1.84	289	1464
							S/2008 (3749) 1	2008	1.66	20	33.384
3782 Celle	V	5.92	0.43	1986	5.44	3.839	S/2003 (3782) 1	2003	2.34	18	36.576
3792 Preston	PHO	5.16	–	1985	5.16	2.9277	S/2016 (3792) 1	2016	–	–	46.8
3657 Ermolova	V	6.66	0.14	1978	6.6	2.60655	S/2020 (3657) 1	2020	0.92	9.4	12.540
3841 Dicicco	FLO	6.25	0.28+	1983	6.02	3.5949	S/2014 (3841) 1	2014	1.67+	12	21.6288
3865 Lindbloom	V	7.97	0.65+	1988	6.68-	26.016	S/2020 (3865) 1	2020	4.34+	17	26.016
3868 Mendoza	—	9.35	0.22	1960	9.13	2.7709	S/2009 (3868) 1	2009	2.01	20	24.384
3905 Doppler	—	7.91	0.77+	1984	6.27	50.8	S/2013 (3905) 1	2013	4.83	26	50.808
3912 Troja	—	5.93	0.33	1988	5.63	3.6594	S/2021 (3912) 1	2021	1.86	10	17.371
3951 Zichichi	—	6.72	0.33+	1986	6.38	3.3942	S/2006 (3951) 1	2006	2.11	16	27.6
3982 Kastelʹ	—	6.79	–	1984	6.79	5.835	S/2005 (3982) 1	2005	–	–	–
4029 Bridges	—	8.02	0.24	1982	7.8	3.5746	S/2006 (4029) 1	2006	1.87	13	16.3104
4030 Archenhold	—	6.97	0.31+	1984	6.66	3.27292	S/2020 (4030) 1	2020	2.06+	12	15.9739
4092 Tyr	—	7.6	0.45+	1986	7.6	16.0875	S/2020 (4092) 1	2020	–	14	16.0875
4272 Entsuji	—	7.68	0.18	1977	7.56	2.8087	S/2015 (4272) 1	2015	1.36	13	15.9456
4288 Tokyotech	EUN	12.3	0.30+	1989	11.78	3.18	S/2019 (4288) 1	2019	3.53+	30	30.276
4296 van Woerkom	FLO	7.6	0.3	1935	7.3	2.809	S/2016 (4296) 1	2016	2.2	17	26.232
4337 Arecibo	THM	19.69	0.53	1985	24.3	–	S/2021 (4337) 1	2021	13	48	19.2
4362 Carlisle	FLO	5.59	0.33+	1978	5.31-	2.63289	S/2021 (4362) 1	2021	1.75+	17	43.296
4383 Suruga	—	6.47	0.21+	1989	6.33	3.4068	S/2013 (4383) 1	2013	1.33	11	16.3872
4440 Tchantchès	H	2.09	0.25+	1984	2.03	2.78836	S/2005 (4440) 1	2005	0.51	3.8	18.6912
4492 Debussy	—	17.36	0.643	1988	14.6	26.606	S/2004 (4492) 1	2004	9.39	31	26.616
4514 Vilen	—	6.29	0.26	1972	6.09	2.8922	S/2015 (4514) 1	2015	1.58+	11	16.8504
4541 Mizuno	—	6.29	–	1989	6.29	5.261	S/2015 (4541) 1	2015	–	–	–
4607 Seilandfarm	—	7.39	0.29+	1987	7.1	3.9683	S/2009 (4607) 1	2009	2.06	19	31.632
4666 Dietz	—	6.83	0.34 –	1986	6.52	2.95242	S/2015 (4666) 1	2015	2.22+	18	33.192
							S/2015 (4666) 2	2015	–	–	–
4674 Pauling	H	4.68	0.32	1989	4.46	2.521	S/2004 (4674) 1	2004	1.41	250	3120
4765 Wasserburg	H	1.78	0.16+	1986	1.76	3.6231	S/2013 (4675) 1	2013	0.28	2.9	15.9696
4786 Tatianina	—	3.28	0.19+	1985	3.22	2.9227	S/2006 (4786) 1	2006	0.61	6.6	21.6696
4788 Simpson	—	3.58	0.17+	1986	3.53	2.81752	S/2020 (4788) 1	2020	0.6+	5.7	14.981
4868 Knushevia	H	1.535	0.13+	1989	1.52	3.1422	S/2015 (4868) 1	2015	0.2+	2.1	11.922
4951 Iwamoto	—	5.52	0.76+	1990	4.39	118.0	S/2007 (4951) 1	2007	3.34	31	118.0
5112 Kusaji	FLO	3.42	0.31	1987	3.27	2.7995	S/2016 (5112) 1	2016	1.01	7	20.74
5135 Nibutani	—	4.82	0.28	1990	4.64	2.818	S/2020 (5135) 1	2020	1.3	9.6	21.7368
5402 Kejosmith	—	4.19	0.18+	1989	4.12	2.69549	S/2018 (5402) 1	2018	–	12	36.62
5425 Vojtěch	V	7.05	0.22	1984	6.89	2.64759	S/2015 (5425) 1	2015	1.52	16	25.4304
5426 Sharp	H	2.033	–	1985	2.033	4.5609	S/2014 (5426) 1	2014	–	4.5	24.2208
5474 Gingasen	V	5.05	–	1988	5.05	3.6242	S/2008 (5474) 1	2008	–	–	–
5477 Holmes	H	3.15	0.37	1989	2.95	2.9943	S/2005 (5477) 1	2005	1.09	6.7	24.43
5481 Kiuchi	V	7.92	0.33	1990	7.52	3.6196	S/2008 (5481) 1	2008	2.48	15	20.90
5500 Twilley	FLO	4.48	0.27+	1981	4.33	2.9554	S/2017 (5500) 1	2017	1.17+	7.8	17.556
5536 Honeycutt	—	9.1	0.31	1955	8.7	3.583	S/2016 (5536) 1	2016	2.7	15	16.325
5674 Wolff	—	6.04	0.8+	1986	4.72	93.7	S/2015 (5674) 1	2015	3.78+	30	93.696
5772 Johnlambert	—	8	0.22+	1988	7.81	3.0782	S/2021 (5772) 1	2021	1.72+	14	17.98
5872 Sugano	—	6.33	0.3+	1989	6.06	3.3642	S/2016 (5872) 1	2016	1.82+	11	18.84
5899 Jedicke	H	2.67	0.32+	1986	2.54	2.748	S/2010 (5899) 1	2010	0.81	4.4	16.699
5905 Johnson	H	4.79	0.40	1989	4.45	3.7824	S/2005 (5905) 1	2005	1.78	9.3	21.785
6009 Yuzuruyoshii	—	10.32	0.29+	1990	9.91	3.03067	S/2021 (6009) 1	2021	2.87+	33	44.07
6016 Carnelli	—	3.53	0.2	1991	3.46	2.8028	S/2016 (6016) 1	2016	0.69	7	21.331
6084 Bascom	—	6.35	0.37	1985	5.96	2.745	S/2006 (6084) 1	2006	2.2	20	43.512
6100 Kunitomoikkansai	—	4.06	0.38+	1991	3.8	4.3018	S/2016 (6100) 1	2016	1.44+	7	18.46
6181 Bobweber	—	4.49	–	1986	4.49	2.75796	S/2008 (6181) 1	2008	–	–	–
6186 Zenon	—	6	0.28	1988	5.8	2.6832	S/2017 (6186) 1	2017	1.6	9.1	14.393
6244 Okamoto	—	6.89	0.25	1990	6.69	2.8958	S/2006 (6244) 1	2006	1.67	13	20.3208
6245 Ikufumi	—	8.1	0.23	1990	7.89	2.9222	S/2018 (6245) 1	2018	1.89	13	15.44
	—	4.95	0.24	1985	4.81	2.709	S/2007 (6265) 1	2007	1.16	8	15.8592
(6369) 1983 UC	FLO	5.17	0.35	1983	4.9	2.9	S/2013 (6369) 1	2013	1.7	15–	39.8
6384 Kervin	H	3.74	0.3+	1989	3.6	3.6194	S/2015 (6384) 1	2015	1.1+	6.1	15.94
6615 Plutarchos	—	3.14	0.25	1960	3.05	2.3247	S/2007 (6615) 1	2007	0.76	9.7	40.03
6708 Bobbievaile	—	9.23	0.57+	1989	8.02	8.221	S/2009 (6708) 1	2009	4.57	19	24.696
7187 Isobe	H	6.05	0.17	1992	5.96	4.2427	S/2012 (7187) 1	2012	1.01	16	33.1
7225 Huntress	—	6.68	0.21	1983	6.54	2.4400	S/2007 (7225) 1	2007	1.37	10	14.6712
7307 Takei	—	10.1	0.24+	1994	9.8	2.74685	S/2021 (7307) 1	2021	2.6	19	20.0064
7344 Summerfield	—	6.25	–	1992	6.25	–	S/2017 (7344) 1	2017	–	–	–
7393 Luginbuhl	FLO	5.47	0.4+	1984	5.08	2.68763	S/2019 (7393) 1	2017	2.03+	16	39.4224
	—	7.45	–	1995	7.45	3.16001	S/2021 (7792)	2021	–	–	–
7958 Leakey	H	2.94	0.30	1994	2.82	2.34843	S/2012 (7958) 1	2012	0.85	10	50.28
8026 Johnmckay	H	1.69	–	1991	1.69	372	S/2010 (8026) 1	2010	–	–	–
8077 Hoyle	—	12	s/p	1986	12	2.7454	S/2000 (8077) 1	2000	–	–	–
8116 Jeanperrin	FLO	4.77	0.33+	1996	4.53	3.6169	S/2007 (8116) 1	2007	1.49	13	36.144
8306 Shoko	FLO	3.46	0.40+	1995	3.21	3.350	S/2013 (8306) 1	2013	1.28	9.4	36.192
8474 Rettig	FLO	6	0.86+	1985	4.5	30.54	S/2015 (8474) 1	2015	3.9+	14	30.54
9069 Hovland	H	3.13	0.30+	1993	3	4.2175	S/2004 (9069) 1	2004	0.9	7.8	30.336
9260 Edwardolson	—	4.12	0.27	1953	3.98	3.0852	S/2005 (9260) 1	2005	1.07	7.2	17.784
	EUN	6.18	0.26	1990	5.98	2.98701	S/2019 (9332) 1	2019	1.55	21	48.84
9617 Grahamchapman	FLO	2.84	0.27	1993	2.74	2.2856	S/2006 (9617) 1	2006	0.74	5.2	19.3848
9783 Tensho-kan	—	5.33	0.35	1994	5.1	2.9	S/2013 (9783) 1	2013	1.8	13–	29.568
9972 Minoruoda	—	9.1	–	1993	–	–	S/2017 (9972) 1	2017	–	–	–
10123 Fideöja	—	3.48	0.35	1993	3.3	2.87	S/2013 (10123) 1	2013	1.2	13–	56.448
10132 Lummelunda	—	3.589	0.28+	1993	3.46	2.5099	S/2017 (10132) 1	2017	0.97+	7.3	22.44
10208 Germanicus	FLO	3.55	0.46	1997	3.23	3.34825	S/2007 (10208) 1	2007	1.48	13	58.56
	H	3.3	–	1999	3.3	4.8219	S/2013 (11217) 1	2013	–	6.2	19.1712
11227 Ksenborisova	—	2.6	–	1999	2.6	2.61679	S/2017 (11227) 1	2017	–	–	–
11264 Claudiomaccone	—	4.2	0.31+	1979	4-	3.1872	S/2005 (11264) 1	2005	1.24+	6	15.1104
12326 Shirasaki	FLO	3.8	0.24	1992	3.7	2.7286	S/2016 (12326) 1	2016	0.9	8.4	25.056
13123 Tyson	PHO	10.87	–	1994	10.87	3.3303	S/2015 (13123) 1	2015	–	–	–
15107 Toepperwein	FLO	2.86	0.19+	2000	2.81	2.5327	S/2021 (15107) 1	2021	0.53+	5.4	19.6032
15268 Wendelinefroger	NYS	3.97	0.27+	1990	3.83	2.4224	S/2008 (15268) 1	2008	1.03	8.7	25.08
	—	3.74	–	1998	3.74	2.5273	S/2010 (15430) 1	2010	–	8.2	23.9592
15822 Genefahnestock	H	1.72	0.19+	1994	1.69	2.96	S/2010 (15822) 1	2010	0.32	3.3	20.1312
16525 Shumarinaiko	NYS	5.25	0.16+	1991	5.18	2.5932	S/2013 (16525) 1	2013	0.83	8.1	14.4096
(16694) 1995 AJ	FLO	4.06	0.23+	1995	3.96	3.6421	S/2020 (16694) 1	2020	0.91+	9	25.2792
17081 Jaytee	—	4.52	0.26+	1999	4.37	2.8818	S/2021 (17081) 1	2021	1.137+	7.5	16.34
17246 Christophedumas	KOR	4.61	0.222	2000	4.5	5+	S/2004 (17246) 1	2004	1	228	2160
17260 Kušnirák	—	4.77	0.26	2000	4.62	3.1287	S/2006 (17260) 1	2006	1.2	7.4	14.7576
17700 Oleksiygolubov	—	3.45	0.31+	1997	3.29	3.8382	S/2018 (17700) 1	2018	1.02+	5.4	15.49
(18303) 1980 PU	—	4.38	0.24	1980	4.3	2.72627	S/2019 (18303) 1	2019	1	6.1	12.27
	PHO	3.529	0.24+	1996	3.43	3.4391	S/2021 (18503) 1	2021	0.82+	6.7	19.904
	V	3.35	0.32	1996	3.19	3.3529	S/2018 (18527) 1	2018	1.02	6	19.07
	H	4	0.27+	2000	3.86	3.8216	S/2014 (18890) 1	2014	1.04+	6	14.2896
20325 Julianoey	—	4.94	0.3	1998	4.73	3.24474	S/2014 (20325) 1	2014	1.42	10	23.5
20882 Paulsánchez	NYS	4.4	–	2000	4.4	2.5586	S/2018 (20882) 1	2018	–	12	32.810
21436 Chaoyichi	—	1.95	s/p	1998	1.8	2.87	S/2014 (21436) 1	2014	0.6	0.35	–
21527 Horton	EUN	4.99	0.21+	1998	4.88	2.76762	S/2019 (21527) 1	2019	1.02+	8.7	17.44
22899 Alconrad	KOR	5.68	0.222	1999	5.54	4.03	S/2003 (22899) 1	2003	1.23	182	1344
	—	–	–	1999	–	–	S/2020 (24106) 1	2020	–	–	–
	H	3.18	0.22+	2000	3.1	2.66087	S/2016 (24465) 1	2016	0.68	3.6	9.252
25015 Lairdclose	FLO	2.899	–	1998	2.9	–	S/2016 (25015) 1	2018	–	–	–
25021 Nischaykumar	—	2.1	0.28	1998	2	2.5344	S/2019 (25021) 1	2019	0.56	n.a.	23.496
	—	4.56	–	1999	4.56	2.907	S/2015 (26416) 1	2015	–	–	–
	—	2.02	0.34+	1999	1.91	3.2	S/2019 (26420) 1	2019	0.65+	n.a.	23.899
	H	1.82	s/p	2000	1.82	3.4885	S/2013 (26578) 1	2013	–	3.1	16.356
27675 Paulmaley	PHO	5.09	–	1981	5.09	–	S/2017 (27675) 1	2017	–	–	–
31450 Stevepreston	—	10.62	0.22	1999	10.4	3.4116	S/2015 (31450) 1	2015	2.3	39	53.47
32008 Adriángalád	—	4.56	0.4+	2000	4.23	3.0171	S/2007 (32008) 1	2007	1.69	13	40.25
	PHO	3.4	–	1999	3.4	16.675	S/2020 (38079) 1	2020	–	–	–
	—	2.5	0.35	1999	2.4	2.9	S/2014 (43008) 1	2014	0.8	–	–
	—	2.62	0.35	1999	0.66	2.9	S/2014 (44620) 1	2014	0.2	2	–
46829 McMahon	—	3.3	0.4	1998	3.06	2.6236	S/2015 (46829) 1	2015	1.22	5.4	16.833
52316 Daveslater	H	3.3	0.16+	1992	3.26	2.7629	S/2012 (52316) 1	2012	0.52	4.9	13.44
	—	2.2	0.25+	2001	2.2	2.44482	S/2017 (57202) 1	2017	0.5+	5	24
69406 Martz-Kohl	H	3.18	0.19+	1995	3.12	4.486	S/2013 (69406) 1	2013	0.59	5.3	16.11
	PHO	2.7	0.25+	2000	2.62	2.582	S/2019 (72036) 1	2019	0.66+	4.9	18.77
76818 Brianenke	H	3.84	0.37	2000	3.6	3.166	S/2005 (76818) 1	2005	1.33	5.6	14.12
79472 Chiorny	H	3.79	0.32	1998	3.79	2.8802	S/2012 (79472) 1	2012	–	9	25.94
	—	1.58	0.3	1999	0.28	2.9	S/2012 (80218) 1	2012	0.08	0.9	33.1
152830 Dinkinesh	FLO	0.82	0.28	1999	0.76	52.67 ± 0.04	Selam S/2023 (152830) 1	2023	0.22	?	?
	—	2.6	1	2006	1.8	–	S/2011 (300163) 1	2011	1.8	104	3360

The following binaries are double asteroids, with similarly sized components, and a barycenter outside of the larger object.

1. 90 Antiope — S/2000 (90) 1
2. 854 Frostia — S/2004 (854) 1
3. 1313 Berna — S/2004 (1313) 1
4. 2478 Tokai — S/2007 (2478) 1
5. 3169 Ostro — S/2005 (3169) 1
6. 3749 Balam — S/2002 (3749) 1
7. 3905 Doppler — S/2013 (3905) 1
8. 4674 Pauling — S/2004 (4674) 1
9. 4951 Iwamoto — S/2007 (4951) 1
10. 5674 Wolff — S/2015 (5674) 1
11. 8474 Rettig — S/2015 (8474) 1
12. 17246 Christophedumas — S/2004 (17246) 1
13. — S/2011 (300163) 1

In addition, these bodies might be double asteroids, but due to errors in their size and orbit, it is uncertain.

1. 809 Lundia — S/2005 (809) 1
2. 1089 Tama — S/2003 (1089) 1
3. 1509 Esclangona — S/2003 (1509) 1
4. 4492 Debussy — S/2004 (4492) 1
5. 11264 Claudiomaccone — S/2003 (11264) 1
6. 22899 Alconrad — S/2003 (22899) 1

Jupiter trojans

This is a list of Jupiter trojans with companions. Candidate binaries with an unconfirmed status are displayed on a dark background. For an overview, see summary and introduction.

System	Primary	Secondary	width=95 class="unsortable" rowspan=2 style="background-color: #e3e3e3;"	Refs
Designation	Class	De (km)	s/p-ratio	YOD	Dp (km)	RTp (hours)	Designation	YOD	Ds (km)	as (km)	Ps (hours)
617 Patroclus	L5	145	0.924	1906	106	102.79	Menoetius	2001	98	680	102.792
624 Hektor	L4	250	0.048	1907	184	6.921	Skamandrios	2006	12	957.5	71.162
3548 Eurybates	L4	63.9	0.013	1973	63.9	8.711	Queta	2018	0.8	2310	1982.4
16974 Iphthime	L4	57.3	0.767	1998	45.5	78.9	S/2013 (16974) 1	2013	34.9	179	78.96
17365 Thymbraeus	L5	42.6	0.843	1978	32.6	12.672	S/2005 (17365) 1	2005	27.5	43	12.672
29314 Eurydamas	L5	40	0.737	1994	32	15.035	S/2005 (29314) 1	2005	24	41	15.036
15094 Polymele	L4			1999	21		Shaun (temporary designation)^[1]	2022

Trans-Neptunian objects

This is a list of trans-Neptunian objects with companions. Candidate binaries with an unconfirmed status are displayed on a dark background. This list gives the companion's orbital period (P_s) in days rather than hours. For an overview, see summary and introduction.

System	Primary	Secondary	width=85 class="unsortable" rowspan=2 style="background-color: #e3e3e3;"	Refs
Designation	Class	De (km)	s/p-ratio	YOD	Dp (km)	RTp (hours)	Designation	YOD	Ds (km)	as (km)	Ps (days)
	1:2	280	0.302	1998	268	8.4	S/2001 (26308) 1	2001	81	11377	130.158
38628 Huya	PLU	458	0.525	2000	406	5.28	S/2012 (38628) 1	2012	213	1740	3.2
42355 Typhon	SDO	185	0.55	2002	162	9.67	Echidna (Typhon I)	2006	89	1580	18.982
47171 Lempo	PLU	393	0.486 0.927	1999	272	45.763	Paha (Lempo I)	2001	132	7411	50.3
							Hiisi (Lempo II)	2007	251	867	1.907
	SDO	194	0.457	1995	176	–	S/2002 (48639) 1	2002	80	420	1.4
50000 Quaoar	CUB	1074	0.076	2002	1070	8.839	Weywot (Quaoar I)	2006	81	13800	12.26
	CUB	697	0.316	2002	665	14.382	S/2007 (55637) 1	2007	210	4770	8.309
58534 Logos	CUB	106	0.766	1997	82	–	Zoe (Logos I)	2001	67	8217	309.87
	SDO	211	0.769	2000	167	–	S/2006 (60458) 1	2006	128	2200	15
	2:5	183	0.759	2000	146	–	S/2007 (60621) 1	2007	111	1180	7.5
65489 Ceto	SDO	281	0.764	2003	223	4.43	Phorcys (Ceto I)	2006	171	1840	9.554
66652 Borasisi	CUB	163	0.817	1999	126	6.4	Pabu (Borasisi I)	2003	103	4528	46.2888
79360 Sila–Nunam	CUB	343	0.944	1997	249	300.2388	Nunam	2002	236	2777	12.51
	CUB	201	0.759	2000	160	–	S/2005 (80806) 1	2002	121	2700	23
	3:8	229	0.347	2000	216	–	S/2005 (82075) 1	2002	75	1900	10
	CUB	183	0.867	2001	138	–	S/2008 (82157) 1	2008	120	3130	33
88611 Teharonhiawako	CUB	220	0.724	2001	178	9.505	Sawiskera (Teharonhiawako I)	2001	129	27670	828.76
90482 Orcus	PLU	958	0.31	2004	917	13.18841	Vanth (Orcus I)	2005	442	9006	9.539
	CUB	211	0.955	2001	153	–	S/2007 (119067) 1	2007	146	8900	130
	1:2	461	0.316	2002	440	–	S/2007 (119979) 1	2006	139	4090	8.403
120347 Salacia	CUB	901	0.344	2004	854	6.5	Actaea (Salacia I)	2006	286	5619	5.4938
	CUB	146	0.951	2000	106	–	S/2007 (123509) 1	2005	101	2366	30.917
134340 Pluto	PLU	2376	0.511 0.018 0.016 0.012 0.0025	1930	2380	153.2935	Charon (Pluto I)	1978	1212	19573	6.3872
							Nix (Pluto II)	2005	38	48694	24.8546
							Hydra (Pluto III)	2005	39	64738	38.2018
							Kerberos (Pluto IV)	2011	13	57783	32.1676
							Styx (Pluto V)	2012	11	42656	20.1616
	CUB	175	0.783	2000	138	–	S/2003 (134860) 1	2003	108	2270	22.0584
136108 Haumea	HAU	1425	0.232 0.116	2003	1379	3.9154	Hiʻiaka (Haumea I)	2005	320	49880	49.462
							Namaka (Haumea II)	2005	170	25657	18.2783
136199 Eris	SDO	2326	0.301	2003	2326	378.6	Dysnomia (Eris I)	2005	700	37460	15.7859
136472 Makemake	CUB	1440	0.122	2005	1430	7.771	S/2015 (136472) 1	2015	130	21100+	12.4
	PLU	179	0.867	2001	135	13.7744	S/2004 (139775) 1	2003	117	172	0.5739
148780 Altjira	CUB	331	0.899	2001	246	–	S/2007 (148780) 1	2006	221	9904	139.56
	CUB	74	0.759	2000	153	–	S/2007 (160091) 1	2007	56	7695	347.085
	CUB	242	0.832	2002	186	–	S/2007 (160256) 1	2007	155	24400	470
174567 Varda	CUB	792	0.513	2003	705	5.91	Ilmarë (Varda I)	2009	361	4800	5.7508
	SDO	231	0.631	2002	195	–	S/2006 (182933) 1	2006	123	2060	12
	PLU	727	0.1	2003	723	13.44	S/2005 (208996) 1	2005	72	7200	12
225088 Gonggong	3:10	1230	0.2	2007	1535	44.81	Xiangliu (Gonggong I)	2010	95	15000	6
229762 Gǃkúnǁʼhòmdímà	SDO	599	0.175	2007	590	11.05	Gǃòʼé ǃHú (Gǃkúnǁʼhòmdímà I)	2008	71	3600	5.9
	CUB	229	0.912	2001	169	11.68	S/2006 (275809) 1	2006	154	9960	138.11
	CUB	265	0.603	2005	227	–	S/2007 (303712) 1	2007	137	3600	22
341520 Mors–Somnus	PLU	141	0.955	2007	102	9.28	Somnus	2007	97	21040	971.7
	CUB	145	0.637	2006	122	–	S/2006 (364171) 1	2006	78	33000	1500
385446 Manwë	4:7	185	0.58	2003	160	–	Thorondor (Manwë I)	2006	92	6674	110.176
	3:5	133	0.711	2001	108	–	S/2008 (469420) 1	2008	77	1200	12
	1:2	221	0.735	2003	178	5.85	S/2010 (469505) 1	2010	131	2140	14
	CUB	306	0.95	2003	222	–	S/2020 (469509) 1	2020	211	1960	-
	CUB	260	0.955	2003	188	–	S/2006 (469514) 1	2006	180	1900	9.1
	CUB	242	0.81	2004	188	–	S/2019 (469610) 1	2019	153	3820	29
469705 ǂKá̦gára	CUB	174	0.762	2005	138	9.65	ǃHãunu (ǂKá̦gára I)	2009	105	7700	128.11
	CUB	231	0.81	2013	180	–	S/2017 (505447) 1	2017	146	13300	200
	CUB	212	0.79	2013	166	–	S/2019 (505476) 1	2019	131	5370	59
	CUB	253	0.90	2016	188	6.85	S/2017 (506121) 1	2017	169	11300	140
	CUB	175	0.871	2000	132	–	S/2003 (508788) 1	2003	115	6930	220.7
	CUB	324	0.817	2002	251	–	S/2008 (508869) 1	2008	205	2490	9.8
	CUB	201	0.35	2013	190	–	S/2017 (511551) 1	2017	66	21400	460
	SDO	350	0.83	2008	270	–	S/2012 (523624) 1	2012	220	1300	3.3
	PLU	227	0.76	2011	181	–	S/2018 (523764) 1	2018	138	349	0.87
	CUB	146	0.605	1999	125	–	S/2008 (523764) 1	2008	76	1500	15
	CUB	140	0.832	2001	108	–	S/2001 (524217) 1	2001	90	1560	17
	CUB	221	0.826	2001	171	–	S/2005 (524366) 1	2006	140	9310	125.58
	CUB	350	0.619	2002	298	–	S/2008 (524531) 1	2008	185	19900	190
	CUB	171	0.513	2005	152.4	–	S/2005 (525462) 1	2005	78	69800	3579
	SDO	765	0.25	2013	740	–	S/2018 (532037) 1	2018	190	9800	15
	CUB	146	0.871	1998	110	–	S/2007 (1998 WV24) 1	2007	96	1420	14
	CUB	192	0.833	1998	148	–	S/2000 (1998 WW31) 1	2000	123	22620	587.3
	CUB	104	0.96	1999	75	–	S/2002 (612095) 1	2002	72	3267	84.12
	CUB	121	0.689	1999	100	–	S/2006 (1999 RT214) 1	2006	69	3310	64
	CUB	278	0.839	1999	213	–	S/2008 (612141) 1	2008	179	2670	14
	CUB	81	0.78	2000	63.6	–	S/2002 (612147) 1	2002	50	33300	3989
	1:2	206	0.967	2000	148	–	S/2006 (612176) 1	2006	143	5002	56.451
	CUB	265	0.82	2000	205	–	S/2008 (612203) 1	2008	168	2600	14
	CUB	167	0.617	2001	142	–	S/2006 (2001 FL185) 1	2006	88	1900	17
	CUB	303	0.817	2001	235	7.78	S/2002 (612239) 1	2002	192	3813	19.23
	CUB	231	0.912	2001	171	–	S/2007 (612242) 1	2007	156	3890	32
	CUB	180	0.986	2001	128	–	S/2001 (2001 QW322) 1	2001	126	102100	6280
	CUB	160	0.867	2002	121	–	S/2008 (2002 VF130) 1	2008	105	22400	760
	CUB	221	1	2003	156	–	S/2010 (612549) 1	2010	156	13200	210
	CUB	114	0.986	2003	81	3.4	S/2003 (2003 QY90) 1	2003	80	8549	309.7
	CUB	280	0.912	2003	207	–	S/2007 (612578) 1	2007	189	1790	7.5
	CUB	83	0.787	2003	65	–	S/2006 (2003 TJ58) 1	2006	51	3840	137.68
	CUB	149	0.667	2003	124	–	S/2003 (612687) 1	2003	83	54000	3180
	CUB	220-	0.724	2003	178	–	S/2007 (612719) 1	2007	129	1300	6.5
	CUB	167	0.871	2003	126	–	S/2008 (2003 YS179) 1	2008	110	7830	150
	CUB	167	0.55	2003	146	–	S/2008 (612733) 1	2008	80	2000	18
	CUB	319	0.85	2004	243	8+	S/2019 (2004 HD79) 1	2019	206	2780	12
	CUB	183	1.0	2004	129	–	S/2019 (2004 HK79) 1	2019	129	3600	41
	PLU	146	0.95	2004	105	–	S/2012 (2004 KB19) 1	2012	100	3400	53
	CUB	221	0.67	2004	184	–	S/2019 (2004 KE19) 1	2019	123	4110	36
	CUB	221	0.721	2004	179	–	S/2011 (2004 KH19) 1	2011	129	13000	210
	CUB	175	0.89	2004	131	2.5+	S/2019 (2004 MU8) 1	2019	116	5840	89
	CUB	277	0.544	2004	243	–	S/2006 (2004 PB108) 1	2006	132	10400	97.02
	CUB	221	0.44	2004	203	–	S/2019 (2004 PV117) 1	2019	89	6800	73
	CUB	242	0.72	2004	196	–	S/2019 (2004 PW117) 1	2019	141	23190	430
	CUB	221	0.81	2004	172	–	S/2019 (2004 PX117) 1	2019	139	5940	64
	CUB	160	0.832	2005	123	–	S/2009 (2005 GD187) 1	2009	102	7600	150
	CUB	133	0.398	2005	124	–	S/2008 (2005 VZ122) 1	2008	49	2300	30
	CUB	114	0.794	2006	89.8	–	S/2006 (2006 BR284) 1	2006	71	25300	1501
	CUB	129	0.817	2006	100	–	S/2004 (2006 CH69) 1	2004	82	27000	1420
	CUB	211	0.76	2006	168	–	S/2019 (2006 JV58) 1	2019	127	4340	43
	1:3	201	0.977	2006	144	–	S/2007 (2006 SF369) 1	2007	141	3120	28
	CUB	320	0.83	2014	250	–	S/2016 (671468) 1	2016	210	24000	290
	CUB	180	0.9	2015	130	–	S/2017 (2015 QL14) 1	2017	120	52000	2300
	CUB	134	0.76	2015	107	–	S/2019 (2015 RB280) 1	2019	81	6700	160
	CUB	154	0.76	2015	123	–	S/2019 (2015 RP280) 1	2019	93	5080	86
	CUB	222	0.95	2015	161	–	S/2019 (2015 RT245) 1	2019	153	14680	250
	CUB	265	0.87	2015	200	–	S/2019 (2015 VM173) 1	2019	174	5290	41
	CUB	106	0.76	2015	84	–	S/2019 (2015 VW168) 1	2019	64	5960	190
HST5	–	190	1	2005	135	–	n.a.	2005	135	16400	1000	—

See also

• Lists of astronomical objects
  • • Satellite system (astronomy)

External links

• • , Lecture at SETI talk Orbits of Binary Asteroids with Adaptive Optics (Franck Marchis)
• Satellites and Companions of Minor Planets (CBAT)
• Asteroids with Satellites Johnston's Archive
• The VOBAD database a web page built and designed by F. Marchis and his collaborators (UC-Berkeley/SETI Institute) which contains the parameters of 169 multiple asteroid systems (last update May 9, 2009)

Notes and References

1. Web site: Ninth asteroid added to Lucy mission; optimism grows on solar array issue. 14 June 2022. Clark, Stephen. Spaceflight Now. 15 June 2022.