Plutoid

A plutoid or ice dwarf is a dwarf planet that orbits the sun farther than Neptune. This concept was defined by the International Astronomical Union General Assembly on Prague under votes, but without choosing the terminology according to resolution 6A of this general assembly entitled Definition of Pluto-class objects. Its definition is:

Celestial bodies orbiting the Sun at a distance greater than that of Neptune, with sufficient mass for their own gravity to overcome rigid body forces such that they assume an almost spherical shape of hydrostatic equilibrium and that have not emptied their orbit of neighboring bodies.

Therefore, any object that meets the definition of dwarf planet and also belongs to the Trans-Neptunian objects will be considered a plutoid. Eight objects are now classified as plutoids: Pluto, Orcus, Haumea, Makemake, Quaoar, Sedna, Gonggong, and Eris.

The satellites of the plutoids are not plutoids, even though they are massive enough to be gravitationally rounded.

Ceres is not a plutoid hence it's in the asteroid belt between Mars and Jupiter and is the only dwarf planet that is not a plutoid.

Brightest objects

The plutinos brighter than H_V=6 include:

Object	a (AU)	q (AU)	i (°)	H	Diameter (km)	Albedo	V−R	Discovery year	Discoverer	Refs
134340 Pluto	39.3	29.7	17.1	−0.7	2376.6	0.49–0.66		1930	Clyde Tombaugh	JPL
90482 Orcus	39.2	30.3	20.6	2.31±0.03	917±25	0.28±0.06	0.37	2004	M. Brown, C. Trujillo, D. Rabinowitz	JPL
208996 Achlys	39.4	32.3	13.6	3.760±0.058	772±12	0.097±0.009	0.38±0.04	2003	M. Brown, C. Trujillo	JPL
28978 Ixion	39.7	30.1	19.6	3.845±0.006	696.78+10.75 −8.87	0.106±0.003	0.61	2001	Deep Ecliptic Survey	JPL
(455502) 2003 UZ₄₁₃	39.2	30.4	12.0	4.38±0.05	≈ 600	?	0.46±0.06	2001	M. Brown, C. Trujillo, D. Rabinowitz	JPL
(678191) 2017 OF₆₉	39.5	31.3	13.6	4.6	≈ 380–680	?	?	2017	D. J. Tholen, S. S. Sheppard, C. Trujillo	JPL
(84922) 2003 VS₂	39.3	36.4	14.8	4.14±0.07	524±7	0.134±0.010	0.59±0.02	2003	NEAT	JPL
(612533) 2002 XV₉₃	39.3	34.5	13.3	4.73	470+44 −30	0.040+0.020 −0.015	0.37±0.02	2001	M.W.Buie	JPL
(578993) 2014 JP₈₀	39.5	36.7	19.4	4.9	≈ 240–670	?	?	2014	Pan-STARRS	JPL
(84719) 2002 VR₁₂₈	39.3	28.9	14.0	5.58±0.37	448.5+42.1 −43.2	0.052+0.027 −0.018	0.60±0.02	2002	NEAT	JPL
(556068) 2014 JR₈₀	39.5	36.0	15.4	4.9	≈ 240–670	?	?	2014	Pan-STARRS	JPL
38628 Huya	39.4	28.5	15.5	5.04±0.03	414.7±0.9	0.079±0.004	0.57±0.09	2000	Ignacio Ferrin	JPL
(469372) 2001 QF₂₉₈	39.3	34.9	22.4	5.43±0.07	408.2+40.2 −44.9	0.071+0.020 −0.014	0.39±0.06	2001	Marc W. Buie	JPL
47171 Lempo	39.3	30.6	8.4	5.41±0.10	393.1+25.2 −26.8 (combined diameter of triple system)	0.079+0.013 −0.011	0.70±0.03	1999	E. P. Rubenstein, L.-G. Strolger	JPL
(469987) 2006 HJ₁₂₃	39.3	27.4	12.0	5.32±0.66	283.1+142.3 −110.8	0.136+0.308 −0.089		2006	Marc W. Buie	JPL
(307463) 2002 VU₁₃₀	39.3	31.2	14.0	5.47±0.83	252.9+33.6 −31.3	0.179+0.202 −0.103		2002	Marc W. Buie	JPL
(55638) 2002 VE₉₅	39.4	30.4	16.3	5.70±0.06	249.8+13.5 −13.1	0.149+0.019 −0.016	0.72±0.05	2002	NEAT	Plutoid Media Near true-colour image of Pluto and its moon Charon. Separation to scale 4 Vesta, an asteroid that was once a dwarf planet Euler diagram showing the IAU Executive Committee conception of the types of bodies in the Solar System (except the Sun) Comparison of sizes, albedos, and colours of various large trans-Neptunian objects with sizes of >700 km. The dark-coloured arcs represent uncertainties of the object's size. Relative densities and albedos of the most likely dwarf planets Ceres symbol (fixed width) Pluto monogram (fixed width) Quaoar symbol (fixed width) Sedna symbol (fixed width) Orcus symbol (fixed width) JPL

(link to all of the orbits of these objects listed above are here)

Plutoid

Brightest objects

Plutoid Media

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