Editing Plutino (section)

== Orbits ==
[[Image:ThePlutinos Size Albedo Color2.svg|thumb|right|210px|Some of the largest known plutinos compared in size, [[albedo]] and [[color index|colour]]]]

=== Origin ===
It is thought that the objects that are currently in mean [[orbital resonance]]s with Neptune initially followed a variety of independent heliocentric paths. As Neptune migrated outward early in the Solar System's history (see [[Kuiper belt#Origin|origins of the Kuiper belt]]), the bodies it approached would have been scattered; during this process, some of them would have been captured into resonances.<ref name="Malhotra1995">{{cite journal |last1=Malhotra |title=The Origin of Pluto's Orbit: Implications for the Solar System Beyond Neptune |journal=Astronomical Journal |volume=110 |year=1995 |page=420 |arxiv = astro-ph/9504036 |bibcode = 1995AJ....110..420M |doi = 10.1086/117532 |first1= Renu|s2cid= 10622344}}</ref> The 3:2 resonance is a low-order resonance and is thus the strongest and most stable among all resonances.<ref>{{cite journal|last1=Almeida|first1=A.J.C|last2=Peixinho|first2=N.|last3=Correia|first3=A.C.M. |url=https://www.researchgate.net/publication/45876510|title=Neptune Trojans & Plutinos: Colors, sizes, dynamics, & their possible collisions|date=December 2009|journal=Astronomy & Astrophysics|doi=10.1051/0004-6361/200911943|volume=508|issue=2|pages=1021–1030|access-date=2019-07-20|arxiv=0910.0865|s2cid=53772214}}</ref> This is the primary reason it has a larger population than the other Neptunian resonances encountered in the Kuiper Belt. The cloud of low-inclination bodies beyond 40 [[Astronomical unit|AU]] is the [[Classical Kuiper belt object|cubewano]] family, while bodies with higher [[Orbital eccentricity|eccentricities]] (0.05 to 0.34) and [[Semi-major and semi-minor axes|semimajor axes]] close to the 3:2 Neptune resonance are primarily plutinos.<ref>{{cite book|url=https://books.google.com/books?id=QpcKesJwp28C&pg=PA411|first=John S.|publisher=Academic Press|department=Centaurs & Trans-Neptunian Objects|last=Lewis|isbn=012446744X |title=Physics & Chemistry of the Solar System|date=2004|pages=409–412|access-date=2019-07-21}}</ref>

=== Orbital characteristics ===
[[File:Plutino distributions and sizes.png|thumb|The distribution of Plutinos, and relative sizes, drawn 1 million times larger.]]
While the majority of plutinos have relatively low [[orbital inclination]]s, a significant fraction of these objects follow orbits similar to that of Pluto, with inclinations in the 10–25° range and eccentricities around 0.2–0.25; such orbits result in many of these objects having [[perihelion|perihelia]] close to or even inside Neptune's orbit, while simultaneously having [[aphelion|aphelia]] that bring them close to the main [[Kuiper belt]]'s outer edge (where objects in a 1:2 resonance with Neptune, the Twotinos, are found).

The orbital periods of plutinos cluster around 247.3 years (1.5 × Neptune's orbital period), varying by at most a few years from this value.

Unusual plutinos include:
* [[List of unnumbered trans-Neptunian objects: 2005#2005 TV189|{{mp|2005 TV|189}}]], which follows the most highly inclined orbit (34.5°)
*{{mpl|(15875) 1996 TP|66}}, which has the most elliptical orbit (its eccentricity is 0.33), with the perihelion halfway between Uranus and Neptune
*{{mpl|(470308) 2007 JH|43}} following a quasi-circular orbit
* [[List of unnumbered trans-Neptunian objects: 2002#2002 VX130|{{mp|2002 VX|130}}]] lying almost perfectly on the [[ecliptic]] (inclination less than 1.5°)
*[[15810 Arawn]], a [[quasi-satellite]] of Pluto<ref name=analemma>{{cite journal |title=The analemma criterion: accidental quasi-satellites are indeed true quasi-satellites |first1=Carlos |last1=de la Fuente Marcos |last2=de la Fuente Marcos |first2=Raúl |journal=[[Monthly Notices of the Royal Astronomical Society]] |date=2016 |volume=462 |issue=3 |pages=3344–3349 |arxiv=1607.06686 |doi=10.1093/mnras/stw1833 |doi-access=free |bibcode=2016MNRAS.462.3344D}}</ref>

See also the comparison with the [[cubewano#Distribution|distribution of the cubewanos]].

=== Long-term stability ===
Pluto's influence on the other plutinos has historically been neglected due to its relatively small mass. However, the resonance width (the range of semi-axes compatible with the resonance) is very narrow and only a few times larger than Pluto's [[Hill sphere]] (gravitational influence). Consequently, depending on the original eccentricity, some plutinos will eventually be driven out of the resonance by [[Perturbation (astronomy)|interactions]] with Pluto.<ref name=wan2001>{{cite journal
  | author=Wan, X.-S
  |author2=Huang, T.-Y.
   | title=The orbit evolution of 32 plutinos over 100 million year
  | journal=Astronomy and Astrophysics
  | volume=368
  | issue=2 | pages=700–705 | year=2001
  | bibcode=2001A&A...368..700W| doi = 10.1051/0004-6361:20010056
| doi-access=free}}</ref>  Numerical simulations suggest that the orbits of plutinos with an eccentricity 10%–30% smaller or larger than that of Pluto are not stable over [[Giga-annum|Ga]] timescales.<ref name="Yu1999">{{cite journal |first1=Qingjuan |last1=Yu |first2=Scott |last2=Tremaine |title=The Dynamics of Plutinos |journal=Astronomical Journal |volume=118 |year=1999 |issue= 4|pages=1873–1881 |arxiv = astro-ph/9904424 |bibcode = 1999AJ....118.1873Y |doi = 10.1086/301045 |s2cid=14482507 }}</ref>