Editing Trans-Neptunian object (section)

=== SDOs ===
The [[scattered disc]] contains objects farther from the Sun, with very eccentric and inclined orbits. These orbits are non-resonant and non-planetary-orbit-crossing. A typical example is the most-massive-known TNO, [[Eris (dwarf planet)|Eris]]. Based on the [[Tisserand parameter]] relative to Neptune (T<sub>N</sub>), the objects in the scattered disc can be further divided into the "typical" scattered disc objects (SDOs, Scattered-near) with a T<sub>N</sub> of less than 3, and into the [[detached objects]] (ESDOs, Scattered-extended) with a T<sub>N</sub> greater than 3. In addition, detached objects have a time-averaged eccentricity greater than 0.2<ref name="DES_Elliot2006">{{cite journal|first1=J. L. |last1=Elliot |first2=S. D. |last2=Kern |first3=K. B. |last3=Clancy |first4=A. A. S. |last4=Gulbis |first5=R. L. |last5=Millis |first6=M. W. |last6=Buie |first7=L. H. |last7=Wasserman |first8=E. I. |last8=Chiang |first9=A. B. |last9=Jordan |first10=D. E. |last10=Trilling |first11=K. J. |last11=Meech|title=The Deep Ecliptic Survey: A Search for Kuiper Belt Objects and Centaurs. II. Dynamical Classification, the Kuiper Belt Plane, and the Core Population|journal=The Astronomical Journal|volume=129|date=2005|pages=1117–1162|doi=10.1086/427395|bibcode=2005AJ....129.1117E|issue=2|doi-access=free }}</ref> The [[Sednoids]] are a further extreme sub-grouping of the detached objects with [[perihelia]] so distant that it is confirmed that their orbits cannot be explained by [[Perturbation (astronomy)|perturbations]] from the [[giant planet]]s,<ref name="brown2004">{{cite journal
 |first1=Michael E. |last1=Brown |author-link=Michael E. Brown |first2=Chadwick A. |last2=Trujillo |first3=David L. |last3=Rabinowitz
 |date=2004
 |title=Discovery of a Candidate Inner Oort Cloud Planetoid
 |url=http://www.gps.caltech.edu/classes/ge133/reading/sedna.pdf
 |archive-url=https://web.archive.org/web/20060627200056/http://www.gps.caltech.edu/classes/ge133/reading/sedna.pdf
 |archive-date=2006-06-27
 |journal=[[Astrophysical Journal]]
 |volume=617 |issue=1 |pages=645–649
 |arxiv = astro-ph/0404456
 |bibcode=2004ApJ...617..645B
 |doi=10.1086/422095
 |s2cid=7738201 |access-date=2008-04-02
}}</ref> nor by interaction with the [[galactic tide]]s.<ref name="nature letter">{{Cite journal |doi=10.1038/nature13156 |title=A Sedna-like body with a perihelion of 80 astronomical units |url=http://home.dtm.ciw.edu/users/sheppard/pub/TrujilloSheppard2014.pdf |archive-url=https://web.archive.org/web/20141216183818/http://home.dtm.ciw.edu/users/sheppard/pub/TrujilloSheppard2014.pdf |archive-date=2014-12-16 |url-status=live |journal=Nature |volume=507 |issue=7493 |pages=471–474 |year=2014 |last1=Trujillo |first1=Chadwick A. |author-link=Chadwick A. Trujillo |last2=Sheppard |first2=Scott S. |bibcode = 2014Natur.507..471T |pmid=24670765|s2cid=4393431 }}</ref> However, a [[Passing star hypothesis|passing star]] could have moved them on their orbit.<ref>{{Cite journal |last1=Pfalzner |first1=Susanne |last2=Govind |first2=Amith |last3=Portegies Zwart |first3=Simon |date=2024-09-04 |title=Trajectory of the stellar flyby that shaped the outer Solar System |journal=Nature Astronomy |volume=8 |issue=11 |language=en |pages=1380–1386 |doi=10.1038/s41550-024-02349-x |issn=2397-3366|doi-access=free |arxiv=2409.03342 |bibcode=2024NatAs...8.1380P }}</ref>