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{{About|planets not gravitationally bound to a star}}
{{short description|Planets not gravitationally bound to a star}}
{{Use dmy dates|date=April 2024}}
[[File:Artist's impression of the free-floating planet CFBDSIR J214947.2-040308.9.ogv|thumb|300px|This video shows an artist's impression of the free-floating planet [[CFBDSIR 2149−0403|CFBDSIR J214947.2-040308.9]]. ]]

A '''rogue planet''', also termed a '''free-floating planet''' ('''FFP''') or an '''isolated planetary-mass object''' ('''iPMO'''), is an [[interstellar object]] of [[planetary-mass object|planetary mass]] which is not gravitationally bound to any [[star]] or [[brown dwarf]].<ref name="shostak">{{cite web |last=Shostak |first=Seth |date=24 February 2005 |title=Orphan Planets: It's a Hard Knock Life |url=https://www.space.com/818-orphan-planets-hard-knock-life.html |access-date=13 November 2020 |website=Space.com}}</ref><ref name="lloyd">{{cite web |last=Lloyd |first=Robin |date=18 April 2001 |title=Free-Floating Planets – British Team Restakes Dubious Claim |url=http://www.space.com/scienceastronomy/astronomy/free_floaters_010403-1.html |url-status=dead |archive-url=https://web.archive.org/web/20081013054054/http://www.space.com/scienceastronomy/astronomy/free_floaters_010403-1.html |archive-date=13 October 2008 |website=Space.com}}</ref><ref>{{cite web |date=18 April 2001 |title=Orphan 'planet' findings challenged by new model |url=http://astrobiology.arc.nasa.gov/news/expandnews.cfm?id%3D783 |url-status=dead |archive-url=https://web.archive.org/web/20090322091340/http://astrobiology.arc.nasa.gov/news/expandnews.cfm?id=783 |archive-date=22 March 2009 |publisher=NASA Astrobiology}}</ref><ref name=":4">{{Cite journal |last1=Kirkpatrick |first1=J. Davy |last2=Gelino |first2=Christopher R. |last3=Faherty |first3=Jacqueline K. |last4=Meisner |first4=Aaron M. |last5=Caselden |first5=Dan |last6=Schneider |first6=Adam C. |last7=Marocco |first7=Federico |last8=Cayago |first8=Alfred J. |last9=Smart |first9=R. L. |last10=Eisenhardt |first10=Peter R. |last11=Kuchner |first11=Marc J. |last12=Wright |first12=Edward L. |last13=Cushing |first13=Michael C. |last14=Allers |first14=Katelyn N. |last15=Bardalez Gagliuffi |first15=Daniella C. |date=2021-03-01 |title=The Field Substellar Mass Function Based on the Full-sky 20 pc Census of 525 L, T, and Y Dwarfs |journal=The Astrophysical Journal Supplement Series |volume=253 |issue=1 |pages=7 |doi=10.3847/1538-4365/abd107 |arxiv=2011.11616 |bibcode=2021ApJS..253....7K |issn=0067-0049 |doi-access=free }}</ref>

Rogue planets may originate from [[Planetary system|planetary systems]] in which they are formed and later ejected, or they can also form on their own, outside a planetary system. The [[Milky Way]] alone may have billions to trillions of rogue planets, a range the upcoming [[Nancy Grace Roman Space Telescope]] will likely be able to narrow.<ref>[[Neil deGrasse Tyson]] in ''[[Cosmos: A Spacetime Odyssey]]'' as referred to by [https://web.archive.org/web/20140313190543/http://phenomena.nationalgeographic.com/2014/03/13/a-guide-to-lonely-planets-in-the-galaxy/ ''National Geographic'']</ref><ref>"The research team found that the mission will provide a rogue planet count that is at least 10 times more precise than current estimates, which range from tens of billions to trillions in our galaxy." https://scitechdaily.com/our-solar-system-may-be-unusual-rogue-planets-unveiled-with-nasas-roman-space-telescope/</ref>

Some planetary-mass objects may have formed in a similar way to stars, and the [[International Astronomical Union]] has proposed that such objects be called [[sub-brown dwarf]]s.<ref>[http://www.dtm.ciw.edu/boss/definition.html Working Group on Extrasolar Planets – Definition of a "Planet"] Position Statement on the Definition of a "Planet" (IAU) {{webarchive|url=https://web.archive.org/web/20060916161707/http://www.dtm.ciw.edu/boss/definition.html |date=16 September 2006}}</ref> A possible example is [[Cha 110913−773444]], which may either have been ejected and become a rogue planet or formed on its own to become a sub-brown dwarf.<ref name="CNN">[http://edition.cnn.com/2000/TECH/space/10/06/space.planets.reut/index.html "Rogue planet find makes astronomers ponder theory"]</ref>

== Terminology ==
The two first discovery papers use the names isolated planetary-mass objects (iPMO)<ref name=":10" /> and free-floating planets (FFP).<ref name=":14" /> Most astronomical papers use one of these terms.<ref name=":15" /><ref name=":16" /><ref name=":17" /> The term rogue planet is more often used for microlensing studies, which also often uses the term FFP.<ref name=":18">{{cite journal |last1=Bennett |first1=D.P. |last2=Batista |first2=V. |display-authors=etal |date=13 December 2013 |title=A Sub-Earth-Mass Moon Orbiting a Gas Giant Primary or a High Velocity Planetary System in the Galactic Bulge |journal=The Astrophysical Journal |volume=785 |issue=2 |pages=155 |arxiv=1312.3951 |bibcode=2014ApJ...785..155B |doi=10.1088/0004-637X/785/2/155 |s2cid=118327512}}</ref><ref name="Mróz2020" /> A [[press release]] intended for the public might use an alternative name. The discovery of at least 70 FFPs in 2021, for example, used the terms rogue planet,<ref name="eso2120" /> starless planet,<ref>{{Cite web |date=2021-12-23 |title=Billions of Starless Planets Haunt Dark Cloud Cradles |url=https://www.nao.ac.jp/en/news/science/2021/20211223-subaru.html |access-date=2023-09-09 |website=NAOJ: National Astronomical Observatory of Japan |language=en}}</ref> wandering planet<ref name=":19" /> and free-floating planet<ref>{{Cite web |title=Largest Collection of Free-Floating Planets Found in the Milky Way - KPNO |url=https://kpno.noirlab.edu/news/noirlab2131/ |access-date=2023-09-08 |website=kpno.noirlab.edu}}</ref> in different press releases.

== Discovery ==
Isolated planetary-mass objects (iPMO) were first discovered in 2000 by the [[United Kingdom|UK]] team Lucas & Roche with [[United Kingdom Infrared Telescope|UKIRT]] in the [[Orion Nebula]].<ref name=":14">{{Cite journal |last1=Lucas |first1=P. W. |last2=Roche |first2=P. F. |date=2000-06-01 |title=A population of very young brown dwarfs and free-floating planets in Orion |journal=Monthly Notices of the Royal Astronomical Society |volume=314 |issue=4 |pages=858–864 |doi=10.1046/j.1365-8711.2000.03515.x |doi-access=free |arxiv=astro-ph/0003061 |bibcode=2000MNRAS.314..858L |s2cid=119002349 |issn=0035-8711}}</ref> In the same year the [[Spain|Spanish]] team Zapatero Osorio et al. discovered iPMOs with [[W. M. Keck Observatory|Keck]] spectroscopy in the [[Sigma Orionis#Cluster|σ Orionis cluster]].<ref name=":10" /> The spectroscopy of the objects in the Orion Nebula was published in 2001.<ref name=":11" /> Both [[Europe|European]] teams are now recognized for their quasi-simultaneous discoveries.<ref name=":7" /> In 1999 the [[Japan|Japanese]] team Oasa ''et al.'' discovered objects in [[Chamaeleon complex|Chamaeleon I]]<ref>{{Cite journal |last1=Oasa |first1=Yumiko |last2=Tamura |first2=Motohide |last3=Sugitani |first3=Koji |date=1999-11-01 |title=A Deep Near-Infrared Survey of the Chamaeleon I Dark Cloud Core |journal=The Astrophysical Journal |volume=526 |issue=1 |pages=336–343 |doi=10.1086/307964 |bibcode=1999ApJ...526..336O |s2cid=120597899 |issn=0004-637X|doi-access=free }}</ref> that were spectroscopically confirmed years later in 2004 by the [[United States|US]] team Luhman et al.<ref>{{Cite journal |last1=Luhman |first1=K. L. |last2=Peterson |first2=Dawn E. |last3=Megeath |first3=S. T. |date=2004-12-01 |title=Spectroscopic Confirmation of the Least Massive Known Brown Dwarf in Chamaeleon |url=https://ui.adsabs.harvard.edu/abs/2004ApJ...617..565L |journal=The Astrophysical Journal |volume=617 |issue=1 |pages=565–568 |doi=10.1086/425228 |arxiv=astro-ph/0411445 |bibcode=2004ApJ...617..565L |s2cid=18157277 |issn=0004-637X}}</ref>

== Observation ==
[[File:Locations of the rogue planets.jpg|thumb|115 potential rogue planets in the region between Upper Scorpius and Ophiuchus (2021)]]

There are two techniques to discover free-floating planets: direct imaging and microlensing.

=== Microlensing ===
Astrophysicist Takahiro Sumi of Osaka University in Japan and colleagues, who form the [[Microlensing Observations in Astrophysics]] and the [[Optical Gravitational Lensing Experiment]] collaborations, published their study of [[microlensing]] in 2011. They observed 50 million stars in the Milky Way by using the {{convert|1.8|m|adj=on}} MOA-II telescope at New Zealand's [[Mount John Observatory]] and the {{convert|1.3|m|adj=on}} [[University of Warsaw]] telescope at Chile's [[Las Campanas Observatory]]. They found 474 incidents of microlensing, ten of which were brief enough to be planets of around Jupiter's size with no associated star in the immediate vicinity. The researchers estimated from their observations that there are nearly two Jupiter-mass rogue planets for every star in the Milky Way.<ref>[http://news.sciencemag.org/sciencenow/2011/05/homeless-planets-may-be-common.html?ref=hp Homeless' Planets May Be Common in Our Galaxy] {{webarchive | url=https://web.archive.org/web/20121008190445/http://news.sciencemag.org/sciencenow/2011/05/homeless-planets-may-be-common.html?ref=hp | date=8 October 2012}} by Jon Cartwright, Science Now, 18 May 2011, Accessed 20 May 2011</ref><ref>[http://www.physorg.com/news/2011-05-class-planets.html Planets that have no stars: New class of planets discovered], Physorg.com, 18 May 2011. Accessed May 2011.</ref><ref>{{cite journal|first=T. |last=Sumi |arxiv=1105.3544 |title=Unbound or Distant Planetary Mass Population Detected by Gravitational Microlensing |date=2011 |display-authors=etal |doi=10.1038/nature10092 |pmid=21593867 |volume=473 |issue=7347 |journal=Nature |pages=349–352 |bibcode=2011Natur.473..349S |s2cid=4422627}}</ref> One study suggested a much larger number, up to 100,000 times more rogue planets than stars in the Milky Way, though this study encompassed hypothetical objects much smaller than Jupiter.<ref>{{cite web|title=Researchers say galaxy may swarm with 'nomad planets' |url=https://www6.slac.stanford.edu/news/2012-02-23-researchers-say-galaxy-may-swarm-nomad-planets |access-date=29 February 2012 |publisher=[[Stanford University]]|date=2012-02-23}}</ref> A 2017 study by Przemek Mróz of Warsaw University Observatory and colleagues, with six times larger statistics than the 2011 study, indicates an upper limit on Jupiter-mass free-floating or wide-orbit planets of 0.25 planets per main-sequence star in the Milky Way.<ref>{{cite journal|author=P. Mroz |arxiv=1707.07634 |title=No large population of unbound or wide-orbit Jupiter-mass planets |date=2017 |display-authors=etal |doi=10.1038/nature23276 |pmid=28738410 |volume=548 |issue=7666 |journal=Nature |pages=183–186 |bibcode=2017Natur.548..183M|s2cid=4459776}}</ref>

In September 2020, astronomers using [[Gravitational microlensing|microlensing techniques]] reported the [[Microlensing Observations in Astrophysics|detection]], for the first time, of an [[Terrestrial planet|Earth-mass]] rogue planet (named [[OGLE-2016-BLG-1928]]) unbound to any star and free floating in the [[Milky Way]] galaxy.<ref name="Mróz2020">{{cite journal |last1=Mróz |first1=Przemek |last2=Poleski |first2=Radosław |last3=Gould |first3=Andrew |last4=Udalski |first4=Andrzej |last5=Sumi |first5=Takahiro |last6=Szymański |first6=Michał K. |last7=Soszyński |first7=Igor |last8=Pietrukowicz |first8=Paweł |last9=Kozłowski |first9=Szymon |last10=Skowron |first10=Jan |last11=Ulaczyk |first11=Krzysztof |last12=Albrow |first12=Michael D. |last13=Chung |first13=Sun-Ju |last14=Han |first14=Cheongho |last15=Hwang |first15=Kyu-Ha |display-authors=1 |year=2020 |title=A Terrestrial-mass Rogue Planet Candidate Detected in the Shortest-timescale Microlensing Event |journal=The Astrophysical Journal Letters |volume=903 |issue=1 |at=L11 |arxiv=2009.12377 |bibcode=2020ApJ...903L..11M |doi=10.3847/2041-8213/abbfad |bibcode-access=free |doi-access=free |last16=Jung |first16=Youn Kil |last17=Kim |first17=Hyoun-Woo |last18=Ryu |first18=Yoon-Hyun |last19=Shin |first19=In-Gu |last20=Shvartzvald |first20=Yossi |last21=Yee |first21=Jennifer C. |last22=Zang |first22=Weicheng |last23=Cha |first23=Sang-Mok |last24=Kim |first24=Dong-Jin |last25=Kim |first25=Seung-Lee |last26=Lee |first26=Chung-Uk |last27=Lee |first27=Dong-Joo |last28=Lee |first28=Yongseok |last29=Park |first29=Byeong-Gon |last30=Pogge |first30=Richard W.}}</ref><ref name="UT-20201001">{{cite news |last=Gough |first=Evan |date=1 October 2020 |title=A Rogue Earth-Mass Planet Has Been Discovered Freely Floating in the Milky Way Without a Star |work=[[Universe Today]] |url=https://www.universetoday.com/148097/a-rogue-earth-mass-planet-has-been-discovered-freely-floating-in-the-milky-way-without-a-star/ |access-date=2 October 2020}}</ref><ref name="SA-20201019a">{{cite news|last=Redd |first=Nola Taylor |title=Rogue Rocky Planet Found Adrift in the Milky Way – The diminutive world and others like it could help astronomers probe the mysteries of planet formation |url=https://www.scientificamerican.com/article/rogue-rocky-planet-found-adrift-in-the-milky-way/|date=19 October 2020 |work=[[Scientific American]] |access-date=19 October 2020}}</ref>



=== Direct imaging ===
[[File:WISE J0830+2837 Spitzer.jpg|thumb|The cold planetary-mass object WISE J0830+2837 (marked orange object) observed with the [[Spitzer Space Telescope]]. It has a temperature of 300-350 [[Kelvin|K]] (27-77[[Celsius|°C]]; 80-170 [[Fahrenheit|°F]]).]]
Microlensing planets can only be studied by the microlensing event, which makes the characterization of the planet difficult. Astronomers therefore turn to isolated planetary-mass objects (iPMO) that were found via the [[Methods of detecting exoplanets#Direct imaging|direct imaging method]]. To determine a mass of a [[brown dwarf]] or iPMO one needs for example the luminosity and the age of an object.<ref>{{Cite journal |last1=Saumon |first1=D. |last2=Marley |first2=Mark S. |date=2008-12-01 |title=The Evolution of L and T Dwarfs in Color-Magnitude Diagrams |url=https://ui.adsabs.harvard.edu/abs/2008ApJ...689.1327S |journal=The Astrophysical Journal |volume=689 |issue=2 |pages=1327–1344 |doi=10.1086/592734 |arxiv=0808.2611 |bibcode=2008ApJ...689.1327S |s2cid=15981010 |issn=0004-637X}}</ref> Determining the age of a low-mass object has proven to be difficult. It is no surprise that the vast majority of iPMOs are found inside young nearby [[Star formation|star-forming regions]] of which astronomers know their age. These objects are younger than 200 Myrs, are massive (>5 {{Jupiter mass|link=true}})<ref name=":4" /> and belong to the [[L dwarf|L-]] and [[T dwarf|T-dwarfs]].<ref name=":5" /><ref name=":6" /> There is however a small growing sample of cold and old [[Y dwarf|Y-dwarfs]] that have estimated masses of 8-20 {{Jupiter mass}}.<ref>{{Cite journal |last1=Leggett |first1=S. K. |last2=Tremblin |first2=P. |last3=Esplin |first3=T. L. |last4=Luhman |first4=K. L. |last5=Morley |first5=Caroline V. |date=2017-06-01 |title=The Y-type Brown Dwarfs: Estimates of Mass and Age from New Astrometry, Homogenized Photometry, and Near-infrared Spectroscopy |journal=The Astrophysical Journal |volume=842 |issue=2 |pages=118 |doi=10.3847/1538-4357/aa6fb5 |arxiv=1704.03573 |bibcode=2017ApJ...842..118L |issn=0004-637X |doi-access=free }}</ref> Nearby rogue planet candidates of spectral type Y include [[WISE 0855−0714]] at a distance of {{val|7.27|0.13|u=light-years}}.<ref name="Luhman2016">{{cite journal|title=The Spectral Energy Distribution of the Coldest Known Brown Dwarf |journal=The Astronomical Journal |first1=Kevin L. |last1=Luhman |first2=Taran L. |last2=Esplin |volume=152 |issue=2 |at=78 |date=September 2016 |doi=10.3847/0004-6256/152/3/78 |bibcode=2016AJ....152...78L |arxiv=1605.06655|s2cid=118577918 |doi-access=free }}</ref> If this sample of Y-dwarfs can be characterized with more accurate measurements or if a way to better characterize their ages can be found, the number of old and cold iPMOs will likely increase significantly.

The first iPMOs were discovered in the early 2000s via direct imaging inside young star-forming regions.<ref name=":9" /><ref name=":10" /><ref name=":11" /> These iPMOs found via direct imaging formed probably like stars (sometimes called sub-brown dwarf). There might be iPMOs that form like a planet, which are then ejected. These objects will however be [[Stellar kinematics|kinematically]] different from their natal star-forming region, should not be surrounded by a [[Circumstellar disc|circumstellar disk]] and have high [[metallicity]].<ref name=":7">{{Cite journal |last=Caballero |first=José A. |date=2018-09-01 |title=A Review on Substellar Objects below the Deuterium Burning Mass Limit: Planets, Brown Dwarfs or What? |journal=Geosciences |volume=8 |issue=10 |pages=362 |doi=10.3390/geosciences8100362 |arxiv=1808.07798 |bibcode=2018Geosc...8..362C |doi-access=free }}</ref> None of the iPMOs found inside young star-forming regions show a high velocity compared to their star-forming region. For old iPMOs the cold [[WISE J0830+2837]]<ref name=":8" /> shows a V<sub>tan</sub> of about 100 km/s, which is high, but still consistent with formation in our galaxy. For [[WISE 1534–1043]]<ref>{{Cite journal |last1=Kirkpatrick |first1=J. Davy |last2=Marocco |first2=Federico |last3=Caselden |first3=Dan |last4=Meisner |first4=Aaron M. |last5=Faherty |first5=Jacqueline K. |last6=Schneider |first6=Adam C. |last7=Kuchner |first7=Marc J. |last8=Casewell |first8=S. L. |last9=Gelino |first9=Christopher R. |last10=Cushing |first10=Michael C. |last11=Eisenhardt |first11=Peter R. |last12=Wright |first12=Edward L. |last13=Schurr |first13=Steven D. |date=2021-07-01 |title=The Enigmatic Brown Dwarf WISEA J153429.75-104303.3 (a.k.a. "The Accident") |journal=The Astrophysical Journal |volume=915 |issue=1 |pages=L6 |doi=10.3847/2041-8213/ac0437 |arxiv=2106.13408 |bibcode=2021ApJ...915L...6K |issn=0004-637X |doi-access=free }}</ref> one alternative scenario explains this object as an ejected exoplanet due to its high V<sub>tan</sub> of about 200 km/s, but its color suggests it is an old metal-poor brown dwarf. Most astronomers studying massive iPMOs believe that they represent the low-mass end of the star-formation process.<ref name=":7" />

Astronomers have used the [[Herschel Space Observatory]] and the [[Very Large Telescope]] to observe a very young free-floating planetary-mass object, [[OTS 44]], and demonstrate that the processes characterizing the canonical star-like mode of formation apply to isolated objects down to a few Jupiter masses. Herschel [[Far-infrared astronomy|far-infrared observations]] have shown that OTS 44 is surrounded by a disk of at least 10 Earth masses and thus could eventually form a mini planetary system.<ref name="joergens2013_AA558">{{cite journal |last1=Joergens |first1=V. |last2=Bonnefoy |first2=M. |last3=Liu |first3=Y. |last4=Bayo |first4=A. |last5=Wolf |first5=S. |last6=Chauvin |first6=G. |last7=Rojo |first7=P. |date=2013 |title=OTS 44: Disk and accretion at the planetary border |journal=Astronomy & Astrophysics |volume=558 |page=L7 |arxiv=1310.1936 |bibcode=2013A&A...558L...7J |doi=10.1051/0004-6361/201322432 |s2cid=118456052 |number=7}}</ref> Spectroscopic observations of OTS 44 with the SINFONI spectrograph at the Very Large Telescope have revealed that the disk is actively accreting matter, similar to the disks of young stars.<ref name="joergens2013_AA558" />

===Binaries===
{{multiple image
 | align = right
 | direction = vertical
 | width = 200
 | image1 = TWA 42 Keck.png
 | caption1 = 2MASS J1119–1137AB, the first planetary-mass binary discovered, located in the [[TW Hydrae association]]
 | image2 = JuMBO 29.jpg
 | caption2 = JuMBO 29, a candidate 12.5+3 {{jupiter mass}} binary, separated by 135 [[astronomical unit|AU]], located in the Orion Nebula
}}
The first discovery of a resolved planetary-mass binary was [[2MASS J11193254–1137466 AB|2MASS J1119–1137AB]]. There are however other binaries known, such as [[2MASS J1553022+153236AB]],<ref>{{Cite journal |last1=Dupuy |first1=Trent J. |last2=Liu |first2=Michael C. |date=2012-08-01 |title=The Hawaii Infrared Parallax Program. I. Ultracool Binaries and the L/T Transition |journal=The Astrophysical Journal Supplement Series |volume=201 |issue=2 |pages=19 |arxiv=1201.2465 |bibcode=2012ApJS..201...19D |doi=10.1088/0067-0049/201/2/19 |issn=0067-0049 |doi-access=free}}</ref><ref name=":26">{{Cite journal |last1=Zhang |first1=Zhoujian |last2=Liu |first2=Michael C. |last3=Best |first3=William M. J. |last4=Dupuy |first4=Trent J. |last5=Siverd |first5=Robert J. |date=2021-04-01 |title=The Hawaii Infrared Parallax Program. V. New T-dwarf Members and Candidate Members of Nearby Young Moving Groups |journal=The Astrophysical Journal |volume=911 |issue=1 |pages=7 |arxiv=2102.05045 |bibcode=2021ApJ...911....7Z |doi=10.3847/1538-4357/abe3fa |issn=0004-637X |doi-access=free}}</ref> [[WISE 1828+2650]], [[WISE 0146+4234]], [[WISE J0336−0143]] (could also be a [[brown dwarf]] and a [[planetary-mass object]] (BD+PMO) binary), [[NIRISS-NGC1333-12]]<ref>{{Cite journal |last1=Langeveld |first1=Adam B. |last2=Scholz |first2=Aleks |last3=Mužić |first3=Koraljka |last4=Jayawardhana |first4=Ray |last5=Capela |first5=Daniel |last6=Albert |first6=Loïc |last7=Doyon |first7=René |last8=Flagg |first8=Laura |last9=de Furio |first9=Matthew |last10=Johnstone |first10=Doug |last11=Lafrèniere |first11=David |last12=Meyer |first12=Michael |date=2024-10-01 |title=The JWST/NIRISS Deep Spectroscopic Survey for Young Brown Dwarfs and Free-floating Planets |journal=The Astronomical Journal |volume=168 |issue=4 |pages=179 |arxiv=2408.12639 |bibcode=2024AJ....168..179L |doi=10.3847/1538-3881/ad6f0c |doi-access=free |issn=0004-6256}}</ref> and several objects discovered by Zhang et al.<ref name=":26" />

In the [[Orion Nebula]] a population of 40 wide binaries and 2 triple systems were discovered. This was surprising for two reasons: The trend of [[Brown dwarf#Binary brown dwarfs|binaries of brown dwarfs]] predicted a decrease of distance between low mass objects with decreasing mass. It was also predicted that the binary fraction decreases with mass. These binaries were named Jupiter-mass binary objects (JuMBOs). They make up at least 9% of the iPMOs and have a separation smaller than 340 [[Astronomical unit|AU]].<ref name=":21"/> It is unclear how these JuMBOs formed, but an extensive study argued that they formed in situ, like stars.<ref>{{Cite journal | last1=Portegies Zwart| first1=Simon|last2=Hochart|first2=Erwan|date=2024-07-02|title=The origin and evolution of wide Jupiter mass binary objects in young stellar clusters| journal=SciPost| volume=3|issue=1|pages=19|doi=10.21468/SciPostAstro.3.1.001| doi-access=free| arxiv=2312.04645| bibcode=2024ScPA....3....1P}}</ref> If they formed like stars, then there must be an unknown "extra ingredient" to allow them to form. If they formed like planets and were later ejected, then it has to be explained why these binaries did not break apart during the ejection process. Future measurements with JWST might resolve if these objects formed as ejected planets or as stars.<ref name=":21">{{Cite arXiv |last1=Pearson |first1=Samuel G. |last2=McCaughrean |first2=Mark J. |date=2 Oct 2023 |title=Jupiter Mass Binary Objects in the Trapezium Cluster |pages=24 |class=astro-ph.EP |eprint=2310.01231 }}</ref> A study by [[Kevin Luhman]] reanalysed the [[NIRCam]] data and found that most JuMBOs did not appear in his sample of substellar objects. Moreover the color were consistent with reddened background sources or low signal-to-noise sources. Only [[JuMBO 29]] is identified as a good candidate in this work.<ref name="Luhman2024">{{cite arXiv| last = Luhman | first =K. L. | author-link=Kevin Luhman| date =14 Oct 2024 | title =Candidates for Substellar Members of the Orion Nebula Cluster from JWST/NIRCam | eprint =2410.10406 | class = astro-ph}}</ref> JuMBO 29 also was observed with [[NIRSpec]] and one component was identified as a young M8 source.<ref name="Luhman2024b">{{cite arXiv| last1 = Luhman | first1 =K. L. | author-link=Kevin Luhman| first2=C. |last2=Alves de Oliveira |first3=I. |last3=Baraffe |author-link3=Isabelle Baraffe |first4=G. |last4=Chabrier |author-link4=Gilles Chabrier |first5=E. |last5=Manjavacas |first6=R. J. |last6=Parker |first7=P. |last7=Tremblin | date =13 Oct 2024 | title =JWST/NIRSpec Observations of Brown Dwarfs in the Orion Nebula Cluster | eprint =2410.10000 | class = astro-ph}}</ref> This spectral type is consistent with a low mass for the age of the Orion Nebula.<ref name="Luhman2024" />

=== Total number of known iPMOs ===
There are likely hundreds<ref name="Miret-Roig2021" /><ref name=":21" /> of known candidate iPMOs, over a hundred<ref>{{Cite book |last1=Béjar |first1=V. J. S. |url=https://ui.adsabs.harvard.edu/abs/2018haex.bookE..92B |title=Brown Dwarfs and Free-Floating Planets in Young Stellar Clusters |last2=Martín |first2=Eduardo L. |date=2018-01-01|bibcode=2018haex.bookE..92B }}</ref><ref name=":2" /><ref name=":20" /> objects with spectra and a small but growing number of candidates discovered via microlensing. Some large surveys include:

As of December 2021, the largest-ever group of rogue planets was discovered, numbering at least 70 and up to 170 depending on the assumed age. They are found in the [[OB association]] between [[Upper Scorpius association|Upper Scorpius]] and [[Ophiuchus]] with masses between 4 and 13 {{Jupiter mass|link=y}} and age around 3 to 10 million years, and were most likely formed by either [[gravitational collapse]] of gas clouds, or formation in a [[protoplanetary disk]] followed by ejection due to [[Planetary migration#Gravitational scattering|dynamical instabilities]].<ref name="Miret-Roig2021">{{Cite journal|last1=Miret-Roig|first1=Núria|last2=Bouy|first2=Hervé|last3=Raymond|first3=Sean N.|last4=Tamura|first4=Motohide|last5=Bertin|first5=Emmanuel|last6=Barrado|first6=David|last7=Olivares|first7=Javier|last8=Galli|first8=Phillip A. B.|last9=Cuillandre|first9=Jean-Charles|last10=Sarro|first10=Luis Manuel|last11=Berihuete|first11=Angel|date=2021-12-22|title=A rich population of free-floating planets in the Upper Scorpius young stellar association|url=https://www.nature.com/articles/s41550-021-01513-x|journal=Nature Astronomy|volume=6|pages=89–97|language=en|doi=10.1038/s41550-021-01513-x|issn=2397-3366|bibcode=2022NatAs...6...89M|arxiv=2112.11999|s2cid=245385321}} See also
[https://www.nature.com/articles/s41550-021-01513-x.epdf?sharing_token=q1qRU1u0E-F1gidMR-zy99RgN0jAjWel9jnR3ZoTv0MNRjP5-PHrAStec6uGZjltVbis6xlDrJ6k1jF8hqqq10sjBO3UdEZIpgGDRm7TPS_gSCK_FYKPReCzFKzmtRjs42WI3U-Sq54AafvVIZd1723041mlBJXX5KXeJj4Y7aQ%3D Nature SharedIt article link];
[https://www.eso.org/public/archives/releases/sciencepapers/eso2120/eso2120a_en.pdf ESO article link]</ref><ref name="eso2120">{{cite web | title = ESO telescopes help uncover largest group of rogue planets yet | url = https://www.eso.org/public/news/eso2120/ | publisher = [[European Southern Observatory]] | date = 22 December 2021 | access-date = 22 December 2021}}</ref><ref>{{Cite web|last1=Raymond|first1=Sean|last2=Bouy|first2=Núria Miret-Roig & Hervé|date=2021-12-22|title=We Discovered a Rogues' Gallery of Monster-Sized Gas Giants|url=http://nautil.us/blog/we-discovered-a-rogues-gallery-of-monster_sized-gas-giants|access-date=2021-12-23|website=Nautilus}}</ref><ref name=":19">{{Cite web|last=Shen|first=Zili|date=2021-12-30|title=Wandering Planets|url=https://astrobites.org/2021/12/30/free-floating-planets/|access-date=2022-01-02|website=Astrobites|language=en-US}}</ref> Follow-up observations with spectroscopy from the [[Subaru Telescope]] and [[Gran Telescopio Canarias]] showed that the contamination of this sample is quite low (≤6%). The 16 young objects had a mass between 3 and 14 {{Jupiter mass}}, confirming that they are indeed planetary-mass objects.<ref name=":20" />

In October 2023 an even larger group of 540 planetary-mass object candidates was discovered in the Trapezium Cluster and inner Orion Nebula with JWST. The objects have a mass between 13 and 0.6 {{Jupiter mass}}. A surprising number of these objects formed wide binaries, which was not predicted.<ref name=":21" />

== Formation ==
There are in general two scenarios that can lead to the formation of an isolated planetary-mass object (iPMO). It can form like a planet around a star and is then ejected, or it forms like a low-mass star or brown dwarf in isolation. This can influence its composition and motion.<ref name=":7" />

=== Formation like a star ===
{{Main|Sub-brown dwarf}}
Objects with a mass of at least one [[Jupiter mass]] were thought to be able to form via collapse and fragmentation of [[Molecular cloud|molecular clouds]] from models in 2001.<ref>{{Cite journal |last=Boss |first=Alan P. |date=2001-04-01 |title=Formation of Planetary-Mass Objects by Protostellar Collapse and Fragmentation |journal=The Astrophysical Journal |volume=551 |issue=2 |pages=L167–L170 |doi=10.1086/320033 |bibcode=2001ApJ...551L.167B |s2cid=121261733 |issn=0004-637X|doi-access=free }}</ref> Pre-JWST observations have shown that objects below 3-5 {{Jupiter mass}} are unlikely to form on their own.<ref name=":4" /> Observations in 2023 in the [[Trapezium Cluster]] with JWST have shown that objects as massive as 0.6 {{Jupiter mass}} might form on their own, not requiring a steep cut-off mass.<ref name=":21" /> A particular type of [[Evaporating gaseous globule|globule]], called [[globulettes]], are thought to be birthplaces for brown dwarfs and planetary-mass objects. Globulettes are found in the [[Rosette Nebula]] and [[Heart Nebula|IC 1805]].<ref>{{Cite journal |last1=Gahm |first1=G. F. |last2=Grenman |first2=T. |last3=Fredriksson |first3=S. |last4=Kristen |first4=H. |date=2007-04-01 |title=Globulettes as Seeds of Brown Dwarfs and Free-Floating Planetary-Mass Objects |journal=The Astronomical Journal |volume=133 |issue=4 |pages=1795–1809 |doi=10.1086/512036 |bibcode=2007AJ....133.1795G |s2cid=120588285 |issn=0004-6256|doi-access=free }}</ref> Sometimes young iPMOs are still surrounded by a disk that could form [[Exomoon|exomoons]]. Due to the tight orbit of this type of exomoon around their host planet, they have a high chance of 10-15% to be [[Astronomical transit|transiting]].<ref name=":12">{{Cite journal |last1=Limbach |first1=Mary Anne |last2=Vos |first2=Johanna M. |last3=Winn |first3=Joshua N. |last4=Heller |first4=René |last5=Mason |first5=Jeffrey C. |last6=Schneider |first6=Adam C. |last7=Dai |first7=Fei |date=2021-09-01 |title=On the Detection of Exomoons Transiting Isolated Planetary-mass Objects |journal=The Astrophysical Journal |volume=918 |issue=2 |pages=L25 |doi=10.3847/2041-8213/ac1e2d |arxiv=2108.08323 |bibcode=2021ApJ...918L..25L |issn=0004-637X |doi-access=free }}</ref>

==== Disks ====
Some very young star-forming regions, typically younger than 5 million years, sometimes contain isolated planetary-mass objects with infrared excess and signs of [[Accretion (astrophysics)|accretion]]. Most well known is the iPMO [[OTS 44]] discovered to have a [[Circumstellar disc|disk]] and being located in [[Chamaeleon complex|Chamaeleon I]]. Charmaeleon I and II have other candidate iPMOs with disks.<ref>{{Cite journal |last1=Luhman |first1=K. L. |last2=Adame |first2=Lucía |last3=D'Alessio |first3=Paola |last4=Calvet |first4=Nuria |last5=Hartmann |first5=Lee |last6=Megeath |first6=S. T. |last7=Fazio |first7=G. G. |date=2005-12-01 |title=Discovery of a Planetary-Mass Brown Dwarf with a Circumstellar Disk |journal=The Astrophysical Journal |volume=635 |issue=1 |pages=L93–L96 |doi=10.1086/498868 |bibcode=2005ApJ...635L..93L |issn=0004-637X|doi-access=free |arxiv=astro-ph/0511807 }}</ref><ref name=":22">{{Cite journal |last1=Jayawardhana |first1=Ray |last2=Ivanov |first2=Valentin D. |date=2006-08-01 |title=Spectroscopy of Young Planetary Mass Candidates with Disks |journal=The Astrophysical Journal |volume=647 |issue=2 |pages=L167–L170 |doi=10.1086/507522 |bibcode=2006ApJ...647L.167J |issn=0004-637X|doi-access=free |arxiv=astro-ph/0607152 }}</ref><ref name=":5" /> Other star-forming regions with iPMOs with disks or accretion are Lupus I,<ref name=":22" /> [[Rho Ophiuchi cloud complex|Rho Ophiuchi Cloud Complex]],<ref name=":23">{{Cite journal |last1=Rilinger |first1=Anneliese M. |last2=Espaillat |first2=Catherine C. |date=2021-11-01 |title=Disk Masses and Dust Evolution of Protoplanetary Disks around Brown Dwarfs |journal=The Astrophysical Journal |volume=921 |issue=2 |pages=182 |doi=10.3847/1538-4357/ac09e5 |bibcode=2021ApJ...921..182R |issn=0004-637X |doi-access=free |arxiv=2106.05247 }}</ref> Sigma Orionis cluster,<ref>{{Cite journal |last1=Zapatero Osorio |first1=M. R. |last2=Caballero |first2=J. A. |last3=Béjar |first3=V. J. S. |last4=Rebolo |first4=R. |last5=Barrado Y Navascués |first5=D. |last6=Bihain |first6=G. |last7=Eislöffel |first7=J. |last8=Martín |first8=E. L. |last9=Bailer-Jones |first9=C. A. L. |last10=Mundt |first10=R. |last11=Forveille |first11=T. |last12=Bouy |first12=H. |date=2007-09-01 |title=Discs of planetary-mass objects in σ Orionis |journal=Astronomy and Astrophysics |volume=472 |issue=1 |pages=L9–L12 |doi=10.1051/0004-6361:20078116 |bibcode=2007A&A...472L...9Z |issn=0004-6361|doi-access=free }}</ref> Orion Nebula,<ref name=":24" /> [[Taurus molecular cloud|Taurus]],<ref name=":23" /><ref>{{Cite journal |last1=Best |first1=William M. J. |last2=Liu |first2=Michael C. |last3=Magnier |first3=Eugene A. |last4=Bowler |first4=Brendan P. |last5=Aller |first5=Kimberly M. |last6=Zhang |first6=Zhoujian |last7=Kotson |first7=Michael C. |last8=Burgett |first8=W. S. |last9=Chambers |first9=K. C. |last10=Draper |first10=P. W. |last11=Flewelling |first11=H. |last12=Hodapp |first12=K. W. |last13=Kaiser |first13=N. |last14=Metcalfe |first14=N. |last15=Wainscoat |first15=R. J. |date=2017-03-01 |title=A Search for L/T Transition Dwarfs with Pan-STARRS1 and WISE. III. Young L Dwarf Discoveries and Proper Motion Catalogs in Taurus and Scorpius-Centaurus |journal=The Astrophysical Journal |volume=837 |issue=1 |pages=95 |doi=10.3847/1538-4357/aa5df0 |bibcode=2017ApJ...837...95B |issn=0004-637X |doi-access=free |arxiv=1702.00789 |hdl=1721.1/109753 |hdl-access=free }}</ref> [[NGC 1333]]<ref>{{Cite journal |last1=Scholz |first1=Aleks |last2=Muzic |first2=Koraljka |last3=Jayawardhana |first3=Ray |last4=Almendros-Abad |first4=Victor |last5=Wilson |first5=Isaac |date=2023-05-01 |title=Disks around Young Planetary-mass Objects: Ultradeep Spitzer Imaging of NGC 1333 |journal=The Astronomical Journal |volume=165 |issue=5 |pages=196 |doi=10.3847/1538-3881/acc65d |bibcode=2023AJ....165..196S |issn=0004-6256 |doi-access=free |arxiv=2303.12451 |hdl=10023/27429 |hdl-access=free }}</ref> and [[IC 348]].<ref>{{Cite journal |last1=Alves de Oliveira |first1=C. |last2=Moraux |first2=E. |last3=Bouvier |first3=J. |last4=Duchêne |first4=G. |last5=Bouy |first5=H. |last6=Maschberger |first6=T. |last7=Hudelot |first7=P. |date=2013-01-01 |title=Spectroscopy of brown dwarf candidates in IC 348 and the determination of its substellar IMF down to planetary masses |journal=Astronomy and Astrophysics |volume=549 |pages=A123 |doi=10.1051/0004-6361/201220229 |bibcode=2013A&A...549A.123A |issn=0004-6361|doi-access=free |arxiv=1211.4029 }}</ref> A large survey of disks around brown dwarfs and iPMOs with [[Atacama Large Millimeter Array|ALMA]] found that these disks are not massive enough to form [[Terrestrial planet|earth-mass]] planets. There is still the possibility that the disks already have formed planets.<ref name=":23" /> Studies of [[Red dwarf|red dwarfs]] have shown that some have gas-rich disks at a relative old age. These disks were dubbed [[Peter Pan disk|Peter Pan Disks]] and this trend could continue into the planetary-mass regime. One Peter Pan disk is the 45 Myr old brown dwarf [[2MASS J02265658-5327032]] with a mass of about 13.7 {{Jupiter mass}}, which is close to the planetary-mass regime.<ref>{{Cite journal |last1=Boucher |first1=Anne |last2=Lafrenière |first2=David |last3=Gagné |first3=Jonathan |last4=Malo |first4=Lison |last5=Faherty |first5=Jacqueline K. |last6=Doyon |first6=René |last7=Chen |first7=Christine H. |date=2016-11-01 |title=BANYAN. VIII. New Low-mass Stars and Brown Dwarfs with Candidate Circumstellar Disks |journal=The Astrophysical Journal |volume=832 |issue=1 |pages=50 |doi=10.3847/0004-637X/832/1/50 |bibcode=2016ApJ...832...50B |issn=0004-637X |doi-access=free |arxiv=1608.08259 }}</ref> Recent studies of the nearby planetary-mass object [[2MASS J11151597+1937266]] found that this nearby iPMO is surrounded by a disk. It shows signs of accretion from the disk and also infrared excess.<ref name="Theissen2018">{{Cite journal |last1=Theissen |first1=Christopher A. |last2=Burgasser |first2=Adam J. |last3=Bardalez Gagliuffi |first3=Daniella C. |last4=Hardegree-Ullman |first4=Kevin K. |last5=Gagné |first5=Jonathan |last6=Schmidt |first6=Sarah J. |last7=West |first7=Andrew A. |date=2018-01-01 |title=2MASS J11151597+1937266: A Young, Dusty, Isolated, Planetary-mass Object with a Potential Wide Stellar Companion |journal=The Astrophysical Journal |volume=853 |issue=1 |pages=75 |arxiv=1712.03964 |bibcode=2018ApJ...853...75T |doi=10.3847/1538-4357/aaa0cf |issn=0004-637X |doi-access=free}}</ref>

=== Formation like a planet ===
Ejected planets are predicted to be mostly low-mass (<30 {{Earth mass|link=true}} Figure 1 Ma et al.)<ref name=":13">{{Cite journal |last1=Ma |first1=Sizheng |last2=Mao |first2=Shude |last3=Ida |first3=Shigeru |last4=Zhu |first4=Wei |last5=Lin |first5=Douglas N. C. |date=2016-09-01 |title=Free-floating planets from core accretion theory: microlensing predictions |journal=Monthly Notices of the Royal Astronomical Society |volume=461 |issue=1 |pages=L107–L111 |doi=10.1093/mnrasl/slw110 |doi-access=free |arxiv=1605.08556 |bibcode=2016MNRAS.461L.107M |issn=0035-8711}}</ref> and their mean mass depends on the mass of their host star. Simulations by Ma et al.<ref name=":13" /> did show that 17.5% of 1 {{Solar mass|link=true}} stars eject a total of 16.8 {{Earth mass}} per star with a typical ([[median]]) mass of 0.8 {{Earth mass}} for an individual free-floating planet (FFP). For lower mass [[Red dwarf|red dwarfs]] with a mass of 0.3 {{Solar mass}} 12% of stars eject a total of 5.1 {{Earth mass}} per star with a typical mass of 0.3 {{Earth mass}} for an individual FFP.

Hong et al.<ref>{{Cite journal |last1=Hong |first1=Yu-Cian |last2=Raymond |first2=Sean N. |last3=Nicholson |first3=Philip D. |last4=Lunine |first4=Jonathan I. |date=2018-01-01 |title=Innocent Bystanders: Orbital Dynamics of Exomoons During Planet-Planet Scattering |journal=The Astrophysical Journal |volume=852 |issue=2 |pages=85 |doi=10.3847/1538-4357/aaa0db |arxiv=1712.06500 |bibcode=2018ApJ...852...85H |issn=0004-637X |doi-access=free }}</ref> predicted that exomoons can be scattered by planet-planet interactions and become ejected exomoons. Higher mass (0.3-1 {{Jupiter mass}}) ejected FFP are predicted to be possible, but they are also predicted to be rare.<ref name=":13" /> Ejection of a planet can occur via planet-planet scatter or due a stellar flyby. Another possibility is the ejection of a fragment of a disk that then forms into a planetary-mass object.<ref name=":25">{{Cite journal |last=Miret-Roig |first=Núria |date=2023-03-01 |title=The origin of free-floating planets |url=https://ui.adsabs.harvard.edu/abs/2023Ap&SS.368...17M/abstract |journal=Astrophysics and Space Science |volume=368 |issue=3 |pages=17 |arxiv=2303.05522 |bibcode=2023Ap&SS.368...17M |doi=10.1007/s10509-023-04175-5 |issn=0004-640X}}</ref> Another suggested scenario is the ejection of planets in a tilted [[Circumbinary planet|circumbinary orbit]]. Interactions with the central binary and the planets with each other can lead to the ejection of the lower-mass planet in the system.<ref>{{Cite journal |last1=Chen |first1=Cheng |last2=Martin |first2=Rebecca G. |last3=Lubow |first3=Stephen H. |last4=Nixon |first4=C. J. |date=2024-01-01 |title=Tilted Circumbinary Planetary Systems as Efficient Progenitors of Free-floating Planets |journal=The Astrophysical Journal |volume=961 |issue=1 |pages=L5 |arxiv=2310.15603 |bibcode=2024ApJ...961L...5C |doi=10.3847/2041-8213/ad17c5 |doi-access=free |issn=0004-637X}}</ref>

=== Other scenarios ===
If a stellar or brown dwarf embryo experiences a halted accretion, it could remain low-mass enough to become a planetary-mass object. Such a halted accretion could occur if the embryo is ejected or if its circumstellar disk experiences [[photoevaporation]] near [[O-type star|O-stars]]. Objects that formed via the ejected embryo scenario would have smaller or no disk and the fraction of binaries decreases for such objects. It could also be that free-floating planetary-mass objects for from a combination of scenarios.<ref name=":25" />

== Fate ==
Most isolated planetary-mass objects will float in interstellar space forever.

Some iPMOs will have a close encounter with a [[planetary system]]. This rare encounter can have three outcomes: The iPMO will remain unbound, it could be weakly bound to the star, or it could "kick out" the exoplanet, replacing it. Simulations have shown that the vast majority of these encounters result in a capture event with the iPMO being weakly bound with a low [[gravitational binding energy]] and an elongated highly [[Orbital eccentricity|eccentric orbit]]. These orbits are not stable and 90% of these objects gain energy due to planet-planet encounters and are ejected back into interstellar space. Only 1% of all stars will experience this temporary capture.<ref>{{Cite journal |last1=Goulinski |first1=Nadav |last2=Ribak |first2=Erez N. |date=2018-01-01 |title=Capture of free-floating planets by planetary systems |journal=Monthly Notices of the Royal Astronomical Society |volume=473 |issue=2 |pages=1589–1595 |doi=10.1093/mnras/stx2506 |doi-access=free |bibcode=2018MNRAS.473.1589G |issn=0035-8711|arxiv=1705.10332 }}</ref>

== Warmth ==
[[File:Alone in Space - Astronomers Find New Kind of Planet.jpg|thumb|200px|Artist's conception of a [[Jupiter]]-size rogue planet]]
Interstellar planets generate little heat and are not heated by a star.<ref>{{cite web |url=https://aeon.co/essays/could-we-make-our-home-on-a-rogue-planet-without-a-sun |title=Life in the dark |publisher=Aeon |first=Sean |last=Raymond |date=9 April 2005 |access-date=9 April 2016}}</ref> However, in 1998, [[David J. Stevenson]] theorized that some planet-sized objects adrift in interstellar space might sustain a thick atmosphere that would not freeze out. He proposed that these atmospheres would be preserved by the pressure-induced far-[[infrared]] radiation opacity of a thick [[hydrogen]]-containing atmosphere.<ref name="Stevenson 1999">{{cite journal |journal=Nature |date=1999 |title=Life-sustaining planets in interstellar space? |first1=David J. |last1=Stevenson |doi=10.1038/21811 |volume=400 |page=32 |last2=Stevens |first2=C. F. |issue=6739 |bibcode=1999Natur.400...32S |pmid=10403246|s2cid=4307897|doi-access=free }}</ref>

During planetary-system formation, several small protoplanetary bodies may be ejected from the system.<ref>{{cite journal|last=Lissauer |first= J. J. |title=Timescales for Planetary Accretion and the Structure of the Protoplanetary disk |journal=Icarus |volume=69 |issue=2 |pages=249–265 |date=1987 |doi=10.1016/0019-1035(87)90104-7 |bibcode=1987Icar...69..249L |hdl=2060/19870013947 |hdl-access=free}}</ref> An ejected body would receive less of the stellar-generated [[ultraviolet]] light that can strip away the lighter elements of its atmosphere. Even an Earth-sized body would have enough gravity to prevent the escape of the hydrogen and helium in its atmosphere.<ref name="Stevenson 1999" /> In an Earth-sized object the [[geothermal energy]] from residual core radioisotope decay could maintain a surface temperature above the [[melting point]] of water,<ref name="Stevenson 1999" /> allowing liquid-water oceans to exist. These planets are likely to remain geologically active for long periods. If they have geodynamo-created protective [[magnetosphere]]s and sea floor volcanism, [[hydrothermal vent]]s could provide energy for life.<ref name="Stevenson 1999" /> These bodies would be difficult to detect because of their weak thermal microwave radiation emissions, although reflected solar radiation and [[Far-infrared astronomy|far-infrared]] thermal emissions may be detectable from an object that is less than 1,000 [[astronomical unit]]s from Earth.<ref>{{cite journal|title=The Steppenwolf: A proposal for a habitable planet in interstellar space |arxiv=1102.1108 |first1=Dorian S. |last1=Abbot |first2=Eric R. |last2=Switzer |date=2 June 2011 |doi=10.1088/2041-8205/735/2/L27 |volume=735 |issue=2 |journal=The Astrophysical Journal |page=L27 |bibcode=2011ApJ...735L..27A|s2cid=73631942 }}</ref> Around five percent of Earth-sized ejected planets with Moon-sized [[natural satellite]]s would retain their satellites after ejection.  A large satellite would be a source of significant geological [[tidal heating]].<ref>{{cite journal|title=The Survival Rate of Ejected Terrestrial Planets with Moons |first=John H. |last=Debes |author2=Steinn Sigurðsson |date=20 October 2007 |journal=The Astrophysical Journal Letters |volume=668 |issue=2 |pages=L167–L170 |doi=10.1086/523103 |bibcode=2007ApJ...668L.167D |arxiv=0709.0945 |s2cid=15782213}}</ref>

== List ==
The table below lists rogue planets, confirmed or suspected, that have been discovered. It is yet unknown whether these planets were ejected from orbiting a star or else formed on their own as [[sub-brown dwarf]]s. Whether exceptionally low-mass rogue planets (such as [[OGLE-2012-BLG-1323]] and [[KMT-2019-BLG-2073]]) are even capable of being formed on their own is currently unknown.

=== Discovered via direct imaging ===
These objects were discovered with the [[Methods of detecting exoplanets#Direct imaging|direct imaging]] method. Many were discovered in young [[Star cluster|star-clusters]] or [[Stellar association|stellar associations]] and a few old are known (such as [[WISE 0855−0714]]). List is sorted after discovery year.
{| class="wikitable sortable" style="margin:1em auto; text-align: center;"
! [[Exoplanet]]
! [[Planetary mass|Mass]]
({{Jupiter mass|link=y}})
! Age
(Myr)
! data-sort-type="number" | Distance
(ly)
![[Stellar classification|Spectral type]]
! Status
![[Stellar association|Stellar assoc.]] membership
! Discovery
|-
| [[OTS 44]] || {{sort|11.5|~11.5}} || 0.5–3 || 554
|M9.5|| Likely a [[Brown dwarf#Low-mass brown dwarfs versus high-mass planets|low-mass brown dwarf]]<ref name=":9">{{cite journal|title=Spitzer Identification of the Least Massive Known Brown Dwarf with a Circumstellar Disk |first=Kevin L. |last=Luhman |date=10 February 2005 |journal=[[Astrophysical Journal Letters]] |volume=620 |issue=1 |pages=L51–L54 |doi=10.1086/428613 |bibcode=2005ApJ...620L..51L |arxiv=astro-ph/0502100|s2cid=15340083}}</ref>
|[[Chamaeleon complex|Chamaeleon I]]|| 1998
|-
| [[S Ori 52]] || {{sort|05|2–8}} || 1–5 || data-sort-value="1150" |1,150
| || Age and mass uncertain; may be a foreground [[brown dwarf]]
|[[Sigma Orionis#Cluster|σ Orionis cluster]]|| 2000<ref name=":10">{{cite journal |title=Discovery of Young, Isolated Planetary Mass Objects in the σ Orionis Star Cluster |first=M. R. |last=Zapatero Osorio |date=6 October 2000 |journal=Science |volume=290 |issue=5489 |pages=103–7 |doi=10.1126/science.290.5489.103 |pmid=11021788 |bibcode=2000Sci...290..103Z}}</ref>
|-
|[[061-401|Proplyd 061-401]] || {{sort|11|~11}} || 1 || 1,344
|L4–L5
|Candidate, 15 candidates in total from this work
|[[Orion Nebula|Orion nebula]]
|2001<ref name=":11">{{Cite journal |last1=Lucas |first1=P. W. |last2=Roche |first2=P. F. |last3=Allard |first3=France |last4=Hauschildt |first4=P. H. |date=2001-09-01 |title=Infrared spectroscopy of substellar objects in Orion |journal=Monthly Notices of the Royal Astronomical Society |volume=326 |issue=2 |pages=695–721 |doi=10.1046/j.1365-8711.2001.04666.x |doi-access=free |arxiv=astro-ph/0105154 |bibcode=2001MNRAS.326..695L |s2cid=280663 |issn=0035-8711}}</ref>
|-
| [[S Ori 70]] || {{sort|03|3}} || 3|| 1150
|T6||interloper?<ref name=":7" />
|σ Orionis cluster|| 2002
|-
| [[Cha 110913-773444]] || {{sort|10|5–15}} || 2~ || 529
|data-sort-value="M9.5" |>M9.5|| Confirmed
|Chamaeleon I|| 2004<ref>{{cite journal |title=Discovery of a Planetary-Mass Brown Dwarf with a Circumstellar Disk |first=Kevin L. |last=Luhman |date=10 December 2005 |journal=[[Astrophysical Journal Letters]] |volume=635 |issue=1 |pages=L93–L96 |doi=10.1086/498868 |bibcode=2005ApJ...635L..93L |arxiv=astro-ph/0511807|s2cid=11685964}}</ref>
|-
| [[SIMP J013656.5+093347]] || {{sort|12|11-13}} || 200~ || 20-22
|T2.5|| Candidate
|[[List of nearby stellar associations and moving groups|Carina-Near moving group]]|| 2006<ref>{{cite journal|first1=Étienne |last1=Artigau |first2=René |last2=Doyon |first3=David |last3=Lafrenière |first4=Daniel |last4=Nadeau |title=Discovery of the Brightest T Dwarf in the Northern Hemisphere |url=https://stacks.iop.org/1538-4357/651/i=1/a=L57 |journal=The Astrophysical Journal Letters|date= n.d. |issn=1538-4357 |pages=L57 |volume=651 |issue=1 |doi=10.1086/509146 |first5=Jasmin |last5=Robert |first6=Loïc |last6=Albert |arxiv=astro-ph/0609419 |bibcode=2006ApJ...651L..57A |s2cid=118943169}}</ref><ref>{{cite journal|first1=Jonathan |last1=Gagné |first2=Jacqueline K. |last2=Faherty|author2-link=Jackie Faherty |first3=Adam J. |last3=Burgasser |first4=Étienne |last4=Artigau |title=SIMP J013656.5+093347 is Likely a Planetary-Mass Object in the Carina-Near Moving Group |journal=The Astrophysical Journal |date=15 May 2017 |issn=2041-8213 |pages=L1 |volume=841 |issue=1 |doi=10.3847/2041-8213/aa70e2 |first5=Sandie |last5=Bouchard |first6=Loïc |last6=Albert |first7=David |last7=Lafrenière |first8=René |last8=Doyon |first9=Daniella C. |last9=Bardalez-Gagliuffi |arxiv=1705.01625 |bibcode=2017ApJ...841L...1G |s2cid=119024210 |doi-access=free }}</ref>
|-
| [[UGPS J072227.51−054031.2]] || {{sort|08.34|0.66–16.02}}<ref name="Sanghi et al arxiv" /><ref name="Sanghi et al zenodo" />|| 1000 – 5000|| 13
|T9|| Mass uncertain
|none|| 2010
|-
| [[M10-4450]]|| {{sort|02.5|2–3}} || 1|| 325
|T|| Candidate
|[[Rho Ophiuchi cloud complex|rho Ophiuchi cloud]]|| 2010<ref>{{cite journal|title=A Young Planetary-Mass Object in the ρ Oph Cloud Core |first=Kenneth A. |last=Marsh |date=1 February 2010 |journal=[[Astrophysical Journal Letters]] |volume=709 |issue=2 |pages=L158–L162 |doi=10.1088/2041-8205/709/2/L158 |bibcode=2010ApJ...709L.158M |arxiv=0912.3774|s2cid=29098549}}</ref>
|-
| [[WISE 1828+2650]]
|{{nowrap|3–6 or 0.5–20<ref name="Beichman2013">{{cite journal | last=Beichman |first=C. |author2=Gelino, Christopher R. |author3=Kirkpatrick, J. Davy |author4=Barman, Travis S. |author5=Marsh, Kenneth A. |author6=Cushing, Michael C. |author7=Wright, E. L. | title=The Coldest Brown Dwarf (or Free-floating Planet)?: The Y Dwarf WISE 1828+2650 | date=2013 | journal=[[The Astrophysical Journal]] | volume=764 | issue=1 | pages=101 | arxiv=1301.1669 | doi=10.1088/0004-637X/764/1/101 | bibcode=2013ApJ...764..101B|s2cid=118575478 }}</ref>}}
|{{nowrap|2–4 or 0.1–10<ref name="Beichman2013" />}}
|47
|data-sort-value="Y2" |>Y2
|candidate, could be binary
|none
|2011
|-
| [[CFBDSIR 2149−0403]] || {{sort|05.5|4–7}} || 110–130 || 117–143
|T7|| Candidate
|[[AB Doradus moving group]]|| 2012<ref>{{cite journal|title=CFBDSIR2149-0403: a 4-7 Jupiter-mass free-floating planet in the young moving group AB Doradus? |first=Philippe |last=Delorme |date=25 September 2012 |journal=[[Astronomy & Astrophysics]] |volume=548A |page=26 |doi=10.1051/0004-6361/201219984 |bibcode=2012A&A...548A..26D |arxiv=1210.0305|s2cid=50935950}}</ref>
|-
|[[SONYC-NGC1333-36]]
| {{sort|06|~6}}
|1
|978
|L3
|candidate, NGC 1333 has two other objects with masses below 15 {{Jupiter mass}}
|[[NGC 1333]]
|2012<ref>{{Cite journal |last1=Scholz |first1=Alexander |last2=Jayawardhana |first2=Ray |last3=Muzic |first3=Koraljka |last4=Geers |first4=Vincent |last5=Tamura |first5=Motohide |last6=Tanaka |first6=Ichi |date=2012-09-01 |title=Substellar Objects in Nearby Young Clusters (SONYC). VI. The Planetary-mass Domain of NGC 1333 |url=https://ui.adsabs.harvard.edu/abs/2012ApJ...756...24S |journal=The Astrophysical Journal |volume=756 |issue=1 |pages=24 |doi=10.1088/0004-637X/756/1/24 |arxiv=1207.1449 |bibcode=2012ApJ...756...24S |s2cid=119251742 |issn=0004-637X}}</ref>
|-
|[[SSTc2d J183037.2+011837]]
|{{sort|03|2–4}}
|3
|848–1354
|T?
|Candidate, also called ID 4
|[[Serpens cluster|Serpens Core cluster]]<ref>{{Cite web |title=NAME Serpens Cluster |url=http://simbad.cds.unistra.fr/simbad/sim-id?Ident=%402656129&Name=NAME%20Serpens%20Cluster&submit=submit |access-date=2023-09-07 |website=simbad.cds.unistra.fr}}</ref> (in the [[Serpens–Aquila Rift|Serpens Cloud]])
|2012<ref name=":15">{{Cite journal |last1=Spezzi |first1=L. |last2=Alves de Oliveira |first2=C. |last3=Moraux |first3=E. |last4=Bouvier |first4=J. |last5=Winston |first5=E. |last6=Hudelot |first6=P. |last7=Bouy |first7=H. |last8=Cuillandre |first8=J. -C. |date=2012-09-01 |title=Searching for planetary-mass T-dwarfs in the core of Serpens |url=https://ui.adsabs.harvard.edu/abs/2012A&A...545A.105S |journal=Astronomy and Astrophysics |volume=545 |pages=A105 |doi=10.1051/0004-6361/201219559 |arxiv=1208.0702 |bibcode=2012A&A...545A.105S |s2cid=119232214 |issn=0004-6361}}</ref>
|-
| [[PSO J318.5−22]] || {{sort|06.92|6.24–7.60}}<ref name="Sanghi et al arxiv">{{Cite arXiv |last1=Sanghi |first1=Aniket |last2=Liu |first2=Michael C. |last3=Best |first3=William M. |last4=Dupuy |first4=Trent J. |last5=Siverd |first5=Robert J. |last6=Zhang |first6=Zhoujian |last7=Hurt |first7=Spencer A. |last8=Magnier |first8=Eugene A. |last9=Aller |first9=Kimberly M. |last10=Deacon |first10=Niall R. |date=6 September 2023 |title=The Hawaii Infrared Parallax Program. VI. The Fundamental Properties of 1000+ Ultracool Dwarfs and Planetary-mass Objects Using Optical to Mid-IR SEDs and Comparison to BT-Settl and ATMO 2020 Model Atmospheres |class=astro-ph.SR |eprint=2309.03082}}</ref><ref name="Sanghi et al zenodo">{{Cite journal |last1=Sanghi |first1=Aniket |last2=Liu |first2=Michael C. |last3=Best |first3=William M. |last4=Dupuy |first4=Trent J. |last5=Siverd |first5=Robert J. |last6=Zhang |first6=Zhoujian |last7=Hurt |first7=Spencer A. |last8=Magnier |first8=Eugene A. |last9=Aller |first9=Kimberly M. |last10=Deacon |first10=Niall R. |date=7 September 2023 |title=Table of Ultracool Fundamental Properties |url=https://zenodo.org/record/8315643 |journal=Zenodo |pages=1|doi=10.5281/zenodo.8315643 }}</ref>|| 21–27 || 72.32
|L7|| Confirmed; also known as 2MASS J21140802-2251358
|[[Beta Pictoris moving group|Beta Pictoris Moving group]]|| 2013<ref name=":17">{{cite journal|title=The Extremely Red, Young L Dwarf PSO J318.5338-22.8603: A Free-floating Planetary-mass Analog to Directly Imaged Young Gas-giant Planets |first=Michael C. |last=Liu |date=10 November 2013 |journal=[[Astrophysical Journal Letters]] |volume=777 |issue=1 |pages=L20 |doi=10.1088/2041-8205/777/2/L20 |bibcode=2013ApJ...777L..20L|arxiv=1310.0457|s2cid=54007072}}</ref><ref>{{Cite journal|last1=Filippazzo|first1=Joseph C.|last2=Rice|first2=Emily L.|last3=Faherty|first3=Jacqueline|last4=Cruz|first4=Kelle L.|last5=Van Gordon|first5=Mollie M.|last6=Looper|first6=Dagny L.|date=2015-09-01|title=Fundamental Parameters and Spectral Energy Distributions of Young and Field Age Objects with Masses Spanning the Stellar to Planetary Regime|url=https://ui.adsabs.harvard.edu/abs/2015ApJ...810..158F|journal=The Astrophysical Journal|volume=810|issue=2|pages=158|doi=10.1088/0004-637X/810/2/158|arxiv=1508.01767|bibcode=2015ApJ...810..158F|s2cid=89611607|issn=0004-637X}}</ref>
|-
| [[2MASS J2208+2921]]|| {{sort|12|11–13}} || 21–27 || 115
|L3γ|| Candidate; radial velocity needed
|Beta Pictoris Moving group|| 2014<ref>{{cite journal|title=BANYAN. II. Very Low Mass and Substellar Candidate Members to Nearby, Young Kinematic Groups with Previously Known Signs of Youth |first=Jonathan |last=Gagné |date=10 March 2014 |journal=[[Astrophysical Journal]] |volume=783 |issue=2 |page=121 |doi=10.1088/0004-637X/783/2/121 |bibcode=2014ApJ...783..121G |arxiv=1312.5864|s2cid=119251619}}</ref>
|-
| [[WISE J1741-4642]]|| {{sort|12.5|4–21}} || 23–130 ||
|L7pec|| Candidate
|Beta Pictoris or AB Doradus moving group|| 2014<ref>{{cite journal |title=Discovery of the Young L Dwarf WISE J174102.78-464225.5 |first=Adam C. |last=Schneider |date=9 January 2014 |journal=[[Astronomical Journal]] |volume=147 |issue=2 |page=34 |doi=10.1088/0004-6256/147/2/34 |bibcode=2014AJ....147...34S |arxiv=1311.5941|s2cid=38602758}}</ref>
|-
| [[WISE 0855−0714]]|| {{sort|6.5|3–10}} || data-sort-value="1000" |>1,000
| 7.1
|Y4|| Age uncertain, but old due to solar vicinity object;<ref>{{Cite journal|last1=Zapatero Osorio |first1=M. R. |last2=Lodieu |first2=N.|last3=Béjar |first3=V. J. S. |last4=Martín |first4=Eduardo L. |last5=Ivanov |first5=V. D. |last6=Bayo |first6=A.|last7=Boffin |first7=H. M. J. |last8=Muzic |first8=K. |last9=Minniti |first9=D. |last10=Beamín |first10=J. C. |date=2016-08-01 |title=Near-infrared photometry of WISE J085510.74-071442.5 |bibcode=2016A&A...592A..80Z |journal=Astronomy and Astrophysics |volume=592 |pages=A80 |doi=10.1051/0004-6361/201628662 |arxiv=1605.08620 |issn=0004-6361|doi-access=free }}</ref> candidate even for an old age of 12 Gyrs ([[age of the universe]] is 13.8 Gyrs)
|none|| 2014<ref>{{cite journal|title=Discovery of a ~250 K Brown Dwarf at 2 pc from the Sun |first=Kevin L. |last=Luhman |date=10 May 2014 |journal=[[Astrophysical Journal Letters]] |volume=786 |issue=2 |page=L18 |doi=10.1088/2041-8205/786/2/L18 |bibcode=2014ApJ...786L..18L |arxiv=1404.6501|s2cid=119102654}}</ref>
|-
| [[2MASS J12074836–3900043]]|| {{sort|15|~15}}<ref>{{Cite journal |last1=Gagné |first1=Jonathan |last2=Gonzales |first2=Eileen C. |last3=Faherty |first3=Jacqueline K. |date=2018 |title=A Gaia DR2 Confirmation that 2MASS J12074836-3900043 is a Member of the TW Hya Association |journal=Research Notes of the American Astronomical Society |volume=2 |issue=2 |page=17 |doi=10.3847/2515-5172/aac0fd |doi-access=free |arxiv=1804.09625|bibcode=2018RNAAS...2...17G }}</ref>|| 7–13 || 200
|L1|| Candidate; distance needed
|[[TW Hydrae association]]<ref>{{Cite journal |last1=Gagné |first1=Jonathan |last2=Gonzales |first2=Eileen C. |last3=Faherty |first3=Jacqueline K. |date=2018-05-01 |title=A Gaia DR2 Confirmation that 2MASS J12074836–3900043 is a Member of the TW HYA Association |journal=Research Notes of the AAS |volume=2 |issue=2 |pages=17 |doi=10.3847/2515-5172/aac0fd |doi-access=free |arxiv=1804.09625 |bibcode=2018RNAAS...2...17G |issn=2515-5172}}</ref>|| 2014<ref>{{cite journal|title=The Coolest Isolated Brown Dwarf Candidate Member of TWA |first=Jonathan |last=Gagné |date=10 April 2014 |journal=[[Astrophysical Journal Letters]] |volume=785 |issue=1 |page=L14 |doi=10.1088/2041-8205/785/1/L14 |bibcode=2014ApJ...785L..14G |arxiv=1403.3120|s2cid=119269921}}</ref>
|-
| [[SIMP J2154–1055]]|| {{sort|10|9–11}} || 30–50 || 63
|L4β|| Age questioned<ref>{{cite journal |title=The Hawaii Infrared Parallax Program. II. Young Ultracool Field Dwarfs |first=Michael C. |last=Liu |date=9 December 2016 |journal=[[Astrophysical Journal]] |volume=833 |issue=1 |page=96 |doi=10.3847/1538-4357/833/1/96 |bibcode=2016ApJ...833...96L|arxiv=1612.02426|s2cid=119192984 |doi-access=free }}</ref>
|[[IC 2391#Argus Association|Argus association]]||2014<ref>{{cite journal|title=SIMP J2154-1055: A New Low-gravity L4β Brown Dwarf Candidate Member of the Argus Association |first=Jonathan |last=Gagné |date=1 September 2014 |journal=[[Astrophysical Journal Letters]] |volume=792 |issue=1 |page=L17 |doi=10.1088/2041-8205/792/1/L17 |bibcode=2014ApJ...792L..17G |arxiv=1407.5344|s2cid=119118880}}</ref>
|-
| [[SDSS J111010.01+011613.1]]|| {{sort|11.28|10.83–11.73}}<ref name="Sanghi et al arxiv" /><ref name="Sanghi et al zenodo" />|| 110–130 || 63
|T5.5|| Confirmed<ref name="Sanghi et al arxiv" />
|AB Doradus moving group|| 2015<ref name=":6">{{cite journal|title=SDSS J111010.01+011613.1: A New Planetary-mass T Dwarf Member of the AB Doradus Moving Group |first=Jonathan |last=Gagné |date=20 July 2015 |journal=[[Astrophysical Journal Letters]] |volume=808 |issue=1 |page=L20 |doi=10.1088/2041-8205/808/1/L20 |bibcode=2015ApJ...808L..20G |arxiv=1506.04195|s2cid=118834638}}</ref>
|-
| [[2MASS J11193254–1137466 AB]]|| {{sort|06|4–8}} || 7–13 || data-sort-value="90" |~90
|L7|| Binary candidate, one of the components has a candidate exomoon or variable atmosphere<ref name=":12" />
|TW Hydrae Association|| 2016<ref>{{cite journal |title=The Nearest Isolated Member of the TW Hydrae Association is a Giant Planet Analog |first=Kendra |last=Kellogg |date=11 April 2016 |journal=[[Astrophysical Journal Letters]] |volume=821 |issue=1 |page=L15 |doi=10.3847/2041-8205/821/1/L15 |bibcode=2016ApJ...821L..15K |arxiv=1603.08529|s2cid=119289711 |doi-access=free }}</ref>
|-
| [[WISEA 1147]]|| {{sort|09|5–13}} || 7–13 || data-sort-value="100" |~100
|L7|| Candidate
|TW Hydrae Association|| 2016<ref name=":16">{{cite journal |title=WISEA J114724.10-204021.3: A Free-floating Planetary Mass Member of the TW Hya Association |first=Adam C. |last=Schneider |date=21 April 2016 |journal=[[Astrophysical Journal Letters]] |volume=822 |issue=1 |page=L1 |doi=10.3847/2041-8205/822/1/L1 |bibcode=2016ApJ...822L...1S |arxiv=1603.07985|s2cid=30068452 |doi-access=free }}</ref>
|-
|[[USco J155150.2-213457]]
|{{sort|09|8–10}}
|6.907-10
|104
|L6
|Candidate, low gravity
|[[Scorpius–Centaurus association|Upper Scorpius association]]
|2016<ref>{{Cite journal |last1=Peña Ramírez |first1=K. |last2=Béjar |first2=V. J. S. |last3=Zapatero Osorio |first3=M. R. |date=2016-02-01 |title=A new free-floating planet in the Upper Scorpius association |url=https://ui.adsabs.harvard.edu/abs/2016A&A...586A.157P |journal=Astronomy and Astrophysics |volume=586 |pages=A157 |doi=10.1051/0004-6361/201527425 |arxiv=1511.05586 |bibcode=2016A&A...586A.157P |s2cid=55940316 |issn=0004-6361}}</ref>
|-
|{{Vanchor|Proplyd 133-353}}
|{{sort|13|<13}}
|0.5–1
|1,344
|M9.5
|Candidate with a [[Photoevaporation|photoevaporating]] disk
|Orion Nebula
|2016<ref name=":24">{{Cite journal |last1=Fang |first1=Min |last2=Kim |first2=Jinyoung Serena |last3=Pascucci |first3=Ilaria |last4=Apai |first4=Dániel |last5=Manara |first5=Carlo Felice |date=2016-12-01 |title=A Candidate Planetary-mass Object with a Photoevaporating Disk in Orion |journal=The Astrophysical Journal Letters |volume=833 |issue=2 |pages=L16 |arxiv=1611.09761 |bibcode=2016ApJ...833L..16F |doi=10.3847/2041-8213/833/2/L16 |issn=0004-637X |doi-access=free }}</ref>
|-
|[[Cha J11110675-7636030]]
|{{sort|04.5|3–6}}
|1–3
|520–550
|M9–L2
|Candidate, but could be surrounded by a disk, which could make it a sub-brown dwarf; other candidates from this work
|Chamaeleon I
|2017<ref name=":5">{{Cite journal |last1=Esplin |first1=T. L. |last2=Luhman |first2=K. L. |last3=Faherty |first3=J. K. |last4=Mamajek |first4=E. E. |last5=Bochanski |first5=J. J. |date=2017-08-01 |title=A Survey for Planetary-mass Brown Dwarfs in the Chamaeleon I Star-forming Region |journal=The Astronomical Journal |volume=154 |issue=2 |pages=46 |doi=10.3847/1538-3881/aa74e2 |arxiv=1706.00058 |bibcode=2017AJ....154...46E |issn=0004-6256 |doi-access=free }}</ref>
|-
|[[PSO J077.1+24]]
|{{sort|06|6}}
|1–2
|470
|L2
|Candidate, work also published another candidate in Taurus
|[[Taurus molecular cloud|Taurus Molecular Cloud]]
|2017<ref>{{Cite journal |last1=Best |first1=William M. J. |last2=Liu |first2=Michael C. |last3=Magnier |first3=Eugene A. |last4=Bowler |first4=Brendan P. |last5=Aller |first5=Kimberly M. |last6=Zhang |first6=Zhoujian |last7=Kotson |first7=Michael C. |last8=Burgett |first8=W. S. |last9=Chambers |first9=K. C. |last10=Draper |first10=P. W. |last11=Flewelling |first11=H. |last12=Hodapp |first12=K. W. |last13=Kaiser |first13=N. |last14=Metcalfe |first14=N. |last15=Wainscoat |first15=R. J. |date=2017-03-01 |title=A Search for L/T Transition Dwarfs with Pan-STARRS1 and WISE. III. Young L Dwarf Discoveries and Proper Motion Catalogs in Taurus and Scorpius-Centaurus |journal=The Astrophysical Journal |volume=837 |issue=1 |pages=95 |doi=10.3847/1538-4357/aa5df0 |arxiv=1702.00789 |bibcode=2017ApJ...837...95B |issn=0004-637X |doi-access=free }}</ref>
|-
|[[2MASS J11151597+1937266|2MASS J1115+1937]]
|{{Val|6|8|4}}
|5–45
|147
|L2γ
|has an accretion disk
|Field, possibly ejected
|2017
|-
|[[Calar 25]]
|{{sort|11.5|11–12}}
|120
|435
|
|Confirmed
|[[Pleiades]]
|2018<ref>{{Cite journal |last1=Zapatero Osorio |first1=M. R. |last2=Béjar |first2=V. J. S. |last3=Lodieu |first3=N. |last4=Manjavacas |first4=E. |date=2018-03-01 |title=Confirming the least massive members of the Pleiades star cluster |journal=Monthly Notices of the Royal Astronomical Society |volume=475 |issue=1 |pages=139–153 |doi=10.1093/mnras/stx3154 |doi-access=free |arxiv=1712.01698 |bibcode=2018MNRAS.475..139Z |issn=0035-8711}}</ref>
|-
|[[2MASS J1324+6358]]
|{{sort|11.25|10.7–11.8}}
|data-sort-value="150" |~150
|data-sort-value="33" |~33
|T2
|unusually red and unlikely binary; robust candidate<ref name="Sanghi et al arxiv" /><ref name="Sanghi et al zenodo" />
|AB Doradus moving group
|2007, 2018<ref>{{Cite journal |last1=Gagné |first1=Jonathan |last2=Allers |first2=Katelyn N. |last3=Theissen |first3=Christopher A. |last4=Faherty |first4=Jacqueline K. |last5=Bardalez Gagliuffi |first5=Daniella |last6=Artigau |first6=Étienne |date=2018-02-01 |title=2MASS J13243553+6358281 Is an Early T-type Planetary-mass Object in the AB Doradus Moving Group |journal=The Astrophysical Journal |volume=854 |issue=2 |pages=L27 |doi=10.3847/2041-8213/aaacfd |arxiv=1802.00493 |bibcode=2018ApJ...854L..27G |issn=0004-637X |doi-access=free }}</ref>
|-
|WISE J0830+2837
|{{sort|08.5|4-13}}
| data-sort-value="1000" |>1,000
|31.3-42.7
|data-sort-value="Y1" |>Y1
|Age uncertain, but old because of high [[Stellar kinematics|velocity]] (high Vtan is indicative of an old [[stellar population]]), Candidate if younger than 10 Gyrs
|none
|2020<ref name=":8">{{Cite journal|last1=Bardalez Gagliuffi |first1=Daniella C. |last2=Faherty |first2=Jacqueline K. |last3=Schneider |first3=Adam C. |last4=Meisner |first4=Aaron |last5=Caselden |first5=Dan |last6=Colin |first6=Guillaume |last7=Goodman |first7=Sam |last8=Kirkpatrick |first8=J. Davy |last9=Kuchner |first9=Marc |last10=Gagné |first10=Jonathan |last11=Logsdon |first11=Sarah E. |date=2020-06-01 |title=WISEA J083011.95+283716.0: A Missing Link Planetary-mass Object |bibcode=2020ApJ...895..145B |journal=The Astrophysical Journal |volume=895 |issue=2 |page=145 |doi=10.3847/1538-4357/ab8d25|arxiv=2004.12829 |s2cid=216553879 |doi-access=free }}</ref>
|-
| [[2MASS J0718-6415]]
| {{sort|03|3 ± 1}}
| 16-28
| 30.5
|T5
| Candidate member of the BPMG. Extremely short rotation period of 1.08 hours, comparable to the [[brown dwarf]] [[2MASS J0348-6022]].<ref name="Vos2022">{{cite journal|arxiv=2201.04711|doi=10.3847/1538-4357/ac4502|title=Let the Great World Spin: Revealing the Stormy, Turbulent Nature of Young Giant Exoplanet Analogs with the Spitzer Space Telescope|year=2022|last1=Vos|first1=Johanna M.|last2=Faherty|first2=Jacqueline K.|last3=Gagné|first3=Jonathan|last4=Marley|first4=Mark|last5=Metchev|first5=Stanimir|last6=Gizis|first6=John|last7=Rice|first7=Emily L.|last8=Cruz|first8=Kelle|journal=The Astrophysical Journal|volume=924|issue=2|page=68|bibcode=2022ApJ...924...68V |s2cid=245904001 |doi-access=free }}</ref><ref>{{cite encyclopedia|url=https://exoplanet.eu/catalog/2mass_j0718_6415--8076/|encyclopedia=[[Extrasolar Planets Encyclopaedia]]|title=The Extrasolar Planet Encyclopaedia – 2MASS J0718-6415|access-date=31 January 2021}}</ref>
|Beta Pictoris moving group
| 2021
|-
|[[DANCe J16081299-2304316]]
|{{sort|04.7|3.1–6.3}}
|3–10
|104
|L6
|One of at least 70 candidates published in this work, spectrum similar to [[HR 8799 c|HR 8799c]]
|Upper Scorpius association
|2021<ref name="Miret-Roig2021" /><ref name=":20">{{Cite journal |last1=Bouy |first1=H. |last2=Tamura |first2=M. |last3=Barrado |first3=D. |last4=Motohara |first4=K. |last5=Castro Rodríguez |first5=N. |last6=Miret-Roig |first6=N. |last7=Konishi |first7=M. |last8=Koyama |first8=S. |last9=Takahashi |first9=H. |last10=Huélamo |first10=N. |last11=Bertin |first11=E. |last12=Olivares |first12=J. |last13=Sarro |first13=L. M. |last14=Berihuete |first14=A. |last15=Cuillandre |first15=J. -C. |date=2022-08-01 |title=Infrared spectroscopy of free-floating planet candidates in Upper Scorpius and Ophiuchus |url=https://ui.adsabs.harvard.edu/abs/2022A&A...664A.111B |journal=Astronomy and Astrophysics |volume=664 |pages=A111 |doi=10.1051/0004-6361/202243850 |arxiv=2206.00916 |bibcode=2022A&A...664A.111B |s2cid=249282287 |issn=0004-6361}}</ref>
|-
|[[WISE J2255−3118]]
|{{sort|02.37|2.15–2.59}}
|24
|data-sort-value="45" |~45
|T8
|very red, candidate<ref name="Sanghi et al arxiv" /><ref name="Sanghi et al zenodo" />
|Beta Pictoris moving group
|2011,2021<ref name=":2">{{Cite journal |last1=Zhang |first1=Zhoujian |last2=Liu |first2=Michael C. |last3=Best |first3=William M. J. |last4=Dupuy |first4=Trent J. |last5=Siverd |first5=Robert J. |date=2021-04-01 |title=The Hawaii Infrared Parallax Program. V. New T-dwarf Members and Candidate Members of Nearby Young Moving Groups |journal=The Astrophysical Journal |volume=911 |issue=1 |pages=7 |doi=10.3847/1538-4357/abe3fa |arxiv=2102.05045 |bibcode=2021ApJ...911....7Z |issn=0004-637X |doi-access=free }}</ref>
|-
|[[WISE J024124.73-365328.0]]
|{{sort|04.97|4.64–5.30}}
|45
|data-sort-value="61" |~61
|T7
|candidate<ref name="Sanghi et al arxiv" /><ref name="Sanghi et al zenodo" />
|Argus association
|2012, 2021<ref name=":2" />
|-
|[[2MASS J0013−1143]]
|{{sort|07.77|7.29–8.25}}
|45
|data-sort-value="82" |~82
|T4
|binary candidate or composite atmosphere, candidate<ref name="Sanghi et al arxiv" /><ref name="Sanghi et al zenodo" />
|Argus association
|2017, 2021<ref name=":2" />
|-
|[[SDSS J020742.48+000056.2]]
|{{sort|07.86|7.11–8.61}}
|45
|data-sort-value="112" |~112
|T4.5
|candidate<ref name="Sanghi et al arxiv" /><ref name="Sanghi et al zenodo" />
|Argus association
|2002, 2021<ref name=":2" />
|-
|[[2MASSI J0453264-175154]]
|{{sort|12.83|12.68–12.98}}
|24
|data-sort-value="99" |~99
|L2.5β
|low gravity, candidate<ref name="Sanghi et al arxiv" /><ref name="Sanghi et al zenodo" />
|Beta Pictoris moving group
|2003, 2023<ref name="Sanghi et al arxiv" /><ref name="Sanghi et al zenodo" />
|-
|[[CWISE J0506+0738]]
|{{sort|07|7 ± 2}}
|22
|104
|L8γ–T0γ
|Candidate member of the BPMG. Extreme red near-infrared colors.<ref>{{Cite journal |last1=Schneider |first1=Adam C. |last2=Burgasser |first2=Adam J. |last3=Bruursema |first3=Justice |last4=Munn |first4=Jeffrey A. |last5=Vrba |first5=Frederick J. |last6=Caselden |first6=Dan |last7=Kabatnik |first7=Martin |last8=Rothermich |first8=Austin |last9=Sainio |first9=Arttu |last10=Bickle |first10=Thomas P. |last11=Dahm |first11=Scott E. |last12=Meisner |first12=Aaron M. |last13=Kirkpatrick |first13=J. Davy |last14=Suárez |first14=Genaro |last15=Gagné |first15=Jonathan |date=2023-02-01 |title=Redder than Red: Discovery of an Exceptionally Red L/T Transition Dwarf |journal=The Astrophysical Journal |volume=943 |issue=2 |pages=L16 |doi=10.3847/2041-8213/acb0cd |arxiv=2301.02322 |bibcode=2023ApJ...943L..16S |s2cid=255522681 |issn=0004-637X |doi-access=free }}</ref>
|Beta Pictoris moving group
|2023
|}

=== Discovered via microlensing ===
These objects were discovered via [[Gravitational microlensing|microlensing]]. Rogue planets discovered via microlensing can only be studied by the lensing event and are often also consistent with exoplanets in a wide orbit around an unseen star.<ref name=":3">{{citation |last1=Mróz |first1=Przemek |title=A terrestrial-mass rogue planet candidate detected in the shortest-timescale microlensing event |journal=The Astrophysical Journal |volume=903 |issue=1 |pages=L11 |year=2020 |arxiv=2009.12377 |bibcode=2020ApJ...903L..11M |doi=10.3847/2041-8213/abbfad |s2cid=221971000 |display-authors=29 |last2=Poleski |first2=Radosław |last3=Gould |first3=Andrew |last4=Udalski |first4=Andrzej |last5=Sumi |first5=Takahiro |last6=Szymański |first6=Michał K. |last7=Soszyński |first7=Igor |last8=Pietrukowicz |first8=Paweł |last9=Kozłowski |first9=Szymon |last10=Skowron |first10=Jan |last11=Ulaczyk |first11=Krzysztof |last12=Albrow |first12=Michael D. |last13=Chung |first13=Sun-Ju |last14=Han |first14=Cheongho |last15=Hwang |first15=Kyu-Ha |last16=Jung |first16=Youn Kil |last17=Kim |first17=Hyoun-Woo |last18=Ryu |first18=Yoon-Hyun |last19=Shin |first19=In-Gu |last20=Shvartzvald |first20=Yossi |last21=Yee |first21=Jennifer C. |last22=Zang |first22=Weicheng |last23=Cha |first23=Sang-Mok |last24=Kim |first24=Dong-Jin |last25=Kim |first25=Seung-Lee |last26=Lee |first26=Chung-Uk |last27=Lee |first27=Dong-Joo |last28=Lee |first28=Yongseok |last29=Park |first29=Byeong-Gon |last30=Pogge |first30=Richard W. |doi-access=free }}</ref>
{| class="wikitable sortable" style="margin:1em auto; text-align: center;"
! [[Exoplanet]]
! [[Planetary mass|Mass]] ({{Jupiter mass|link=y}})
!Mass ({{Earth mass|link=true}})
! data-sort-type="number" | Distance (ly)
! Status
! Discovery
|-
|[[OGLE-2012-BLG-1323]]
|0.0072–0.072
|2.3–23
|
|candidate; distance needed
|2017<ref>{{Cite journal |last1=Mróz |first1=Przemek |last2=Udalski |first2=Andrzej |last3=Bennett |first3=David P. |last4=Ryu |first4=Yoon-Hyun |last5=Sumi |first5=Takahiro |last6=Shvartzvald |first6=Yossi |last7=Skowron |first7=Jan |last8=Poleski |first8=Radosław |last9=Pietrukowicz |first9=Paweł |last10=Kozłowski |first10=Szymon |last11=Szymański |first11=Michał K. |last12=Wyrzykowski |first12=Łukasz |last13=Soszyński |first13=Igor |last14=Ulaczyk |first14=Krzysztof |last15=Rybicki |first15=Krzysztof |date=2019-02-01 |title=Two new free-floating or wide-orbit planets from microlensing |journal=Astronomy and Astrophysics |volume=622 |pages=A201 |doi=10.1051/0004-6361/201834557 |bibcode=2019A&A...622A.201M |issn=0004-6361|doi-access=free |arxiv=1811.00441 }}</ref><ref name="Becky Ferreira">{{cite web |author=Becky Ferreira |date=9 November 2018 |title=Rare Sighting of Two Rogue Planets That Do Not Orbit Stars |url=https://motherboard.vice.com/en_us/article/ev3dkj/rare-sighting-of-two-rogue-planets-that-do-not-orbit-stars |access-date=10 February 2019 |publisher=Motherboard}}</ref><ref name="Jake Parks">{{cite web |author=Jake Parks |date=16 November 2018 |title=These Two New 'Rogue Planets' Wander the Cosmos Without Stars |url=http://blogs.discovermagazine.com/d-brief/2018/11/16/rogue-planets-discovered/#.XEeAI2l7mUk |access-date=10 February 2019 |publisher=Discover Magazine |archive-date=16 November 2018 |archive-url=https://web.archive.org/web/20181116233740/http://blogs.discovermagazine.com/d-brief/2018/11/16/rogue-planets-discovered/#.XEeAI2l7mUk |url-status=dead }}</ref><ref name="astronomy.com">{{cite web |author=Jake Parks |date=15 November 2018 |title=Two free-range planets found roaming the Milky Way in solitude |url=http://www.astronomy.com/news/2018/11/rogue-one-and-two |access-date=10 February 2019 |publisher=Astronomy Magazine}}</ref>
|-
|[[OGLE-2017-BLG-0560]]
|1.9–20
|604–3,256
|
|candidate; distance needed
|2017<ref name="Becky Ferreira" /><ref name="Jake Parks" /><ref name="astronomy.com" />
|-
|MOA-2015-BLG-337L
|9.85
|3,130
|23,156
|may be a binary [[brown dwarf]] instead
|2018<ref>{{Cite web |title=Exoplanet-catalog |url=https://exoplanets.nasa.gov/exoplanet-catalog/6413/moa-2015-blg-337l-b/ |access-date=2021-01-04 |website=Exoplanet Exploration: Planets Beyond our Solar System}}</ref><ref>{{Cite journal |last1=Miyazaki |first1=S. |last2=Sumi |first2=T. |last3=Bennett |first3=D. P. |last4=Gould |first4=A. |last5=Udalski |first5=A. |last6=Bond |first6=I. A. |last7=Koshimoto |first7=N. |last8=Nagakane |first8=M. |last9=Rattenbury |first9=N. |last10=Abe |first10=F. |last11=Bhattacharya |first11=A. |last12=Barry |first12=R. |last13=Donachie |first13=M. |last14=Fukui |first14=A. |last15=Hirao |first15=Y. |date=2018-09-01 |title=MOA-2015-BLG-337: A Planetary System with a Low-mass Brown Dwarf/Planetary Boundary Host, or a Brown Dwarf Binary |journal=The Astronomical Journal |volume=156 |issue=3 |pages=136 |doi=10.3847/1538-3881/aad5ee |doi-access=free |arxiv=1804.00830 |bibcode=2018AJ....156..136M |issn=0004-6256}}</ref>
|-
|[[KMT-2019-BLG-2073]]
|0.19
|59
|
|candidate; distance needed
|2020<ref>{{cite journal |last1=Kim |first1=Hyoun-Woo |last2=Hwang |first2=Kyu-Ha |last3=Gould |first3=Andrew |last4=Yee |first4=Jennifer C. |last5=Ryu |first5=Yoon-Hyun |last6=Albrow |first6=Michael D. |last7=Chung |first7=Sun-Ju |last8=Han |first8=Cheongho |last9=Jung |first9=Youn Kil |last10=Lee |first10=Chung-Uk |last11=Shin |first11=In-Gu |last12=Shvartzvald |first12=Yossi |last13=Zang |first13=Weicheng |last14=Cha |first14=Sang-Mok |last15=Kim |first15=Dong-Jin |year=2021 |title=KMT-2019-BLG-2073: Fourth Free-floating Planet Candidate with θ e < 10 μas |journal=The Astronomical Journal |volume=162 |issue=1 |page=15 |arxiv=2007.06870 |bibcode=2021AJ....162...15K |doi=10.3847/1538-3881/abfc4a |s2cid=235445277 |last16=Kim |first16=Seung-Lee |last17=Lee |first17=Dong-Joo |last18=Lee |first18=Yongseok |last19=Park |first19=Byeong-Gon |last20=Pogge |first20=Richard W. |doi-access=free }}</ref>
|-
|OGLE-2016-BLG-1928
|0.001-0.006
|0.3–2
|30,000–180,000
|candidate
|2020<ref name=":3" />
|-
|OGLE-2019-BLG-0551
|0.0242-0.3
|7.69–95
|
|Poorly characterized<ref name=":0">{{citation |last1=Mróz |first1=Przemek |title=A Free-floating or Wide-orbit Planet in the Microlensing Event OGLE-2019-BLG-0551 |journal=The Astronomical Journal |volume=159 |issue=6 |page=262 |year=2020 |arxiv=2003.01126 |bibcode=2020AJ....159..262M |doi=10.3847/1538-3881/ab8aeb |s2cid=211817861 |display-authors=1 |last2=Poleski |first2=Radosław |last3=Han |first3=Cheongho |last4=Udalski |first4=Andrzej |last5=Gould |first5=Andrew |last6=Szymański |first6=Michał K. |last7=Soszyński |first7=Igor |last8=Pietrukowicz |first8=Paweł |last9=Kozłowski |first9=Szymon |last10=Skowron |first10=Jan |last11=Ulaczyk |first11=Krzysztof |last12=Gromadzki |first12=Mariusz |last13=Rybicki |first13=Krzysztof |last14=Iwanek |first14=Patryk |last15=Wrona |first15=Marcin |last16=Albrow |first16=Michael D. |last17=Chung |first17=Sun-Ju |last18=Hwang |first18=Kyu-Ha |last19=Ryu |first19=Yoon-Hyun |last20=Jung |first20=Youn Kil |last21=Shin |first21=In-Gu |last22=Shvartzvald |first22=Yossi |last23=Yee |first23=Jennifer C. |last24=Zang |first24=Weicheng |last25=Cha |first25=Sang-Mok |last26=Kim |first26=Dong-Jin |last27=Kim |first27=Hyoun-Woo |last28=Kim |first28=Seung-Lee |last29=Lee |first29=Chung-Uk |last30=Lee |first30=Dong-Joo |doi-access=free }}</ref>
|2020<ref name=":0" />
|-
|[[VVV-2012-BLG-0472L]]
|data-sort-value="31" |10.5
|3,337
|3,200
|
|2022<ref>{{Cite journal |last1=Kaczmarek |first1=Zofia |last2=McGill |first2=Peter |last3=Evans |first3=N. Wyn |last4=Smith |first4=Leigh C. |last5=Wyrzykowski |first5=Łukasz |last6=Howil |first6=Kornel |last7=Jabłońska |first7=Maja |date=2022-08-01 |title=Dark lenses through the dust: parallax microlensing events in the VVV |journal=Monthly Notices of the Royal Astronomical Society |volume=514 |issue=4 |pages=4845–4860 |doi=10.1093/mnras/stac1507 |doi-access=free |arxiv=2205.07922 |bibcode=2022MNRAS.514.4845K |issn=0035-8711}}</ref>
|-
|[[MOA-9y-770L]]
|0.07
|{{Val|22.3|42.2|17.4}}
|22,700
|
|2023<ref name=":1">{{Cite journal |arxiv=2303.08279 |first1=Naoki |last1=Koshimoto |first2=Takahiro |last2=Sumi |title=Terrestrial and Neptune mass free-floating planet candidates from the MOA-II 9-year Galactic Bulge survey |date=2023-03-14 |last3=Bennett |first3=David P. |last4=Bozza |first4=Valerio |last5=Mróz |first5=Przemek |last6=Udalski |first6=Andrzej |last7=Rattenbury |first7=Nicholas J. |last8=Abe |first8=Fumio |last9=Barry |first9=Richard |last10=Bhattacharya |first10=Aparna |last11=Bond |first11=Ian A. |last12=Fujii |first12=Hirosane |last13=Fukui |first13=Akihiko |last14=Hamada |first14=Ryusei |last15=Hirao |first15=Yuki|journal=The Astronomical Journal |volume=166 |issue=3 |page=107 |doi=10.3847/1538-3881/ace689 |bibcode=2023AJ....166..107K |doi-access=free }}</ref>
|-
|[[MOA-9y-5919L]]
|0.0012 or 0.0024
|{{Val|0.37|1.11|0.27}} or {{Val|0.75|1.23|0.46}}
|14,700 or 19,300
|
|2023<ref name=":1" />
|}

=== Discovered via transit ===
{| class="wikitable sortable" style="margin:1em auto; text-align: center;"
! [[Exoplanet]]
! [[Planetary mass|Mass]]
({{Jupiter mass|link=y}})
! data-sort-type="number" | Age
(Myr)
! Distance
(ly)
! [[Stellar classification|Spectral type]]
!Status
![[Stellar association|Stellar assoc.]] membership
!Discovery
|-
|[[J1407b]]
|{{sort|06|<6}}
|
|<451
|
|Candidate [[Atacama Large Millimeter Array|ALMA]] detection; although the object's brightness and proximity is consistent with it being the same object that eclipsed the star [[V1400 Centauri]] in 2007, follow-up observations by ALMA are needed to confirm whether it is moving, let alone in the right direction.<ref name="Kenworthy2020">{{cite journal |last1=Kenworthy |first1=M. A. |last2=Klaassen |first2=P. D. |display-authors=etal |date=January 2020 |title=ALMA and NACO observations towards the young exoring transit system J1407 (V1400 Cen) |journal=[[Astronomy & Astrophysics]] |volume=633 |issue= |pages=A115 |arxiv=1912.03314 |bibcode=2020A&A...633A.115K |doi=10.1051/0004-6361/201936141}}</ref>
|none
|2012, 2020<ref name="Kenworthy2020" />
|}

== See also ==
* {{annotated link|Intergalactic star}}
* [[Interstellar object]] – an astronomical object in interstellar space that is not gravitationally bound to a star
* [[ʻOumuamua]] – an [[interstellar object]] that passed through the Solar System in 2017
* [[Rogue black hole]] – a gravitationally unbound black hole
* [[Extragalactic planet#Evidence of a population of rogue planets|Rogue extragalactic planets]] – rogue planets outside the Milky Way galaxy
* [[Tidally detached exomoon]] – rogue planets that were originally moons

=== In fiction ===
* ''[[A Pail of Air]]'' (1951) — a science fiction short story [[Fritz Leiber]]
* ''[[Remina]]'' (2004–2005) – horror manga by [[Junji Ito]]
* ''[[Melancholia (2011 film)|Melancholia]]'' (2011) – science fiction film by [[Lars von Trier]]
* ''[[Dark Eden (novel)|Dark Eden]]'' (2012) – a [[social science fiction]] novel by [[Chris Beckett]]
* ''[[The Wandering Earth]]'' (2019) – a science fiction film directed by [[Frant Gwo]]
* ''[[Gemini Home Entertainment]]'' (2019–present) – horror anthology web series by Remy Abode
* ''[[Carol & the End of the World]]'' (2023) – an animated adult comedy miniseries by [[Dan Guterman]]

== References ==
{{Reflist|30em}}

== Bibliography ==
* [https://web.archive.org/web/20140529085818/http://mh-gps-p1.caltech.edu/uploads/File/People/djs/interstellar_planets.pdf "Possibility of Life Sustaining Planets in Interstellar Space"] Article by Stevenson similar to the ''Nature'' article but with more information.

== External links ==
{{Wiktionary|Interstellar planet}}
{{Commons category|Free-floating planets}}
* [https://www.iau.org/static/resolutions/Resolution_GA26-5-6.pdf Definition of a "Planet"] (Resolution B5 – [[IAU]])
* [http://www.space.com/scienceastronomy/060605_planemos.html Strange New Worlds Could Make Miniature Solar Systems] Robert Roy Britt (SPACE.com) 5 June 2006 11:35 am ET
* [https://web.archive.org/web/20060820075858/http://www.iau2006.org/mirror/www.iau.org/iau0601/iau0601_release.html The IAU draft definition of "planet" and "plutons"] press release ([[International Astronomical Union]]) 2006

{{exoplanet}}
{{Portal bar|Astronomy|Stars|Outer space}}

[[Category:Articles containing video clips]]
[[Category:Planetary-mass objects]]
[[Category:Rogue planets| ]]
[[Category:Space hazards]]
[[Category:Types of planet]]