Rogue planet
Template:About Template:Short description Template:Use dmy dates
A rogue planet, also termed a free-floating planet (FFP) or an isolated planetary-mass object (iPMO), is an interstellar object of planetary mass which is not gravitationally bound to any star or brown dwarf.<ref name="shostak">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="lloyd">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name=":4">Template:Cite journal</ref>
Rogue planets may originate from 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 is expected to refine.<ref>Neil deGrasse Tyson in Cosmos: A Spacetime Odyssey as referred to by 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 dwarfs.<ref>Working Group on Extrasolar Planets – Definition of a "Planet" Position Statement on the Definition of a "Planet" (IAU) Template:Webarchive</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">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
TerminologyEdit
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">Template:Cite journal</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>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> wandering planet<ref name=":19" /> and free-floating planet<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> in different press releases.
DiscoveryEdit
Isolated planetary-mass objects (iPMO) were first discovered in 2000 by the UK team Lucas & Roche with UKIRT in the Orion Nebula.<ref name=":14">Template:Cite journal</ref> In the same year the Spanish team Zapatero Osorio et al. discovered iPMOs with Keck spectroscopy in the σ Orionis cluster.<ref name=":10" /> The spectroscopy of the objects in the Orion Nebula was published in 2001.<ref name=":11" /> Both European teams are now recognized for their quasi-simultaneous discoveries.<ref name=":7" /> In 1999 the Japanese team Oasa et al. discovered objects in Chamaeleon I<ref>Template:Cite journal</ref> that were spectroscopically confirmed years later in 2004 by the US team Luhman et al.<ref>Template:Cite journal</ref>
ObservationEdit
There are two techniques to discover free-floating planets: direct imaging and microlensing.
MicrolensingEdit
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 Template:Convert MOA-II telescope at New Zealand's Mount John Observatory and the Template:Convert 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>Homeless' Planets May Be Common in Our Galaxy Template:Webarchive by Jon Cartwright, Science Now, 18 May 2011, Accessed 20 May 2011</ref><ref>Planets that have no stars: New class of planets discovered, Physorg.com, 18 May 2011. Accessed May 2011.</ref><ref>Template:Cite journal</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>{{#invoke:citation/CS1|citation |CitationClass=web }}</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>Template:Cite journal</ref>
In September 2020, astronomers using microlensing techniques reported the detection, for the first time, of an Earth-mass rogue planet (named OGLE-2016-BLG-1928) unbound to any star and free floating in the Milky Way galaxy.<ref name="Mróz2020">Template:Cite journal</ref><ref name="UT-20201001">Template:Cite news</ref><ref name="SA-20201019a">Template:Cite news</ref>
Direct imagingEdit
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 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>Template:Cite journal</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-forming regions of which astronomers know their age. These objects are younger than 200 Myrs, are massive (>5 Template:Jupiter mass)<ref name=":4" /> and belong to the L- and T-dwarfs.<ref name=":5" /><ref name=":6" /> There is however a small growing sample of cold and old Y-dwarfs that have estimated masses of 8-20 Template:Jupiter mass.<ref>Template:Cite journal</ref> Nearby rogue planet candidates of spectral type Y include WISE 0855−0714 at a distance of Template:Val.<ref name="Luhman2016">Template:Cite journal</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 kinematically different from their natal star-forming region, should not be surrounded by a circumstellar disk and have high metallicity.<ref name=":7">Template:Cite journal</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 Vtan of about 100 km/s, which is high, but still consistent with formation in our galaxy. For WISE 1534–1043<ref>Template:Cite journal</ref> one alternative scenario explains this object as an ejected exoplanet due to its high Vtan 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 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">Template:Cite journal</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" />
BinariesEdit
Template:Multiple image The first discovery of a resolved planetary-mass binary was 2MASS J1119–1137AB. There are however other binaries known, such as 2MASS J1553022+153236AB,<ref>Template:Cite journal</ref><ref name=":26">Template:Cite journal</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>Template:Cite journal</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. The discovery was surprising for two reasons: the trend of 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 AU.<ref name=":21"/> It is unclear how these JuMBOs formed, but an extensive study argued that they formed in situ, like stars.<ref>Template:Cite journal</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">Template:Cite arXiv</ref> Kevin Luhman reanalysed the NIRCam data and found that most JuMBOs did not appear in his sample of substellar objects. Moreover the color was consistent with reddened background sources or low signal-to-noise sources. He considers only JuMBO 29 as a good candidate for a binary planetary-mass system.<ref name="Luhman2024">Template:Cite journal</ref>
Total number of known iPMOsEdit
There are likely hundreds<ref name="Miret-Roig2021" /><ref name=":21" /> of known candidate iPMOs, over a hundred<ref>Template:Cite book</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 and Ophiuchus with masses between 4 and 13 Template:Jupiter mass 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 dynamical instabilities.<ref name="Miret-Roig2021">Template:Cite journal See also Nature SharedIt article link; ESO article link</ref><ref name="eso2120">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name=":19">{{#invoke:citation/CS1|citation |CitationClass=web }}</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 Template: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 Template:Jupiter mass. A surprising number of these objects formed wide binaries, which was not predicted.<ref name=":21" />
FormationEdit
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 starEdit
{{#invoke:Labelled list hatnote|labelledList|Main article|Main articles|Main page|Main pages}} Objects with a mass of at least one Jupiter mass were thought to be able to form via collapse and fragmentation of molecular clouds from models in 2001.<ref>Template:Cite journal</ref> Pre-JWST observations have shown that objects below 3-5 Template: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 Template:Jupiter mass might form on their own, not requiring a steep cut-off mass.<ref name=":21" /> A particular type of globule, called globulettes, are thought to be birthplaces for brown dwarfs and planetary-mass objects. Globulettes are found in the Rosette Nebula and IC 1805.<ref>Template:Cite journal</ref> Sometimes young iPMOs are still surrounded by a disk that could form 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 transiting.<ref name=":12">Template:Cite journal</ref>
DisksEdit
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. Most well known is the iPMO OTS 44 discovered to have a disk and being located in Chamaeleon I. Chamaeleon I and II have other candidate iPMOs with disks.<ref>Template:Cite journal</ref><ref name=":22">Template:Cite journal</ref><ref name=":5" /> Other star-forming regions with iPMOs with disks or accretion are Lupus I,<ref name=":22" /> Rho Ophiuchi Cloud Complex,<ref name=":23">Template:Cite journal</ref> Sigma Orionis cluster,<ref>Template:Cite journal</ref> Orion Nebula,<ref name=":24" /> Taurus,<ref name=":23" /><ref>Template:Cite journal</ref> NGC 1333<ref>Template:Cite journal</ref> and IC 348.<ref>Template:Cite journal</ref> A large survey of disks around brown dwarfs and iPMOs with ALMA found that these disks are not massive enough to form earth-mass planets. There is still the possibility that the disks already have formed planets.<ref name=":23" /> Studies of red dwarfs have shown that some have gas-rich disks at a relative old age. These disks were dubbed 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 Template:Jupiter mass, which is close to the planetary-mass regime.<ref>Template:Cite journal</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">Template:Cite journal</ref> In May 2025 researchers using JWST found that the disk around Cha 1107−7626 contains hydrocarbons. Cha 1107−7626 (6-10 Template:Jupiter mass) is one of the lowest-mass objects with a dusty disk.<ref>Template:Cite arXiv</ref>
Formation like a planetEdit
Ejected planets are predicted to be mostly low-mass (<30 Template:Earth mass Figure 1 Ma et al.)<ref name=":13">Template:Cite journal</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 Template:Solar mass stars eject a total of 16.8 Template:Earth mass per star with a typical (median) mass of 0.8 Template:Earth mass for an individual free-floating planet (FFP). For lower mass red dwarfs with a mass of 0.3 Template:Solar mass 12% of stars eject a total of 5.1 Template:Earth mass per star with a typical mass of 0.3 Template:Earth mass for an individual FFP.
Hong et al.<ref>Template:Cite journal</ref> predicted that exomoons can be scattered by planet-planet interactions and become ejected exomoons. Higher mass (0.3-1 Template: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">Template:Cite journal</ref> Another suggested scenario is the ejection of planets in a tilted 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>Template:Cite journal</ref><ref>Template:Cite journal</ref> Although the effectiveness of this mechanism depends on the encounter geometry, which is not well constrained yet both observationally and theoretically
Formation via encounters between young circumstellar disksEdit
Encounters between young circumstellar disks, which are marginally gravitationally stable, can produce elongated tidal bridges that collapse locally to form iPMOs.<ref>Template:Cite news</ref> These iPMOs host expansive disks similar to observations,<ref name=":24" /> which the ejected planet hyperthesis can hardly explain. They also have a high multiplicity fraction in their formation, as suggested by iPMOs in the Trapezium cluster.<ref name=":21" /> Although the effectiveness of this mechanism depends on the encounter geometry, which is not well constrained yet both observationally and theoretically.<ref>Template:Cite journal</ref>
Other scenariosEdit
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-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 form from a combination of scenarios.<ref name=":25" />
FateEdit
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 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>Template:Cite journal</ref>
WarmthEdit
Interstellar planets generate little heat and are not heated by a star.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</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">Template:Cite journal</ref>
During planetary-system formation, several small protoplanetary bodies may be ejected from the system.<ref>Template:Cite journal</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 magnetospheres and sea floor volcanism, hydrothermal vents 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 thermal emissions may be detectable from an object that is less than 1,000 astronomical units from Earth.<ref>Template:Cite journal</ref> Around five percent of Earth-sized ejected planets with Moon-sized natural satellites would retain their satellites after ejection. A large satellite would be a source of significant geological tidal heating.<ref>Template:Cite journal</ref>
ListEdit
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 dwarfs. 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 imagingEdit
These objects were discovered with the direct imaging method. Many were discovered in young star-clusters or stellar associations and a few old are known (such as WISE 0855−0714). List is sorted after discovery year.
| Exoplanet | Mass | Age
(Myr) |
Distance
(ly) |
Spectral type | Status | Stellar assoc. membership | Discovery | |
|---|---|---|---|---|---|---|---|---|
| OTS 44 | Template:Sort | 0.5–3 | 554 | M9.5 | Likely a low-mass brown dwarf<ref name=":9">Template:Cite journal</ref> | Chamaeleon I | 1998 | |
| S Ori 52 | Template:Sort | 1–5 | 1,150 | Age and mass uncertain; may be a foreground brown dwarf | σ Orionis cluster | 2000<ref name=":10">Template:Cite journal</ref> | ||
| Proplyd 061-401 | Template:Sort | 1 | 1,344 | L4–L5 | Candidate, 15 candidates in total from this work | Orion nebula | 2001<ref name=":11">Template:Cite journal</ref> | |
| S Ori 70 | Template:Sort | 3 | 1150 | T6 | interloper?<ref name=":7" /> | σ Orionis cluster | 2002 | |
| Cha 110913-773444 | Template:Sort | 2~ | 529 | >M9.5 | Confirmed | Chamaeleon I | 2004<ref>Template:Cite journal</ref> | |
| SIMP J013656.5+093347 | Template:Sort | 200~ | 20-22 | T2.5 | Candidate | Carina-Near moving group | 2006<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> | |
| UGPS J072227.51−054031.2 | Template:Sort<ref name="Sanghi et al arxiv" /><ref name="Sanghi et al zenodo" /> | 1000 – 5000 | 13 | T9 | Mass uncertain | none | 2010 | |
| M10-4450 | Template:Sort | 1 | 325 | T | Candidate | rho Ophiuchi cloud | 2010<ref>Template:Cite journal</ref> | |
| WISE 1828+2650 | Template:Nowrap | Template:Nowrap | 47 | >Y2 | candidate, could be binary | none | 2011 | |
| CFBDSIR 2149−0403 | Template:Sort | 110–130 | 117–143 | T7 | Candidate | AB Doradus moving group | 2012<ref>Template:Cite journal</ref> | |
| SONYC-NGC1333-36 | Template:Sort | 1 | 978 | L3 | candidate, NGC 1333 has two other objects with masses below 15 Template:Jupiter mass | NGC 1333 | 2012<ref>Template:Cite journal</ref> | |
| SSTc2d J183037.2+011837 | Template:Sort | 3 | 848–1354 | T? | Candidate, also called ID 4 | Serpens Core cluster<ref>{{#invoke:citation/CS1|citation | CitationClass=web
}}</ref> (in the Serpens Cloud) |
2012<ref name=":15">Template:Cite journal</ref> |
| PSO J318.5−22 | Template:Sort<ref name="Sanghi et al arxiv">Template:Cite arXiv</ref><ref name="Sanghi et al zenodo">Template:Cite journal</ref> | 21–27 | 72.32 | L7 | Confirmed; also known as 2MASS J21140802-2251358 | Beta Pictoris Moving group | 2013<ref name=":17">Template:Cite journal</ref><ref>Template:Cite journal</ref> | |
| 2MASS J2208+2921 | Template:Sort | 21–27 | 115 | L3γ | Candidate; radial velocity needed | Beta Pictoris Moving group | 2014<ref>Template:Cite journal</ref> | |
| WISE J1741-4642 | Template:Sort | 23–130 | L7pec | Candidate | Beta Pictoris or AB Doradus moving group | 2014<ref>Template:Cite journal</ref> | ||
| WISE 0855−0714 | Template:Sort | >1,000 | 7.1 | Y4 | Age uncertain, but old due to solar vicinity object;<ref>Template:Cite journal</ref> candidate even for an old age of 12 Gyrs (age of the universe is 13.8 Gyrs) | none | 2014<ref>Template:Cite journal</ref> | |
| 2MASS J12074836–3900043 | Template:Sort<ref>Template:Cite journal</ref> | 7–13 | 200 | L1 | Candidate; distance needed | TW Hydrae association<ref>Template:Cite journal</ref> | 2014<ref>Template:Cite journal</ref> | |
| SIMP J2154–1055 | Template:Sort | 30–50 | 63 | L4β | Age questioned<ref>Template:Cite journal</ref> | Argus association | 2014<ref>Template:Cite journal</ref> | |
| SDSS J111010.01+011613.1 | Template:Sort<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">Template:Cite journal</ref> | |
| 2MASS J11193254–1137466 AB | Template:Sort | 7–13 | ~90 | L7 | Binary candidate, one of the components has a candidate exomoon or variable atmosphere<ref name=":12" /> | TW Hydrae Association | 2016<ref>Template:Cite journal</ref> | |
| WISEA 1147 | Template:Sort | 7–13 | ~100 | L7 | Candidate | TW Hydrae Association | 2016<ref name=":16">Template:Cite journal</ref> | |
| USco J155150.2-213457 | Template:Sort | 6.907-10 | 104 | L6 | Candidate, low gravity | Upper Scorpius association | 2016<ref>Template:Cite journal</ref> | |
| Proplyd 133-353 | Template:Sort | 0.5–1 | 1,344 | M9.5 | Candidate with a photoevaporating disk | Orion Nebula | 2016<ref name=":24">Template:Cite journal</ref> | |
| Cha J11110675-7636030 | Template:Sort | 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">Template:Cite journal</ref> | |
| PSO J077.1+24 | Template:Sort | 1–2 | 470 | L2 | Candidate, work also published another candidate in Taurus | Taurus Molecular Cloud | 2017<ref>Template:Cite journal</ref> | |
| 2MASS J1115+1937 | Template:Val | 5–45 | 147 | L2γ | has an accretion disk | Field, possibly ejected | 2017 | |
| Calar 25 | Template:Sort | 120 | 435 | Confirmed | Pleiades | 2018<ref>Template:Cite journal</ref> | ||
| 2MASS J1324+6358 | Template:Sort | ~150 | ~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>Template:Cite journal</ref> | |
| WISE J0830+2837 | Template:Sort | >1,000 | 31.3-42.7 | >Y1 | Age uncertain, but old because of high velocity (high Vtan is indicative of an old stellar population), Candidate if younger than 10 Gyrs | none | 2020<ref name=":8">Template:Cite journal</ref> | |
| 2MASS J0718-6415 | Template:Sort | 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">Template:Cite journal</ref><ref>Template:Cite encyclopedia</ref> | Beta Pictoris moving group | 2021 | |
| DANCe J16081299-2304316 | Template:Sort | 3–10 | 104 | L6 | One of at least 70 candidates published in this work, spectrum similar to HR 8799c | Upper Scorpius association | 2021<ref name="Miret-Roig2021" /><ref name=":20">Template:Cite journal</ref> | |
| WISE J2255−3118 | Template:Sort | 24 | ~45 | T8 | very red, candidate<ref name="Sanghi et al arxiv" /><ref name="Sanghi et al zenodo" /> confirmed?<ref>Template:Cite journal</ref> | Beta Pictoris moving group | 2011,2021<ref name=":2">Template:Cite journal</ref> | |
| WISE J024124.73-365328.0 | Template:Sort | 45 | ~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 | Template:Sort | 45 | ~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 | Template:Sort | 45 | ~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 | Template:Sort | 24 | ~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 | Template:Sort | 22 | 104 | L8γ–T0γ | Candidate member of the BPMG. Extreme red near-infrared colors.<ref>Template:Cite journal</ref> | Beta Pictoris moving group | 2023 |
Discovered via microlensingEdit
These objects were discovered via microlensing. Rogue planets discovered via microlensing can only be studied by the lensing event. Some of them could also be exoplanets in a wide orbit around an unseen star.<ref name=":3">Template:Citation</ref>
| Exoplanet | Mass (Template:Jupiter mass) | Mass (Template:Earth mass) | Distance (ly) | Status | Discovery | |||
|---|---|---|---|---|---|---|---|---|
| OGLE-2012-BLG-1323 | 0.0072–0.072 | 2.3–23 | candidate; distance needed | 2017<ref>Template:Cite journal</ref><ref name="Becky Ferreira">{{#invoke:citation/CS1|citation | CitationClass=web
}}</ref><ref name="Jake Parks">{{#invoke:citation/CS1|citation |
CitationClass=web
}}</ref><ref name="astronomy.com">{{#invoke:citation/CS1|citation |
CitationClass=web
}}</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 | citation | CitationClass=web
}}</ref><ref>Template:Cite journal</ref> | ||
| KMT-2019-BLG-2073 | 0.19 | 59 | candidate; distance needed | 2020<ref>Template:Cite journal</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">Template:Citation</ref> | 2020<ref name=":0" /> | ||||
| VVV-2012-BLG-0472L | 10.5 | 3,337 | 3,200 | 2022<ref>Template:Cite journal</ref> | ||||
| MOA-9y-770L | 0.07 | Template:Val | 22,700 | 2023<ref name=":1">Template:Cite journal</ref> | ||||
| MOA-9y-5919L | 0.0012 or 0.0024 | Template:Val or Template:Val | 14,700 or 19,300 | 2023<ref name=":1" /> | ||||
| OGLE-2017-BLG-1170L | Template:Val | 24,700 | candidate | 2019<ref name="shah2019">Template:Cite journal</ref> | ||||
| Template:Val |
Discovered via transitEdit
| Exoplanet | Mass | Age
(Myr) |
Distance
(ly) |
Spectral type | Status | Stellar assoc. membership | Discovery |
|---|---|---|---|---|---|---|---|
| J1407b | Template:Sort | <451 | Candidate 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">Template:Cite journal</ref> | none | 2012, 2020<ref name="Kenworthy2020" /> |
See alsoEdit
- Template:Annotated link
- 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
- Rogue extragalactic planets – rogue planets outside the Milky Way galaxy
- Tidally detached exomoon – rogue planets that were originally moons
In fictionEdit
- A Pail of Air (1951) — a science fiction short story Fritz Leiber where Earth is pulled out of the Solar System by a black hole. Although the Earth is explicitly stated to orbit the black hole, the net effect is the same as ejecting it out of the Solar System as a rogue planet.<ref name=":27">{{#invoke:citation/CS1|citation
|CitationClass=web }}</ref><ref>Template:Cite magazine</ref>
- The Secret of the Ninth Planet (1959) — novel by Donald A. Wollheim in which Pluto is revealed to be a captured rogue planet with a surviving remnant civilization<ref name="SFEOuterPlanets">Template:Cite encyclopedia</ref>
- Space: 1999 (1975-77) — British science-fiction television programme where the Moon is ejected from the Solar System by a thermonuclear explosion<ref name=":27" />
- Remina (2004–2005) – horror manga by Junji Ito featuring a sentient rogue planet capable of eating planets and stars
- Melancholia (2011) – science fiction film by Lars von Trier about a rogue planet on a collision course with Earth
- Dark Eden (2012) – a social science fiction novel by Chris Beckett
- The Wandering Earth (2019) – a science fiction film directed by Frant Gwo about Earth being artificially moved from the Solar System to the Alpha Centauri system<ref name=":27" />
- Gemini Home Entertainment (2019–present) – horror anthology web series by Remy Abode, the main antagonist of which is a sentient rogue planet named "the Iris" that is masterminding an invasion of the Solar System, particularly Earth and Neptune<ref>{{#invoke:citation/CS1|citation
|CitationClass=web }}</ref>
- Carol & the End of the World (2023) – an animated adult comedy miniseries by Dan Guterman
- Rogue Planet (2002) - an episode of Star Trek: Enterprise
ReferencesEdit
BibliographyEdit
- "Possibility of Life Sustaining Planets in Interstellar Space" Article by Stevenson similar to the Nature article but with more information.
External linksEdit
Template:Sister project Template:Sister project
- Definition of a "Planet" (Resolution B5 – IAU)
- Strange New Worlds Could Make Miniature Solar Systems Robert Roy Britt (SPACE.com) 5 June 2006 11:35 am ET
- The IAU draft definition of "planet" and "plutons" press release (International Astronomical Union) 2006