Editing White dwarf (section)

== Debris disks and planets ==
{{see also|List of exoplanets and planetary debris around white dwarfs}}
[[File:Artist’s impression of debris around a white dwarf star.jpg|thumb|Artist's impression of debris around a white dwarf<ref>{{cite news |title=Hubble finds dead stars "polluted" with planetary debris |url=http://www.spacetelescope.org/images/heic1309a/ |access-date=10 May 2013 |newspaper=ESA/Hubble Press Release|archive-url=https://web.archive.org/web/20130609084315/http://www.spacetelescope.org/images/heic1309a/ |archive-date=9 June 2013 |url-status=live}}</ref>]]
[[File:Comet falling into white dwarf.jpg|left|thumb|Comet falling into white dwarf (artist's impression)<ref>{{cite web|title=Comet falling into white dwarf (artist's impression)|url=https://www.spacetelescope.org/images/heic1703a/|website=www.spacetelescope.org|access-date=14 February 2017|archive-url=https://web.archive.org/web/20170215024452/https://www.spacetelescope.org/images/heic1703a/|archive-date=15 February 2017|url-status=live}}</ref>]]
A white dwarf's [[stellar system|stellar]] and [[planetary system]] is inherited from its progenitor star and may interact with the white dwarf in various ways. There are several indications that a white dwarf has a remnant planetary system.

The most common observable evidence of a remnant planetary system is pollution of the spectrum of a white dwarf with [[Metallicity|metal]] absorption lines. 27–50% of white dwarfs show a spectrum polluted with metals,<ref>{{cite journal |last1=Koester |first1=D. |last2=Gänsicke |first2=B. T. |last3=Farihi |first3=J. |date=2014-06-01 |title=The frequency of planetary debris around young white dwarfs |bibcode=2014A&A...566A..34K |journal=Astronomy and Astrophysics |volume=566 |pages=A34 |doi=10.1051/0004-6361/201423691 |arxiv=1404.2617 |s2cid=119268896 |issn=0004-6361}}</ref> but these heavy elements settle out in the atmosphere of white dwarfs colder than {{val|20000|u=K}}. The most widely accepted hypothesis is that this pollution comes from [[Tidal force|tidally disrupted]] rocky bodies.<ref>{{cite journal |last=Jura |first=M. |date=2008-05-01 |title=Pollution of Single White Dwarfs by Accretion of Many Small Asteroids |bibcode=2008AJ....135.1785J |journal=The Astronomical Journal |volume=135 |issue=5 |pages=1785–1792 |doi=10.1088/0004-6256/135/5/1785 |arxiv=0802.4075 |s2cid=16571761 |issn=0004-6256}}</ref><ref name=":2" /> The first observation of a metal-polluted white dwarf was by van Maanen<ref name="van Maanen" /> in 1917 at the [[Mount Wilson Observatory]] and is now recognized as the first evidence of [[exoplanet]]s in astronomy.<ref name="Klein 61">{{cite journal |last1=Klein |first1=Beth L. |last2=Doyle |first2=Alexandra E. |last3=Zuckerman |first3=B. |last4=Dufour |first4=P. |last5=Blouin |first5=Simon |last6=Melis |first6=Carl |last7=Weinberger |first7=Alycia J. |last8=Young |first8=Edward D. |date=2021-06-01 |title=Discovery of Beryllium in White Dwarfs Polluted by Planetesimal Accretion |bibcode=2021ApJ...914...61K |journal=The Astrophysical Journal |volume=914 |issue=1 |page=61 |doi=10.3847/1538-4357/abe40b |arxiv=2102.01834 |s2cid=231786441 |issn=0004-637X |doi-access=free }}</ref> The white dwarf [[van Maanen 2]] shows iron, [[calcium]] and magnesium in its atmosphere,<ref>{{cite conference |conference=19Th European Workshop on White Dwarfs |last=Zuckerman |first=B. |date=2015-06-01 |title=Recognition of the First Observational Evidence of an Extrasolar Planetary System |bibcode=2015ASPC..493..291Z |volume=493 |page=291}}</ref> but van Maanen misclassified it as the faintest [[F-type star]] based on the calcium [[Fraunhofer lines|H- and K-lines]].<ref>{{cite journal |last=Farihi |first=J. |date=2016-04-01 |title=Circumstellar debris and pollution at white dwarf stars |bibcode=2016NewAR..71....9F |journal=New Astronomy Reviews |volume=71 |pages=9–34 |doi=10.1016/j.newar.2016.03.001 |arxiv=1604.03092 |s2cid=118486264 |issn=1387-6473}}</ref> The [[nitrogen]] in white dwarfs is thought to come from nitrogen-ice of extrasolar [[Kuiper Belt objects]], the lithium is thought to come from accreted [[Crust (geology)|crust]] material and the beryllium is thought to come from [[exomoon]]s.<ref name="Klein 61"/>

A less common observable evidence is infrared excess due to a flat and optically thick debris disk, which is found in around 1%–4% of white dwarfs.<ref name=":2" /> The first white dwarf with infrared excess was discovered by Zuckerman and Becklin in 1987 in the near-infrared around [[G 29-38|Giclas 29-38]]<ref>{{cite journal |last1=Zuckerman |first1=B. |last2=Becklin |first2=E. E. |date=1987-11-01 |title=Excess infrared radiation from a white dwarf—an orbiting brown dwarf? |bibcode=1987Natur.330..138Z |journal=Nature |volume=330 |issue=6144 |pages=138–140 |doi=10.1038/330138a0 |s2cid=4357883 |issn=0028-0836}}</ref> and later confirmed as a debris disk.<ref name=":3" /> White dwarfs hotter than {{val|27000|u=K}} sublimate all the dust formed by tidally disrupting a rocky body, preventing the formation of a debris disk. In colder white dwarfs, a rocky body might be tidally disrupted near the [[Roche radius]] and forced into a circular orbit by the [[Poynting–Robertson drag]], which is stronger for less massive white dwarfs. The Poynting–Robertson drag will also cause the dust to orbit closer and closer towards the white dwarf, until it will eventually sublimate and the disk will disappear. A debris disk will have a lifetime of around a few million years for white dwarfs hotter than {{val|10000|u=K}}. Colder white dwarfs can have disk-lifetimes of a few 10 million years, which is enough time to tidally disrupt a second rocky body and forming a second disk around a white dwarf, such as the two rings around [[LSPM J0207+3331]].<ref>{{cite journal |last1=Steckloff |first1=Jordan K. |last2=Debes |first2=John |last3=Steele |first3=Amy |last4=Johnson |first4=Brandon |last5=Adams |first5=Elisabeth R. |last6=Jacobson |first6=Seth A. |last7=Springmann |first7=Alessondra |date=2021-06-01 |title=How Sublimation Delays the Onset of Dusty Debris Disk Formation around White Dwarf Stars |bibcode=2021ApJ...913L..31S |journal=The Astrophysical Journal |volume=913 |issue=2 |pages=L31 |doi=10.3847/2041-8213/abfd39 |pmid=35003618 |pmc=8740607 |arxiv=2104.14035 |issn=0004-637X |doi-access=free }}</ref>

The least common observable evidence of planetary systems are detected major or minor planets. Only a handful of giant planets and a handful of minor planets are known around white dwarfs.<ref name=":4">{{cite book |last=Veras |first=Dimitri |bibcode=2021orel.bookE...1V |arxiv=2106.06550 |chapter=Planetary Systems Around White Dwarfs |title=Oxford Research Encyclopedia of Planetary Science |doi=10.1093/acrefore/9780190647926.013.238 |publisher=Oxford University Press |date=2021-10-01|isbn=978-0-19-064792-6 }}</ref><ref name="Mullally2024">{{cite journal |last1=Mullally |first1=Susan E. |last2=Debes |first2=John |last3=Cracraft |first3=Misty |last4=Mullally |first4=Fergal |last5=Poulsen |first5=Sabrina |last6=Albert |first6=Loic |last7=Thibault |first7=Katherine |last8=Reach |first8=William T. |last9=Hermes |first9=J. J. |last10=Barclay |first10=Thomas |last11=Kilic |first11=Mukremin |last12=Quintana |first12=Elisa V. |date=24 Jan 2024 |title=JWST Directly Images Giant Planet Candidates Around Two Metal-Polluted White Dwarf Stars |journal=The Astrophysical Journal Letters |volume=962 |issue=2 |pages=L32 |doi=10.3847/2041-8213/ad2348 |doi-access=free |arxiv=2401.13153|bibcode=2024ApJ...962L..32M }}</ref> {{multiple image |header=Exoplanet orbits WD 1856+534 |align=right |direction=vertical |width= |image1=Artist’s impression of WD 1856b (noirlab2023a).jpg |caption1= |width1=250 |image2=NASA-ExoplanetOrbitingWhiteDwarfStarWD1856+534.webm |caption2=<div align="center">([[:File:NASA-ExoplanetOrbitingWhiteDwarfStarWD1856+534.webm|NASA; video; 2:10]])</div> |width2=250 |footer= }}Infrared spectroscopic observations made by NASA's [[Spitzer Space Telescope]] of the central star of the [[Helix Nebula]] suggest the presence of a dust cloud, which may be caused by cometary collisions. It is possible that infalling material from this may cause X-ray emission from the central star.<ref>{{cite news |url=http://news.bbc.co.uk/1/hi/sci/tech/6357765.stm |title=Comet clash kicks up dusty haze |archive-url=https://web.archive.org/web/20070216010400/http://news.bbc.co.uk/1/hi/sci/tech/6357765.stm |archive-date=16 February 2007 |work=BBC News |date=13 February 2007 |access-date=20 September 2007}}</ref><ref>
{{cite journal
 |bibcode=2007ApJ...657L..41S
 |arxiv= astro-ph/0702296
 |doi= 10.1086/513018
 |title=A Debris Disk around the Central Star of the Helix Nebula?
 |date=2007
 |last1=Su |first1=K. Y. L.
 |last2=Chu |first2=Y.-H.
 |last3=Rieke |first3=G. H.
 |last4=Huggins |first4=P. J.
 |last5=Gruendl |first5=R.
 |last6=Napiwotzki |first6=R.
 |last7=Rauch |first7=T.
 |last8=Latter |first8=W. B.
 |last9=Volk |first9=K.
 |journal=The Astrophysical Journal
 |volume=657 |issue= 1
 |pages=L41
 |s2cid= 15244406
}}</ref> Similarly, observations made in 2004 indicated the presence of a dust cloud around the young (estimated to have formed from its AGB progenitor about 500&nbsp;million years ago) white dwarf [[G29-38]], which may have been created by tidal disruption of a [[comet]] passing close to the white dwarf.<ref name=":3">
{{cite journal
 |bibcode=2005ApJ...635L.161R
 |arxiv= astro-ph/0511358
 |doi= 10.1086/499561
 |title=The Dust Cloud around the White Dwarf G29-38
 |date=2005
 |last1=Reach |first1=William T.
 |last2=Kuchner |first2=Marc J.
 |last3=Von Hippel |first3=Ted
 |last4=Burrows |first4=Adam
 |last5=Mullally |first5=Fergal
 |last6=Kilic |first6=Mukremin
 |last7=Winget |first7=D. E.
 |journal=The Astrophysical Journal
 |volume=635 |issue=2 |page=L161
 |s2cid= 119462589
}}</ref> Some estimations based on the metal content of the atmospheres of the white dwarfs consider that at least 15% of them may be orbited by planets or [[asteroid]]s, or at least their debris.<ref>{{cite journal |author1=Sion, Edward M. |author2=Holberg, J.B. |author3=Oswalt, Terry D. |author4=McCook, George P. |author5=Wasatonic, Richard |title=The White Dwarfs Within 20&nbsp;Parsecs of the Sun: Kinematics and Statistics |date=2009 |journal=The Astronomical Journal |volume=138 |number=6 |pages=1681–1689 |bibcode=2009AJ....138.1681S |doi=10.1088/0004-6256/138/6/1681 |arxiv=0910.1288|s2cid=119284418 }}</ref> Another suggested idea is that white dwarfs could be orbited by the stripped cores of [[rocky planet]]s, that would have survived the red giant phase of their star but losing their outer layers and, given those planetary remnants would likely be made of [[metal]]s, to attempt to detect them looking for the signatures of their interaction with the white dwarf's [[magnetic field]].<ref>{{cite journal |author1=Li, Jianke |author2=Ferrario, Lilia |author3=Wickramasinghe, Dayal |title=Planets around White Dwarfs |year=1998 |journal=Astrophysical Journal Letters |volume=503 |page=L151 |number=1 |id=p. L51 |bibcode=1998ApJ...503L.151L |doi=10.1086/311546 |doi-access=free}}</ref> Other suggested ideas of how white dwarfs are polluted with dust involve the scattering of asteroids by planets<ref>{{cite journal |last1=Debes |first1=John H. |last2=Walsh|first2=Kevin J. |last3=Stark |first3=Christopher |date=24 February 2012 |journal=The Astrophysical Journal |language=en |volume=747 |issue=2 |page=148 |arxiv=1201.0756 |doi=10.1088/0004-637X/747/2/148 |issn=0004-637X |title=The Link Between Planetary Systems, Dusty White Dwarfs, and Metal-Polluted White Dwarfs|bibcode=2012ApJ...747..148D |s2cid=118688656 }}</ref><ref>{{cite journal |last1=Veras |first1=Dimitri |last2=Gänsicke |first2=Boris T. |date=2015-02-21|title=Detectable close-in planets around white dwarfs through late unpacking|journal=Monthly Notices of the Royal Astronomical Society |language=en |volume=447 |issue=2 |pages=1049–1058 |arxiv=1411.6012 |doi=10.1093/mnras/stu2475 |doi-access=free |issn=0035-8711 |bibcode=2015MNRAS.447.1049V|s2cid=119279872 }}</ref><ref>{{cite journal |last1=Frewen |first1=S. F. N. |last2=Hansen |first2=B. M. S. |date=2014-04-11|title=Eccentric planets and stellar evolution as a cause of polluted white dwarfs |journal=Monthly Notices of the Royal Astronomical Society |language=en |volume=439 |issue=3 |pages=2442–2458 |arxiv=1401.5470 |doi=10.1093/mnras/stu097 |doi-access=free |issn=0035-8711 |bibcode=2014MNRAS.439.2442F|s2cid=119257046 }}</ref> or via planet-planet scattering.<ref>{{cite journal |last1=Bonsor |first1=Amy |last2=Gänsicke |first2=Boris T. |last3=Veras |first3=Dimitri |last4=Villaver |first4=Eva|last5=Mustill |first5=Alexander J. |date=2018-05-21|title=Unstable low-mass planetary systems as drivers of white dwarf pollution |journal=Monthly Notices of the Royal Astronomical Society |language=en |volume=476 |issue=3 |pages=3939–3955 |arxiv=1711.02940 |doi=10.1093/mnras/sty446 |doi-access=free |issn=0035-8711 |bibcode=2018MNRAS.476.3939M|s2cid=4809366 }}</ref> Liberation of [[exomoon]]s from their host planet could cause white dwarf pollution with dust. Either the liberation could cause asteroids to be scattered towards the white dwarf or the exomoon could be scattered into the [[Roche radius]] of the white dwarf.<ref>{{cite journal |last1=Gänsicke |first1=Boris T. |last2=Holman |first2=Matthew J. |last3=Veras |first3=Dimitri |last4=Payne |first4=Matthew J. |date=2016-03-21|title=Liberating exomoons in white dwarf planetary systems|journal=Monthly Notices of the Royal Astronomical Society |language=en |volume=457 |issue=1 |pages=217–231 |arxiv=1603.09344 |doi=10.1093/mnras/stv2966 |doi-access=free |issn=0035-8711 |bibcode=2016MNRAS.457..217P|s2cid=56091285 }}</ref> The mechanism behind the pollution of white dwarfs in binaries was also explored as these systems are more likely to lack a major planet, but this idea cannot explain the presence of dust around single white dwarfs.<ref>{{cite journal |last1=Rebassa-Mansergas |first1=Alberto |last2=Xu (许偲艺) |first2=Siyi |last3=Veras |first3=Dimitri |date=2018-01-21|title=The critical binary star separation for a planetary system origin of white dwarf pollution |journal=Monthly Notices of the Royal Astronomical Society |language=en |volume=473 |issue=3 |pages=2871–2880 |arxiv=1708.05391 |doi=10.1093/mnras/stx2141 |doi-access=free |issn=0035-8711 |bibcode=2018MNRAS.473.2871V|s2cid=55764122 }}</ref> While old white dwarfs show evidence of dust accretion, white dwarfs older than ~1 billion years or >7000 K with dusty infrared excess were not detected<ref>{{cite journal |last1=Becklin |first1=E. E. |last2=Zuckerman |first2=B. |last3=Farihi |first3=J. |date=10 February 2008 |title=Spitzer IRAC Observations of White Dwarfs. I. Warm Dust at Metal-Rich Degenerates |journal=The Astrophysical Journal |language=en |volume=674 |issue=1 |pages=431–446 |arxiv=0710.0907 |doi=10.1086/521715 |issn=0004-637X |bibcode=2008ApJ...674..431F|s2cid=17813180 }}</ref> until the discovery of LSPM J0207+3331 in 2018, which has a cooling age of ~3 billion years. The white dwarf shows two dusty components that are being explained with two rings with different temperatures.<ref name=":2">{{cite journal |last1=Debes |first1=John H. |last2=Thévenot |first2=Melina |last3=Kuchner |first3=Marc J. |last4=Burgasser |first4=Adam J. |last5=Schneider |first5=Adam C. |last6=Meisner |first6=Aaron M. |last7=Gagné |first7=Jonathan |last8=Faherty |first8=Jacqueline K.|author8-link=Jackie Faherty |last9=Rees |first9=Jon M. |date=2019-02-19|title=A 3 Gyr White Dwarf with Warm Dust Discovered via the Backyard Worlds: Planet 9 Citizen Science Project |journal=The Astrophysical Journal |volume=872 |issue=2|page=L25 |arxiv=1902.07073 |doi=10.3847/2041-8213/ab0426 |issn=2041-8213 |bibcode=2019ApJ...872L..25D|s2cid=119359995 |doi-access=free }}</ref>

Another possible way to detect planetary systems around white dwarfs is through their radio emissions.  In 2004 and 2005, A. J. Willes and K. Wu hypothesized that when an exoplanet travels through the [[magnetosphere]] of a white dwarf, it may generate auroral radio emissions from the magnetic poles of the white dwarf, similar to how [[Io (moon)|Io]] stimulates [[Magnetosphere of Jupiter|radio emissions from Jupiter]].  However, a search for such radio emission from nine white dwarfs by researchers using the [[Arecibo Observatory|Arecibo radio telescope]] did not find any so far.<ref name=Route2024/>

The metal-rich white dwarf [[WD 1145+017]] is the first white dwarf observed with a disintegrating minor planet that transits the star.<ref>{{cite web |title = Zombie Star Caught Feasting on Asteroids |url=http://news.nationalgeographic.com/2015/10/151021-zombie-dead-star-eats-asteroid-astronomy/ |website=National Geographic News |access-date=2015-10-22|first=Michael D. |last=Lemonick |date=2015-10-21 |archive-url=https://web.archive.org/web/20151024081958/http://news.nationalgeographic.com/2015/10/151021-zombie-dead-star-eats-asteroid-astronomy/ |archive-date=24 October 2015 |url-status=dead}}</ref><ref name=":1">{{cite journal |title=A disintegrating minor planet transiting a white dwarf |journal=Nature |date=2015-10-22|pages=546–549 |volume=526 |issue=7574 |doi=10.1038/nature15527 |language = en |first1=Andrew |last1=Vanderburg |first2=John Asher |last2=Johnson |first3=Saul |last3=Rappaport |first4=Allyson |last4=Bieryla |first5=Jonathan |last5=Irwin |first6=John Arban |last6=Lewis |first7=David |last7=Kipping |first8=Warren R. |last8=Brown |first9=Patrick |last9=Dufour |arxiv=1510.06387 |bibcode=2015Natur.526..546V |pmid=26490620|s2cid=4451207 }}</ref> The disintegration of the planetesimal generates a debris cloud that passes in front of the star every 4.5&nbsp;hours, causing a 5-minute-long fade in the star's optical brightness.<ref name=":1" /> The depth of the transit is highly variable.<ref name=":1" />

The giant planet [[WD J0914+1914]]b is being [[Photoevaporation|evaporated]] by the strong ultraviolet radiation of the hot white dwarf. Part of the evaporated material is being accreted in a gaseous disk around the white dwarf. The weak [[H-alpha|hydrogen line]] as well as other lines in the spectrum of the white dwarf revealed the presence of the giant planet.<ref name="Gänsicke">{{cite web |last1=Gänsicke |first1=Boris T. |last2=Schreiber |first2=Matthias R. |last3=Toloza |first3=Odette |last4=Gentile Fusillo |first4=Nicola P. |last5=Koester |first5=Detlev |last6=Manser |first6=Christopher J. |title=Accretion of a giant planet onto a white dwarf |url=https://www.eso.org/public/archives/releases/sciencepapers/eso1919/eso1919a.pdf |url-status=live |archive-url=https://web.archive.org/web/20191204215002/https://www.eso.org/public/archives/releases/sciencepapers/eso1919/eso1919a.pdf |archive-date=4 December 2019 |access-date=2019-12-11 |website=ESO}}</ref>

The white dwarf [[WD 0145+234]] shows brightening in the mid-infrared, seen in [[NEOWISE]] data. The brightening, not seen before 2018, may be due to the [[Roche limit|tidal disruption]] of an [[exoasteroid]], the first time such an event has been observed.<ref name=":5">{{cite journal |last1=Wang |first1=Ting-Gui |last2=Jiang |first2=Ning |last3=Ge |first3=Jian |last4=Cutri |first4=Roc M. |last5=Jiang |first5=Peng |last6=Sheng |first6=Zhengfeng |last7=Zhou |first7=Hongyan |last8=Bauer |first8=James |last9=Mainzer |first9=Amy |last10=Wright |first10=Edward L. |date=November 2019 |title=An On-going Mid-infrared Outburst in the White Dwarf 0145+234: Catching in Action of Tidal Disruption of an Exoasteroid? |arxiv=1910.04314 |journal=Astrophysical Journal Letters |volume=886 |number=1 |page=L5 |doi=10.3847/2041-8213/ab53ed |doi-access=free |bibcode=2019ApJ...886L...5W }}</ref>

[[WD 1856+534]] is the first transiting major planet to be observed orbiting a white dwarf, and remains the only such example as of 2023.<ref name="Vanderburg2020">
{{cite journal
 |title      = A giant planet candidate transiting a white dwarf
 |display-authors = etal
 |first1     = Andrew  |last1 = Vanderburg
 |first2     = Saul A. |last2 = Rappaport
 |first3     = Siyi |last3 = Xu
 |first4     = Ian J. M. |last4 = Crossfield
 |first5     = Juliette C. |last5 = Becker
 |first6     = Bruce |last6 = Gary
 |date       = September 2020
 |journal    = Nature
 |volume     = 585
 |issue = 7825
 |pages      = 363–367
 |doi        = 10.1038/s41586-020-2713-y
 |pmid = 32939071
 |arxiv      = 2009.07282
 |bibcode    = 2020Natur.585..363V
}}</ref><ref>
{{cite journal
 |first=David
 |last=Kipping
 |title=The giant nature of WD 1856 b implies that transiting rocky planets are rare around white dwarfs
 |journal=Monthly Notices of the Royal Astronomical Society
 |volume=527
 |number=2
 |date=January 2024
 |pages=3532–3541
 |doi=10.1093/mnras/stad3431|doi-access=free
 |arxiv=2310.15219
}}</ref> [[MOA-2010-BLG-477L]], a white dwarf discovered thanks to a [[microlensing event]], is also known to have a giant planet.<ref name=Blackman2021>
{{cite journal
 |arxiv=2110.07934
 |year=2021
 |title=A Jovian analogue orbiting a white dwarf star
 |doi=10.1038/s41586-021-03869-6
 |last1=Blackman |first1=J. W.
 |last2=Beaulieu |first2=J. P.
 |last3=Bennett |first3=D. P.
 |last4=Danielski |first4=C.
 |last5=Alard |first5=C.
 |last6=Cole |first6=A. A.
 |last7=Vandorou |first7=A.
 |last8=Ranc |first8=C.
 |last9=Terry |first9=S. K.
 |last10=Bhattacharya |first10=A.
 |last11=Bond |first11=I.
 |last12=Bachelet |first12=E.
 |last13=Veras |first13=D.
 |last14=Koshimoto |first14=N.
 |last15=Batista |first15=V.
 |last16=Marquette |first16=J. B.
 |journal=Nature |volume=598 |issue=7880 |pages=272–275 |pmid=34646001
 |bibcode=2021Natur.598..272B
}}</ref><ref name="Mullally2024"/>

[[GD 140]] and [[LP 145-141|LAWD 37]] are suspected to have giant exoplanets due to anomaly in the [[Hipparcos]]-Gaia proper motion. For GD 140 it is suspected to be a planet several times more massive than Jupiter and for LAWD 37 it is suspected to be a planet less massive than Jupiter.<ref>{{cite journal |last1=Kervella |first1=Pierre |last2=Arenou |first2=Frédéric |last3=Mignard |first3=François |last4=Thévenin |first4=Frédéric |date=2019-03-01 |title=Stellar and substellar companions of nearby stars from Gaia DR2. Binarity from proper motion anomaly |url=https://ui.adsabs.harvard.edu/abs/2019A&A...623A..72K |journal=Astronomy and Astrophysics |volume=623 |pages=A72 |doi=10.1051/0004-6361/201834371 |arxiv=1811.08902 |bibcode=2019A&A...623A..72K |s2cid=119491061 |issn=0004-6361}}</ref><ref>{{cite journal |last1=Kervella |first1=Pierre |last2=Arenou |first2=Frédéric |last3=Thévenin |first3=Frédéric |date=2022-01-01 |title=Stellar and substellar companions from Gaia EDR3. Proper-motion anomaly and resolved common proper-motion pairs |url=https://ui.adsabs.harvard.edu/abs/2022A&A...657A...7K |journal=Astronomy and Astrophysics |volume=657 |pages=A7 |doi=10.1051/0004-6361/202142146 |arxiv=2109.10912 |bibcode=2022A&A...657A...7K |s2cid=237605138 |issn=0004-6361}}</ref> Additionally, WD 0141-675 was suspected to have a super-Jupiter with an orbital period of 33.65 days based on Gaia astrometry. This is remarkable because WD 0141-675 is polluted with metals and metal polluted white dwarfs have long been suspected to host giant planets that disturb the orbits of minor planets, causing the pollution.<ref name="GaiaDR3">{{cite journal |last1=Gaia Collaboration |last2=Arenou |first2=F. |last3=Babusiaux |first3=C. |last4=Barstow |first4=M. A. |last5=Faigler |first5=S. |last6=Jorissen |first6=A. |last7=Kervella |first7=P. |last8=Mazeh |first8=T. |last9=Mowlavi |first9=N. |last10=Panuzzo |first10=P. |last11=Sahlmann |first11=J. |last12=Shahaf |first12=S. |last13=Sozzetti |first13=A. |last14=Bauchet |first14=N. |last15=Damerdji |first15=Y. |date=2023 |title=''Gaia'' Data Release 3 |journal=Astronomy & Astrophysics |volume=674 |pages=A34 |doi=10.1051/0004-6361/202243782 |arxiv=2206.05595 |s2cid=249626026 }}</ref> Both GD 140 and WD 0141 will be observed with [[James Webb Space Telescope|JWST]] in cycle 2 with the aim to detect infrared excess caused by the planets.<ref>{{cite web |title=CYCLE 2 GO |url=https://www.stsci.edu/home/jwst/science-execution/approved-programs/general-observers/cycle-2-go |access-date=2023-05-15 |website=STScI.edu |language=en}}</ref> However, the planet candidate at WD 0141-675 was found to be a false positive caused by a software error.<ref>{{cite web |url=https://www.cosmos.esa.int/web/gaia/dr3-known-issues |title=Gaia DR3 known issues |date=5 May 2023 |publisher=[[ESA]] |access-date=8 August 2023 |quote=During validation of epoch astrometry for Gaia DR4, an error was discovered, that had already had an impact on the Gaia DR3 non-single star results. [...] We can conclude that the solutions for [...] WD 0141-675 [...] are false-positives as far as Gaia non-single star processing is concerned.}}</ref>