View source for Astronomy:Disrupted planet

{{Short description|Planet or related being destroyed by a passing object}}
[[File:Artist's impression of a white dwarf devouring a minor planet.jpg|thumb|right|250px|Artist concept of a rocky planetary object being vaporized by its parent star]]
In [[Astronomy:Astronomy|astronomy]], a '''disrupted planet'''<ref name="SN-20171222">{{cite web |author=Staff |title=Young Star RZ Piscium is 'Eating' Its Own Planets, Astronomers Say |url=http://www.sci-news.com/astronomy/young-star-rz-piscium-eating-planets-05561.html |date=22 December 2017 |work=Sci-News.com |access-date=23 December 2017 }}</ref><ref name="IU-20171221">{{cite web |last=Fryling |first=Kevin |title=IU astronomer's analysis helps discover that a star in the constellation Pisces is a 'planet-eater' |url=https://news.iu.edu/stories/2017/12/iub/21-science-planet-eating-star.html |date=21 December 2017 |work=[[Organization:Indiana University|Indiana University]] |access-date=23 December 2017 }}</ref> is a [[Astronomy:Planet|planet]] or [[Astronomy:Exoplanet|exoplanet]] or, perhaps on a somewhat smaller scale, a [[Astronomy:Planetary-mass object|planetary-mass object]], [[Astronomy:Planetesimal|planetesimal]], [[Astronomy:Moon|moon]], [[Astronomy:Exomoon|exomoon]] or [[Astronomy:Asteroid|asteroid]] that has been disrupted or destroyed by a nearby or passing astronomical body or object such as a [[Astronomy:Star|star]].<ref name="SN-20171222" /><ref name="IU-20171221" /> '''Necroplanetology''' is the related study of such a process.<ref name="SA-20200328">{{cite news |last=Starr |first=Michelle |title=Necroplanetology: The Strangest Field of Astronomy You've Never Heard Of |url=https://www.sciencealert.com/necroplanetology-the-study-of-planets-dismembered-remains |date=28 March 2020 |work=ScienceAlert.com |access-date=30 March 2020 }}</ref><ref name="ARX-20200318">{{cite journal |last1=Duvvuri |first1=Girish M. |last2=Redfield |first2=Seth |last3=Veras |first3=Dimitri |title=Necroplanetology: Simulating the Tidal Disruption of Differentiated Planetary Material Orbiting WD 1145+017 |journal=The Astrophysical Journal |date=18 March 2020 |volume=893 |issue=2 |page=166 |doi=10.3847/1538-4357/ab7fa0 |arxiv=2003.08410 |bibcode=2020ApJ...893..166D |s2cid=213004256 |doi-access=free }}</ref> 

The result of such a disruption may be the production of excessive amounts of related gas, [[Astronomy:Cosmic dust|dust]] and debris,<ref name="AJ-20171221">{{cite journal |last1=Punzi |first1=K. M. |last2=Kastner |first2=J. H. |last3=Melis |first3=C. |last4=Zuckerman |first4=B. |last5=Pilachowski |first5=C. |last6=Gingerich |first6=L. |last7=Knapp |first7=T. |title=Is the Young Star RZ Piscium Consuming Its Own (Planetary) Offspring? |doi=10.3847/1538-3881/aa9524 |date=21 December 2017 |journal=[[Astronomy:The Astronomical Journal|The Astronomical Journal]] |volume=155 |pages=33 |number=1 |bibcode=2018AJ....155...33P |arxiv=1712.08962 |s2cid=119530135 |doi-access=free }}</ref> which may eventually surround the parent star in the form of a circumstellar disk or [[Astronomy:Debris disk|debris disk]]. As a consequence, the orbiting debris field may be an "[[Astronomy:KIC 8462852#Circumstellar dust ring|uneven ring of dust]]", causing erratic light fluctuations in the apparent [[Astronomy:Luminosity|luminosity]] of the parent star, as may have been responsible for the oddly flickering [[Astronomy:Light curve|light curve]]s associated with the starlight observed from certain [[Astronomy:Variable star|variable star]]s, such as that from  [[Astronomy:Tabby's Star|Tabby's Star]] (KIC 8462852), [[Astronomy:RZ Piscium|RZ Piscium]] and [[Astronomy:WD 1145+017|WD 1145+017]].<ref name="SA-20200328" /><ref name="ARX-20200318" /> Excessive amounts of [[Physics:Infrared|infrared radiation]] may be detected from such stars,<ref name="ARX-201090310">{{Cite journal|last1=Farihi |first1=J. |last2=Jura |first2=M. |last3=Zuckerman |first3=B. |title=Infrared Signatures of Disrupted Minor Planets at White Dwarfs |journal=The Astrophysical Journal |volume=694 |issue=2 |pages=805–819 |date=10 March 2009 |arxiv=0901.0973|doi=10.1088/0004-637X/694/2/805 |bibcode=2009ApJ...694..805F |s2cid=14171378 }}</ref> suggestive evidence in itself that dust and debris may be orbiting the stars.<ref name="AJ-20171221" /><ref name="NASA-20171004">{{cite web |last=Landau |first=Elizabeth |title=Mysterious Dimming of Tabby's Star May Be Caused by Dust |url=https://www.jpl.nasa.gov/news/news.php?feature=6963 |date=4 October 2017 |work=[[Organization:NASA|NASA]] |access-date=23 December 2017 }}</ref><ref name="ApJ-20171003">{{cite journal |author=Meng, Huan Y.A.|display-authors=et al |title=Extinction and the Dimming of KIC 8462852 |date=3 October 2017 |journal=[[Astronomy:The Astrophysical Journal|The Astrophysical Journal]] |volume=847 |number=2 |page=131 |doi=10.3847/1538-4357/aa899c |bibcode=2017ApJ...847..131M |arxiv=1708.07556 |s2cid=118875846 |doi-access=free }}</ref><ref name="PHY-20171005">{{cite web |last=Tabor |first=Abby |title=The scientific quest to explain Kepler's most enigmatic find |url=https://phys.org/news/2017-10-scientific-quest-kepler-enigmatic.html |date=5 October 2017 |work=Phys.org |access-date=23 December 2017 }}</ref>

== Examples ==
===Planets===
Examples of planets, or their related remnants, considered to have been a disrupted planet, or part of such a planet, include:  ‘Oumuamua<ref name="ARX-2017">{{Cite journal|last=Ćuk |first=Matija |arxiv=1712.01823 |title=1I/ʻOumuamua as a Tidal Disruption Fragment From a Binary Star System |journal=The Astrophysical Journal |volume=852 |issue=1 |pages=L15 |date=2017 |doi=10.3847/2041-8213/aaa3db |bibcode=2018ApJ...852L..15C |s2cid=54959652 |doi-access=free }}</ref> and [[Astronomy:WD 1145+017 b|WD 1145+017 b]], as well as [[Astronomy:Asteroid|asteroid]]s,<ref name="ARX-20060816">{{cite journal |last=Soter |first=Steven |title=What is a Planet? |date=2006 |journal= The Astronomical Journal|volume=132 |issue=6 |pages=2513–2519 |arxiv=astro-ph/0608359 |doi=10.1086/508861|bibcode=2006AJ....132.2513S |s2cid=14676169 }}</ref> [[Astronomy:Hot Jupiter|hot Jupiter]]s<ref name="MNRAS-20110920">{{cite journal |last=Nayakshin |first=Sergei |title=Hot Super Earths: disrupted young jupiters? |url=https://academic.oup.com/mnras/article/416/4/2974/976497 |date=20 September 2011 |journal=[[Organization:Monthly Notices of the Royal Astronomical Society|Monthly Notices of the Royal Astronomical Society]] |volume=416 |issue=4 |pages=2974–2980 |doi=10.1111/j.1365-2966.2011.19246.x |access-date=25 December 2017 |bibcode=2011MNRAS.416.2974N |arxiv=1103.1846 |s2cid=53960650 }}</ref> and those that are hypothetical planets, like [[Astronomy:Fifth planet (hypothetical)|Fifth planet]], [[Astronomy:Phaeton (hypothetical planet)|Phaeton]], [[Astronomy:Planet V|Planet V]]  and [[Astronomy:Theia (planet)|Theia]].

===Stars===
Examples of parent stars considered to have disrupted a planet include: [[Astronomy:EPIC 204278916|EPIC 204278916]], Tabby's Star (KIC 8462852), [[Astronomy:PDS 110|PDS 110]], [[Astronomy:RZ Piscium|RZ Piscium]], [[Astronomy:WD 1145+017|WD 1145+017]] and [[Astronomy:47 Ursae Majoris|47 Ursae Majoris]].
[[File:PIA22081-KIC8462852-TabbysStar-UnevenDustRing-Illustration-20171004.png|thumb|center|500px|{{center|Artist concept of an "uneven ring of dust" surrounding Tabby's Star}}]]
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==Tabby's Star light curve==
[[Astronomy:Tabby's Star|Tabby's Star]] (KIC 8462852) is an [[Astronomy:F-type main-sequence star|F-type main-sequence star]] exhibiting unusual light fluctuations, including up to a 22% dimming in brightness.<ref>{{Cite journal|last1=Boyajian|first1=T. S.|last2=LaCourse|first2=D. M.|last3=Rappaport|first3=S. A.|last4=Fabrycky|first4=D.|last5=Fischer|first5=D. A.|last6=Gandolfi|first6=D.|last7=Kennedy|first7=G. M.|last8=Korhonen|first8=H.|last9=Liu|first9=M. C.|date=2016-01-27|title=Planet Hunters IX. KIC&nbsp;8462852 – where's the flux?|url=https://academic.oup.com/mnras/article-abstract/457/4/3988/2589003?redirectedFrom=fulltext|journal=Monthly Notices of the Royal Astronomical Society|language=en|volume=457|issue=4|pages=3988–4004|doi=10.1093/mnras/stw218|issn=0035-8711|arxiv=1509.03622|bibcode=2016MNRAS.457.3988B|s2cid=54859232}}</ref> Several hypotheses have been proposed to explain these irregular changes, but none to date fully explain all aspects of the curve. One explanation is that an "[[Astronomy:KIC 8462852#Circumstellar dust ring|uneven ring of dust]]" orbits Tabby's Star.<ref>{{Cite web|url=https://www.jpl.nasa.gov/news/news.php?feature=6963|title=Mysterious Dimming of Tabby's Star May Be Caused by Dust|website=NASA/JPL|access-date=2018-11-13}}</ref><ref>{{Cite journal|last1=Boyajian|first1=Tabetha S.|last2=Alonso|first2=Roi|last3=Ammerman|first3=Alex|last4=Armstrong|first4=David|last5=Ramos|first5=A. Asensio|last6=Barkaoui|first6=K.|last7=Beatty|first7=Thomas G.|last8=Benkhaldoun|first8=Z.|last9=Benni|first9=Paul|date=2018-01-19|title=The First Post-Kepler Brightness Dips of KIC 8462852|journal=The Astrophysical Journal|volume=853|issue=1|pages=L8|doi=10.3847/2041-8213/aaa405|issn=2041-8213|arxiv=1801.00732|bibcode=2018ApJ...853L...8B|s2cid=215751718 |doi-access=free }}</ref> However, in September 2019, astronomers reported that the observed dimmings of Tabby's Star may have been produced by fragments resulting from the disruption of an orphaned [[Astronomy:Exomoon|exomoon]].<ref name="PHYS-20190916">{{cite news |author=Columbia University |title=New observations help explain the dimming of Tabby's Star |url=https://phys.org/news/2019-09-dimming-tabby-star.html |date=16 September 2019 |work=Phys.org |access-date=16 September 2019 |author-link=Columbia University }}</ref><ref name="MNRAS-20190915">{{cite journal |last1=Marinez |first1=Miquel |last2=Stone |first2=Nicholas C. |last3=Metzger |first3=Brian D. |title=Orphaned Exomoons: Tidal Detachment and Evaporation Following an Exoplanet-Star Collision |date=5 September 2019 |journal=[[Organization:Monthly Notices of the Royal Astronomical Society|Monthly Notices of the Royal Astronomical Society]] |volume=489 |issue=4 |pages=5119–5135 |doi=10.1093/mnras/stz2464 |arxiv=1906.08788 |bibcode=2019MNRAS.489.5119M |s2cid=195316956 }}</ref>
{{panorama
|image=File:Consolidated plot of KIC 8462852 dip maxima March 2020 update.png
|height=300
|caption={{center|Consolidated plot of all known dimmings (as of 1 March 2020)}}
}}

<gallery class="center" widths="150px">
File:KIC 8462852 - gesamte Helligkeitsmessung von Kepler.png|All light curve data − December 2009 to May 2013, scan days 0066 to 1587 (''Kepler'')
File:KIC 8462852 - Helligkeitseinbruch 05. März 2011.png|5 March 2011 − day 792 <br /> 15% max dip (''Kepler'')
File:KIC 8462852 - Helligkeitseinbruch 28. Februar 2013.png|28 February 2013 − day 1519 <br /> 22% max dip (''Kepler'')
File:KIC 8462852 - Helligkeitseinbruch 17. April 2013.png|17 April 2013 − day 1568 <br /> 8% max dip (''Kepler'')
File:KIC 8462852 Daily Normalized Flux by Bruce Gary, 20170502-20180504.png|One year light curve −<br />up to 4 May 2018<br />([[Astronomy:Hereford Arizona Observatory|HAO]]<ref name="BG-20171114-latest">{{cite web |last=Gary |first=Bruce L. |title=Hereford Arizona Observatory photometry observations of KIC 8462852 |url=http://www.brucegary.net/ts5/ |date=14 November 2017 |work=BruceGary.net |access-date=24 December 2017 }}</ref><ref name="BG-20171004">{{cite web |last=Gary |first=Bruce L. |author-link=Bruce L. Gary |title=Hereford Arizona Observatory photometry observations of KIC 8462852 between 2 May and 4 October 2017 |url=http://www.brucegary.net/ts4/ |date=4 October 2017 |url-status=dead |archive-url=https://web.archive.org/web/20171004220716/http://www.brucegary.net/ts4/ |archive-date=4 October 2017 |work=BruceGary.net |access-date=23 December 2017 |quote='''Note:''' g'-band and r'-band dip depths (and shapes) may differ, with g'-band being more sensitive to dust cloud scattering due to its shorter wavelength (0.47 vs. 0.62 micron). For a reasonable particle size distribution (e.g., Hanson, 0.2 micron) the extinction cross section ratio would produce a depth at r'-band that is 0.57 x depth at g'-band. If g'-band depth is 0.3 %, for example, depth at r'-band could be 0.17 %. The "Tabby Team" measurements ([[:File:KIC 8462852 TS r-prime-band Normalized Flux by TabbyTeam, 20170502-20171004.png|Fig. 3]]) at r'-band are compatible with that small dip depth. Incidentally, none of these shapes resemble exo-comet tail transits (as described by Rappaport et al, 2017 [https://arxiv.org/abs/1708.06069 link]); so the mystery of what's producing these week-timescale dips continues! Actually, long oval shapes are known to produce V-shaped dips (think of rings with a high inclination).}}</ref><ref name="BG-20180101">{{cite web |last=Gary |first=Bruce L. |author-link=Bruce L. Gary |title=Hereford Arizona Observatory photometry observations of KIC 8462852 between 2 May and 31 December 2017 |url=http://www.brucegary.net/ts5/ |date=1 January 2018 |url-status=dead |archive-url=https://web.archive.org/web/20180102012647/http://www.brucegary.net/ts5/ |archive-date=2 January 2018 |work=BruceGary.net |access-date=1 January 2018 }}</ref><ref name="BG-20180504">{{cite web |last=Gary |first=Bruce L. |author-link=w:Bruce L. Gary |title=Hereford Arizona Observatory photometry observations of KIC 8462852 between 2 May 2017 and 4 May 2018 |url=http://www.brucegary.net/ts6/ |date=4 May 2018 |url-status=dead |archive-url=https://web.archive.org/web/20180505143701/http://www.brucegary.net/ts6/ |archive-date=5 May 2018 |work=BruceGary.net |access-date=5 May 2018 }}</ref><!---<br>''(<small>[http://www.brucegary.net/HAO/ HAO]=[[Astronomy:Hereford Arizona Observatory|HAO]]</small>)''--->)
File:KIC 8462852 October-December 2019 Gary.jpg|Light curve between 10 October 2019 and 11 January 2020 (HAO)<ref name="Gary_11Jan20">{{Cite web|url=http://www.brucegary.net/ts9/|date=11 January 2020|title=KIC 8462852 Hereford Arizona Observatory Photometry Observations #9|first=Bruce|last=Gary|access-date=5 April 2020|archive-url=https://web.archive.org/web/20200405060559/http://www.brucegary.net/ts9/|archive-date=5 April 2020}}</ref>
</gallery>

== See also ==
{{div col|colwidth=30em}}
* [[Astronomy:Dwarf planet#Former dwarf planets|Former dwarf planets]]
* [[Astronomy:Asteroid belt|Asteroid belt]]
* [[Astronomy:BD+20°307|BD+20°307]]
* [[Astronomy:Formation and evolution of the Solar System|Formation and evolution of the Solar System]]
* [[Astronomy:Giant-impact hypothesis|Giant-impact hypothesis]]
* [[Astronomy:Interstellar medium|Interstellar medium]]
* List of stars that have unusual dimming periods
* [[Astronomy:Nebular hypothesis|Nebular hypothesis]]
* [[Astronomy:Planetesimal|Planetesimal]]
* [[Astronomy:Protoplanetary disk|Protoplanetary disk]]
* [[Physics:Tidal force|Tidal force]]
* [[Astronomy:WD 0145+234|WD 0145+234]] (star disrupting an exoasteroid)
{{div col end}}

== References ==
{{reflist|30em}}

== Further reading ==
* {{cite book|author=Wallace Gary Ernst|title=The Dynamic Planet|url=https://archive.org/details/dynamicplanet0000erns|url-access=registration|page=[https://archive.org/details/dynamicplanet0000erns/page/18 18]|year=1990|publisher=Columbia University Press|isbn=978-0-231-07231-1}}
*  {{cite book|author=Michael M. Woolfson|title=The Origin and Evolution of the Solar System|url=https://books.google.com/books?id=KantSzMGPSkC&pg=PA316|year=2000|publisher=CRC Press|isbn=978-1-4200-3335-9}}

== External links ==
* [https://exoplanet.eu/catalog/wd_1145_017_b--2456/ NASA – WD 1145+017 b] at [[Astronomy:Extrasolar Planets Encyclopaedia|The Extrasolar Planets Encyclopaedia]].
* {{YouTube|gypAjPp6eps|title=Video (13:46) − "Tabby's Star"}}, a presentation by Tabetha S. Boyajian.
* {{YouTube|id=SVCpBr3fxdE|title=Video (31:00) − "Tabby's Star"}}, a presentation by Issac Arthur.
* {{YouTube|nf2oc6nMsn4|title=Video (01:00) − RZ Piscium}}, star with unusual light fluctuations (21 December 2017).
{{Exoplanet|state=collapsed}}

[[Category:Circumstellar disks|Circumstellar disks]]
[[Category:Hypothetical astronomical objects]]
[[Category:Planetary rings]]
[[Category:Unsolved problems in astronomy]]

{{Sourceattribution|Disrupted planet}}