'''Planet pengembara''' (dalam bahasa Inggris disebut: ''rogue planet''), adalahyang bendajuga langitdisebut sebesarsebagai planet yangmengambang mengorbitbebas pusat(''free-floating [[galaksi]]planet''/FFP) secaraatau langsung.objek Objekbermassa semacamplanet initerisolasi terlempar(''isolated dariplanetary-mass [[sistemobject''/IPMO), keplanetan]]adalah yangobjek menjadiantarbintang tempat terbentuknyabermassa [[planet]] ini, walaupun terdapat kemungkinan objek ini memangyang tidak pernahterikat mengitarisecara suatugravitasi pada [[bintang]] atau [[Katai coklat|katai cokelat]] manapun.<ref name="shostak">Shostak,{{Cite web|last=published|first=Seth (24 February Shostak|date=2005). ''-02-24|title=Orphan Planets: It's a Hard Knock Life''. [http|url=https://www.space.com/818-orphan-planets-hard-knock-life.html|website=Space.com], 24 February 2005. Retrieved on 5 February 2009 from http://www.space.com/searchforlife/seti_orphan_planets_050224.html.|language=en|access-date=2024-06-21}}</ref><ref name="lloyd">Lloyd,{{Cite Robin (18 April 2001)web|date=2008-10-13|title=SPACE.com -- ''Free-Floating Planets –-- British Team Restakes Dubious Claim''|url=https://web. Spacearchive.com, 18 April 2001. Retrieved on 5 February 2009 from org/web/20081013054054/http://www.space.com/scienceastronomy/astronomy/free_floaters_010403-1.html|website=web. {{Webarchivearchive.org|access-date=2024-06-21}}</ref><ref>Author unknown (18 April 2001). ''Orphan 'planet' findings challenged by new model''. [http://astrobiology.nasa.gov/ NASA Astrobiology], 18 April 2001. Retrieved on 5 February 2009 from {{Cite web|urldate=http://astrobiology.arc.nasa.gov/news/expandnews.cfm?id%3D7832009-03-22|title=ArchivedNASA copy- Astrobiology - Latest News|archive-url=https://web.archive.org/web/20090322091340/http://astrobiology.arc.nasa.gov/news/expandnews.cfm?id=783|archive-datewebsite=22 March 2009|dead-url=yesweb.archive.org|access-date=9 February 20092024-06-21}}</ref><ref>{{Cite [[Bimajournal|last=Kirkpatrick|first=J. SaktiDavy|Galaksilast2=Gelino|first2=Christopher BimaR.|last3=Faherty|first3=Jacqueline Sakti]]K.|last4=Meisner|first4=Aaron sendiriM.|last5=Caselden|first5=Dan|last6=Schneider|first6=Adam diperkirakanC.|last7=Marocco|first7=Federico|last8=Cayago|first8=Alfred memilikiJ.|last9=Smart|first9=R. miliaranL.|date=2021-02-23|title=The planetField pengembara.<ref>[[NeilSubstellar deGrasseMass Tyson]]Function inBased ''[[Cosmos:on Athe SpacetimeFull-sky Odyssey]]''20 aspc referredCensus toof by525 [httpL, T, and Y Dwarfs|url=https://phenomenaiopscience.nationalgeographiciop.comorg/2014article/03/1310.3847/a-guide-to-lonely-planets1538-in-the-galaxy4365/abd107|journal=The NationalAstrophysical Geographic]Journal Supplement Series|volume=253|issue=1|pages=7|doi=10.3847/1538-4365/abd107|issn=0067-0049}}</ref>
Planet-planet pengembara bisa jadi berasal dari sistem keplanetan tempat planet-planet tersebut terbentuk dan kemudian dilontarkan, atau bisa juga terbentuk dengan sendirinya di luar sistem keplanetan. [[Bima Sakti]] sendiri mungkin memiliki milyaran hingga triliunan planet pengembara, sebuah rentang yang mungkin bisa dipersempit oleh Teleskop Antariksa Nancy Grace Roman yang akan datang.<ref>{{Cite web|date=2014-03-13|title=A Guide to Lonely Planets in the Galaxy – Phenomena: No Place Like Home|url=https://web.archive.org/web/20140313190543/http://phenomena.nationalgeographic.com/2014/03/13/a-guide-to-lonely-planets-in-the-galaxy/|website=web.archive.org|access-date=2024-06-21}}</ref><ref>{{Cite web|last=Balzer|first=Ashley|last2=Center|first2=NASA’s Goddard Space Flight|date=2020-08-23|title=“Our Solar System May Be Unusual”: Rogue Planets Unveiled With NASA’s Roman Space Telescope|url=https://scitechdaily.com/our-solar-system-may-be-unusual-rogue-planets-unveiled-with-nasas-roman-space-telescope/|website=SciTechDaily|language=en-US|access-date=2024-06-21}}</ref>
Beberapa planet pengembara mungkin terbentuk dengan cara yang sama seperti bintang, dan [[Persatuan Astronomi Internasional]] mengusulkan agar objek semacam itu disebut "katai sub-cokelat".<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}}</ref> Contohnya adalah [[Cha 110913-773444]], yang mungkin terlempar dari sistem keplanetannya dan menjadi planet pengembara, atau terbentuk sendirian dan menjadi katai sub-cokelat.<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>
