Stars abe nomjikelo wobomi othatha izigidi ezimbalwa ukuya kwiitriliyoni zeminyaka. Bazalwa, batshintsha ngokuhamba kwexesha kwaye ekugqibeleni badibana nesiphelo sazo xa isibaso siphela ukuze sibe ngumzimba oxineneyo oshiyekileyo. Inkwenkwezi etshileyo inokuba a umnyama omhlophe okanye a inkwenkwezi ye-neutron okanye a Umngxunya omnyama kuxhomekeke kubunzima bokuqala benkwenkwezi.
Ubomi be Nkwenkwezi iqala ngobukhulu amafu e-interstellar yerhasi nothuli kwi Galaxy ngokudibana kweegesi ngenxa yobushushu obuphantsi ukuya kwiipokotho ezixineneyo. I-clumps iqokelela ngokuthe ngcembe into eninzi kwaye ikhule. Ngexesha elithile, i-clumps iyawa ngenxa yokwanda kwamandla omxhuzulane. Ukungqubuzana ngexesha lokuwa kutshisa umcimbi kwaye inkwenkwezi yomntwana iyazalwa. Yi le isigaba seprotostar kumjikelo wobomi beenkwenkwezi.
Ukuwa phantsi komxhuzulane kuyaqhubeka. Ngenxa yoko, ubushushu kunye noxinzelelo kumbindi luyaqhubeka nokwakha. Emva kwezigidi zeminyaka, ubushushu kunye noxinzelelo kumbindi weprotostar ziye ziphakame ngokwaneleyo ukuvumela iinuclei zehydrogen ukuba zihlangane. Umdibaniso weNyukliya ukhulula isixa esikhulu samandla esitshisa umcimbi ngokwaneleyo ukunqanda ukuwohloka ngakumbi phantsi komxhuzulane. Eli nqanaba xa udibaniso lwenyukliya lusenzeka ngokuzinzileyo (kwaye amandla akhutshiweyo afudumeza ngokwaneleyo umcimbi ukuthintela ukuwa komxhuzulane) lelona nqanaba liphambili kunye nelona nqanaba lide kubomi benkwenkwezi. Iinkwenkwezi kweli nqanaba zibizwa ngokuba 'ziiinkwenkwezi eziphambili zolandelelwano' kwaye iqonga libizwa ngokuba '.inqanaba eliphambili lolandelelwano'. IHydrojeni lelona futhe liphambili lenkwenkwezi. Izinga lokusetyenziswa kwamafutha lixhomekeke kubunzima benkwenkwezi. Inkwenkwezi enkulu iya kusebenzisa amafutha ngesantya esiphezulu ukukhulula amandla awoneleyo ukunqanda ukuwa kwayo phantsi komxhuzulane.
Xa amafutha ephela, udibaniso lwenyukliya luyayeka kwaye akukho mandla okufudumeza imathiriyeli ukulinganisa amandla omxhuzulane kwaye undoqo uwe phantsi komxhuzulane, ushiya ngasemva intsalela ehlangeneyo. Esi sisiphelo senkwenkwezi. Inkwenkwezi efileyo iba nokuba mhlophe qhwa okanye neutron star okanye Umngxunya omnyama kuxhomekeke kubunzima benkwenkwezi yokuqala.
Xa ubunzima benkwenkwezi yantlandlolo bungaphantsi kobunzima obuphindwe ka-8 belanga (<8 M⦿), iba a umnyama omhlophe. Inkwenkwezi efileyo iba yinkwenkwezi ye-neutron, xa ubunzima beenkwenkwezi yasekuqaleni buphakathi kwe-8 ukuya kwi-20 ubunzima belanga (8 M.⦿ < M <20 M⦿) ngelixa iinkwenkwezi zinobunzima obungaphezu kwama-20 ubukhulu belanga (>20 M⦿) ibe imingxunya emnyama xa amafutha ephela.
I-Brown Dwarfs (BDs)
Stars ukufikelela 'kwinqanaba lokudityaniswa kwenyukliya' okanye 'inqanaba eliphambili lolandelelwano' kumjikelo wobomi babo. Kuthekani ukuba into esesibhakabhakeni ibumba njengenkwenkwezi kodwa ingafikeleli kweli nqanaba?
Iintsana eziBrown ziqala njengenkwenkwezi, zixinene ngokwaneleyo ukuba ziwele phantsi komxhuzulane kodwa ingundoqo yazo ayinakuze ixinene ngokwaneleyo kwaye ishushu ukuze iqalise ukudityaniswa kwenyukliya ngenxa yoko ingaze ibe yinkwenkwezi yokwenyani. Ezi zinto ziyafana kwiimpawu kuzo zombini iinkwenkwezi kunye maplanethi.
Iincinci ezimnyama zincinci kuneenkwenkwezi kodwa zinkulu kakhulu kunezo maplanethi. Ezinye ezincinci zithelekiseka ngobungakanani maplanethi. Elona lincinane laziwayo lilingana neJupiter ngokuphindwe kasixhenxe.
Iincinci ezimnyama zibalulekile kumzekelo wokwenziwa kweenkwenkwezi kumafu aphakathi kweenkwenkwezi kunye nothuli. Iinzame ziyenziwa ukufumanisa eyona mizimba mincinci ibumba ngendlela efana nenkwenkwezi.
Eyona incinci iBrown Dwarf
Kutshanje, abaphandi baye benza uhlolisiso kumbindi weqela elenza iinkwenkwezi IC 348 ekumgama omalunga ne-1,000 XNUMX leminyaka yokukhanya besebenzisa UJames Webb Space Telescope (JWST). Ngokusekwe kwiphotometry yezinto, iqela lichonge abagqatswa abathathu abamnyama. Enye yazo iphindwe kathathu ukuya kwezine ubunzima beJupiter nto leyo eyenza ibe yeyona mnyama incinci incinci eyaziwayo ukuza kuthi ga ngoku.
Umnyama omnyama ophindwe kathathu ubunzima beJupiter unokuba mncinci ngokuphindwe ngama-300 ilanga. Ukuba umngxuma omncinane omnyama unokwakheka ngendlela efana nenkwenkwezi kunzima ukuyichaza kuba ilifu elincinane eliphakathi kweenkwenkwezi ngokuqhelekileyo alinakuba liwe libangele ukuba kuvele umntu omnyama ngenxa yomxhuzulane obuthathaka. Ke, incinci emnyama emnyama enjalo ibeka umngeni phambi kweemodeli zangoku zokwenza iinkwenkwezi.
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Iingxelo:
- uLuhman KL, okqhubekayo 2023. Uvavanyo lwe-JWST lwePlanethi yeMass Brown Dwarfs kwi-IC 348. I-Astronomical Journal, uMqulu 167, iNombolo 1. Ipapashwe nge-13 kaDisemba 2023. DOI: https://doi.org/10.3847/1538-3881/ad00b7
- IWebb yeNASA ichonga eyona nto incinci iBrown Dwarf edadayo. Ithunyelwe nge-13 kuDisemba 2023. Iyafumaneka e https://www.nasa.gov/missions/webb/nasas-webb-identifies-tiniest-free-floating-brown-dwarf/
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