Izazi zezinkanyezi zilinganisela ukuthi cishe kunezimbobo ezimnyama ezingaba izigidi eziyi-100 ezizulazula ezinkanyezini emthaleni wethu, kodwa kuze kube manje azikahlonzi nowodwa umgodi omnyama. Nokho, ngemva kweminyaka eyisithupha yokuhlolisisa ngokucophelela, i-Hubble Space Telescope inikeze ubufakazi bokuqala obuqondile bembobo eyodwa emnyama etshuza emkhathini ophakathi kwezinkanyezi ngokulinganisa ngokunembile ubukhulu bento eyi-phantom. Kumayelana a umgodi omnyama eMilky Way.
Kulesi sihloko sizokutshela ngezici, imvelaphi nokunye okuningi mayelana nomgodi omnyama ku-Milky Way.
yini imbobo emnyama
Okokuqala, kufanele wazi kahle ukuthi umgodi omnyama uyini njengoba kunezinganekwane eziningi ngawo. Imbobo emnyama isenzakalo sezinkanyezi esivela lapho inkanyezi enkulu iwa ngaphansi kwethonya lamandla ayo adonsela phansi. okunikeza indawo yesikhala esinokuminyana okuphezulu ngokumangalisayo namandla adonsela phansi anamandla amakhulu. Ngaphansi kwalezi zimo, i-matter icindezelwa ngendlela yokuthi umthamo wayo wehliselwe ku-zero, okudala ubunye, iphuzu lokuminyana okungapheli phakathi nendawo yomgodi omnyama.
Isici esihlukanisayo sembobo emnyama wumkhathizwe wayo womcimbi, okuwumngcele ocatshangelwayo owuzungezile ngale kwalokho ukukhanya nanoma yini enye engakwazi ukuphuma. Lokhu kusho ukuthi noma iyiphi into ewela lo mngcele izovaleleka ngokungenathemba ngaphakathi kwembobo emnyama, inikeze ukubonakala "kwembobo" emkhathini.
Izimbobo ezimnyama azibonakali ngokuqondile, njengoba zingakhiphi ukukhanya, kodwa ukuba khona kwazo kungachazwa ngemiphumela yazo endabeni ezungezile.
Imbobo emnyama ku-Milky Way
Kuze kube manje, zonke izimbobo ezimnyama seziqondiswe ngokwezibalo noma ngokusebenzisana kwezinhlelo zezinkanyezi ezimbaxambili noma i-galactic nuclei, okwenza lokhu kutholwe okukhethekile kakhulu.
Imbobo emnyama esanda kutholwa isendaweni engaba ngu-5.000 light-year kude ku-Carina-Sagittarius spiral arm of the Milky Way galaxy. Kodwa-ke, abakutholile kuvumele izazi zezinkanyezi ukuthi zilinganisele ukuthi imbobo emnyama eseduze kakhulu ye-stellar-mass black eMhlabeni ingase iqhele ngama-light-year angama-80, okucishe kufane uma kucatshangelwa ukuthi inkanyezi eseduze kakhulu nesistimu yethu sonozungezilanga, i-Proxima Centauri, isanda kuqeda. Iminyaka emi-4 elula. Izimbobo ezimnyama ze-stellar-mass zivame ukuhlangana nezinkanyezi ezihambisana nazo, okwenza lokhu kube okungavamile.
Izimbobo ezimnyama ku-Milky Way bazalwa ezinkanyezini eziyimidondoshiya okungenani izikhathi ezingu-20 ubukhulu beLanga, akha ingxenye engaphansi kwenkulungwane yenani lezinkanyezi eziku-Milky Way. Lezi zinkanyezi ziqhuma njengama-supernovae, ama-cores azo agaywa amandla adonsela phansi futhi abe yimigodi emnyama. Njengoba ukuziqhuma kungalingani ngokuphelele, le mbobo emnyama ingase iqale futhi idubule phakathi komthala wethu, ibe umgodi omnyama ozulazulayo.
Ukutholwa kwezimbobo ezimnyama
Izibonakude azikwazi ukuthwebula imbobo emnyama enhlanhlathayo ngoba ayikhiphi ukukhanya. Nokho, imbobo emnyama ijika isikhala, bese igoba futhi ikhulise ukukhanya okuvela enkanyezini, nanoma yini engemuva kwayo okwesikhashana.
Ngakho-ke, ukuze kutholwe izimbobo ezimnyama, izibonakude ezisekelwe phansi ziqapha ukukhanya kwezigidi zezinkanyezi ezindaweni zezinkanyezi ezinothile futhi zibheke endaweni emaphakathi ye-Milky Way, zibheke ukukhanya okungazelelwe, okuveza izimbobo ezinkulu ezimnyama. Izinto zidlula phakathi kwethu nezinkanyezi.
Ukuhlanekezelwa kwesikhala okubangelwa amandla adonsela phansi ento engaphambili edlula phambi kwenkanyezi ekude kuyagoba okwesikhashana futhi kukhulise ukukhanya okuvela kunkanyezi engemuva njengoba idlula phambi kwayo. Izazi zezinkanyezi zisebenzisa lesi simo, esibizwa ngokuthi i-gravitational microlensing, ukufunda izinkanyezi nama-exoplanets. Kodwa isignesha yembobo emnyama engaphambili ihlukile kwezinye izehlakalo ze-microlensing.
Amandla adonsela phansi omgodi omnyama azonweba ubude besikhathi somphumela welensi ngezinsuku ezingaphezu kwama-200.. Futhi, uma into emaphakathi iyinkanyezi engaphambili, ingabangela ukushintsha kombala kafushane ekukhanyeni kwenkanyezi okulinganisiwe ngenxa yokuthi ukukhanya okuvela ngaphambili nezinkanyezi ezingemuva kuyahlangana okwesikhashana. Kodwa azikho izinguquko zombala ezabonwa ngesikhathi semicimbi ye-gravitional microlening.
UHubble wabe esesetshenziselwa ukukala ubukhulu, ibanga, nesivinini somgodi omnyama. Lokho kuholele ithimba le-Kailash Sahu e-Space Telescope Science Institute e-Baltimore, eMaryland, ukuba lilinganisele isisindo salo cishe ngesisindo selanga esiyisikhombisa.
Enye incazelo yembobo emnyama ku-Milky Way
Ngakolunye uhlangothi, elinye ithimba lezazi zezinkanyezi eliholwa nguCasey Lam waseNyuvesi yaseCalifornia, eBerkeley, naye owafunda lesi sigameko, labika izilinganiso eziphansi kancane zobunzima bayo, okusho ukuthi into ingaba imbobo emnyama noma inkanyezi ye-neutron. , ngakho yebo bayakwenza. Angazi ukuthi kungenzeka okwesibili.
Ngakho-ke, bayalinganisa lokho ubukhulu bento ehlangene engabonakali buphakathi kuka-1,6 no-4,4 izikhathi zobunzima beLanga. Ekupheleni kobubanzi, into izoba yimbobo emnyama; ekugcineni okuphezulu kobubanzi, into izoba imbobo emnyama; ekugcineni kobubanzi, into izoba yimbobo emnyama. Emaphethelweni aphansi, kuzoba inkanyezi ye-neutron.
Nakuba kunezimbobo ezimnyama ezingazodwa ezilinganiselwa ezigidini eziyikhulu ezizulazula emthaleni wethu, kwizazi zezinkanyezi ze-Hubble, ukuthola ngisho nokuncane okuncane nje kokukodwa kufana nokubheka inaliti esigxotsheni sotshani.
“Njengoba sifuna ukusho ukuthi nakanjani imbobo emnyama, kufanele sicabangele zonke izindlela. Lokhu kuhlanganisa izimbobo ezincane ezimnyama futhi mhlawumbe nezinkanyezi ze-neutron," kuchaza uJessica Lu weqembu laseBerkeley. "Kodwa noma yini, le nto iyinsali yokuqala yenkanyezi emnyama etholakala ku-Milky Way ngaphandle kwenkampani enye inkanyeziURam wengeza.
Ukuthola izilinganiso kwakuwumsebenzi onzima kuwo womabili amaqembu ngoba enye inkanyezi ekhanya kakhulu yayiseduze kakhulu nento ebhekiwe. “Kufana nokuzama ukulinganisa ukunyakaza kukakhanyikhanyi eduze kwelambu elikhanyayo,” kusho uSahu. "Kudingeke ukuthi sisuse ngokucophelela ukukhanya ezinkanyezini ezikhanyayo eziseduze ukuze silinganise ngokunembile ukuchezuka emthonjeni omncane."
Ithimba likaSahu lilinganisela lokho umgodi omnyama ongasodwa uhamba eMilky Way ngamamayela ayi-100.000 ngehora, ngokushesha ngokwanele ukuhamba usuka eMhlabeni uye eNyangeni ngaphansi kwamahora amathathu. Lokho kushesha kunezinye izinkanyezi eziningi eziseduze kulesi sifunda somthala wethu.
Ngithemba ukuthi ngalolu lwazi ungafunda kabanzi mayelana nomgodi omnyama ku-Milky Way wathola izici zayo.