IDAN BETELGEUSE TA HAƊIYE ABOKIN TAFIYARTA, SARARIN SAMA ZAI YI WALƘIYA

Betelgeuse, babban tauraro ja mai girman gaske (red supergiant) da ke nuna kafaɗar Orion, tana ɗaya daga cikin taurarin da aka fi nazari a sararin sama, kuma radius ɗinta ya kusa ninki 800 na na Rana. Shekaru da dama, masana falaki sun yi ta muhawara kan ko tana ɓoye abokin tafiya: saurinta a kan layin ganinmu yana girgiza ta hanya mai ban mamaki, haskenta yana da wani dogon zagaye na biyu, kuma tana juyawa da sauri fiye da yadda ake tsammani.

Bincike na baya-bayan nan sun bayyana dukan ukun da ƙaramin tauraro mara nauyi sosai abokin tafiya (low-mass companion star) da ke kewayawa a cikin faɗaɗɗen sararin waje (outer atmosphere) na Betelgeuse, sau ɗaya a kowace shekara shida ko makamancin haka, a nisan kusan ninki 8.6 na nisan Duniya zuwa Rana. Yanzu yana da suna: α Orionis B, ko Siwarha, wato “munduwarta” a Larabci. Na’urorin hangen nesa biyu mai yiwuwa sun hango shi kai tsaye, ko da yake ganin har yanzu ba shi da cikakken tabbas, kuma ƙiyasin nauyinsa ya dogara ne da samfurori (models).

Abokin tafiya a kan karkacewar mutuwa a hankali

Wannan kewaya ba ta daidaitu ba. Ƙarfin janyewa (tides) a cikin babbar rigar waje (envelope) ta Betelgeuse mai tafasa yana musayar juyawa da kewayar kuma yana sa ta ragu. A halin da ake ciki, babban tauraron yana ci gaba da kumbura. Daga ƙarshe samansa ya kai ga abokin tafiyar, kuma ƙaramin tauraron ya haɗiyu. Masana falaki suna kiran matakin da ke biyo baya rigar bai ɗaya (common envelope): taurari biyu suna raba jiki ɗaya na iskar gas.

Irin waɗannan haɗiyewa suna haifar da wani sanannen nau’in fashewa, jan nova mai haske (luminous red nova). Damin taurarinmu (Galaxy) yana samar da kusan guda ɗaya a kowace shekara goma, amma yawancinsu suna faruwa a nesa sosai kuma ana ganinsu ne kawai bayan sun fashe. Betelgeuse za ta zama abu mai wuyar samu: tauraro na kusa, wanda aka auna da kyau, da aka kama kafin lamarin.

Naunet Leonhardes-Barboza da abokan aikinta a University of California, Santa Cruz, Center for Computational Astrophysics na Flatiron Institute a New York da Center for Astrophysics | Harvard & Smithsonian sun bi juyin rayuwar Betelgeuse tare da abokan tafiya masu nauyin Rana 0.7, 1.0 da 2.0 — don rufe nauyin na gaske wanda ba shi da tabbas — har zuwa lokacin haɗiyewa. Gwargwadon nauyin, wannan lokaci yana zuwa nan da shekaru 7,262, 5,702 ko 4,293 a cikin samfurorinsu. Marubutan suna ɗaukar waɗannan kwanakin a matsayin girman kima (orders of magnitude) kawai: yadda ƙarfin janyewa ke aiki a cikin rigar da ke hargitsi yana da rashin tabbas na ninki goma ko fiye.

Tarwatsewa kusa da tsakiya

Da zarar an haɗiye shi, abokin tafiyar yana karkacewa zuwa ciki da sauri fiye da kullum, yana zubar da kuzarin kewayarsa cikin iskar gas, har sai nauyin janyewa (gravity) na babban tauraron ya yayyage shi a nisan ’yan radius na Rana daga tsakiya. A cikin misalai biyu mafiya sauƙin nauyi, abokin tafiyar har yanzu matashin tauraro ne, bai riga ya shiga babban matakinsa mai daidaito ba, kuma yana da rigar waje mai kumburi mara yawan nauyi (low-density); wanda ke da nauyin Rana 2 ya fi matsewa.

Ƙungiyar ta ciyar da wannan kuzari cikin kwaikwayon fuska ɗaya (one-dimensional) na iskar gas da haske (radiation), waɗanda ke ɗaukar tauraron a matsayin cikakken zagaye kuma suna bin abin da ke canzawa gwargwadon nisa daga tsakiya kawai. Gaba ɗaya, 6.3 zuwa 13.9 × 10⁴⁸ ergs (erg ƙaramin ma’aunin kuzari ne) ne ake saki can cikin zurfi, ƙarƙashin gindin rigar hydrogen mai tafasa ta tauraron, inda iskar gas mai zafi ke hawa sama tana sauka kamar ruwan da ke tafasa — zurfi da yawa da haske ba zai iya fita nan take ba. Maimakon haka, kuzarin yana tura igiyar matsi (pressure wave) wadda ke ƙara tsananta har ta zama girgiza (shock) kuma tana tafiya waje daga ’yan radius na Rana zuwa saman, kusan radius na Rana 820 daga tsakiya. A samfurin nauyin Rana 1.0, tana ɗaukar kusan kwanaki 28 kafin ta kai saman.

Ta fi Venus haske, ta fi Sirius shuɗi

Lokacin da girgizar ta fito waje, Betelgeuse tana walƙiya. Ƙolin yana kaiwa 2.4 zuwa 6.2 × 10⁴¹ ergs a kowace daƙiƙa — kusan ninki miliyan ɗari na hasken da Rana ke fitarwa (figure 4 tana zana shi kusa da hasken Rana 10⁸), kusan ninki 600 zuwa 1,600 na hasken Betelgeuse kanta a yau. Lokacin haske gajere ne: kwanaki 1.5 zuwa 2, ana ƙirga shi tsakanin lokutan da take haskakawa da rabin ƙolinta.

Walƙiyar da aka yi hasashe ga abokan tafiya masu nauyin Rana 0.7, 1.0 da 2.0, a daidaita da ƙolin. Layukan cikakku sun haɗa da nauyi da kuzarin abokin tafiyar da aka yayyage; layukan ɗigo-ɗigo suna ƙirga kuzarin karkacewar zuwa ciki kawai. — Figure 4, Leonhardes-Barboza et al. (2026), arXiv:2610.31755.

Idan aka gani daga Duniya, in ji marubutan, fashewar za ta fi Venus haske sau da dama, yayin da take ƙasa da hasken cikakken wata, kuma za ta zarce Sirius nesa ba kusa ba, tauraron da ya fi haske a sararin daren yau. Launinta zai canza sosai: ja yayin da girgizar ke binne a ciki, sannan farat ɗaya ta fi Sirius shuɗi lokacin da iskar gas mai zafi ta kai saman, sannan ta sake yin ja yayin da iskar gas da aka fitar ke faɗaɗa kuma tana yin sanyi.

Hagu: samfurorin Betelgeuse (taurari masu launi) suna cikin ƙoli na farko mafiya haske kuma mafiya gajarta na jajayen novae da aka lura da su. Dama: hanyar da aka yi hasashe ta samfurin nauyin Rana 1.0 a sararin dare, idan aka kwatanta da Wata, Venus, Jupiter da taurari masu haske; ma’aunin launi yana ƙirga kwanaki daga ƙolin. — Figure 5, Leonhardes-Barboza et al. (2026), arXiv:2610.31755.

Walƙiya da ke tuna wanda aka haɗiye

Gwargwadon nauyin abokin tafiya, gwargwadon hasken walƙiyar: hasken ƙoli yana ƙaruwa kusan kamar nauyin abokin tafiyar zuwa ƙarfin 0.93, bambanci na kusan ninki 2.5 tsakanin samfuri mafi sauƙi da mafi nauyi. Tsawon lokacin kusan bai motsa ba, da kusan 35%. Don haka walƙiyar shuɗi ta farko tana ɗauke da tunawa mai aunuwa na tauraron da aka haɗiye.

Yayyage abokin tafiyar ma yana da muhimmanci. Yana ƙara kuzari, amma kuma yana ƙara nauyi ga iskar gas da aka fitar, don haka kowane gram yana samun ƙarancin kuzari: a cikin kwaikwayon, haɗa shi yana ɗan rage ƙolin idan aka kwatanta da kuzarin karkacewar zuwa ciki kaɗai.

Iskar gas daidai da Rana shida zuwa goma sha ɗaya

Haɗewar kuma tana hura iskar gas mai yawan hydrogen mai nauyin Rana 6.15 zuwa 11.19 a gudun kusan kilomita 200 a kowace daƙiƙa — babban kaso na rigar waje ta Betelgeuse. Wata sananniyar dabarar lissafin kuzari (energy budget) ta ce abokin tafiya mafi sauƙi bai kamata ya fitar da komai ba; duk da haka kwaikwayon yana jefar da fiye da nauyin Rana shida, saboda girgizar tana tura yadudduka na waje ta hanyoyin da irin wannan lissafi ba ya gani.

Ana sa ran Betelgeuse za ta ƙare a matsayin supernova, mai yiwuwa cikin shekaru 100,000 masu zuwa. Idan haɗewar ta riga ta, wannan fashewa za ta tashi ne a cikin iskar gas da haɗewar ta bari a baya.

Tsohon tabo, ƙura da iskar gas mara daidaito

Ba kowa ne ke fassara tarihin Betelgeuse iri ɗaya ba. Wasu masu bincike suna ganin saurin juyawarta da baƙon haɗin sinadaran samanta a matsayin alamun wata haɗewa ta baya, maimakon alamun abokin tafiya. Idan fassarorin biyu duka gaskiya ne, Betelgeuse za ta buƙaci tarihi mafi rikitarwa, mai yiwuwa a cikin tsarin taurari da dama; marubutan sun tsaya kan ma’auratan Betelgeuse da Siwarha.

Samfurin kuma na fuska ɗaya ne, alhali haɗewa ta gaske ba ta da daidaito kuma tana da hargitsi, kuma bai kula da iskar gas da ƙurar da Betelgeuse ta riga ta zubar ba. Karo da wannan abu zai faɗaɗa walƙiyar kuma ya dusashe ƙolinta, don haka hasken da aka yi hasashe kusan iyakar sama ce (upper limit), tsawon lokutan kuma iyakar ƙasa. Ƙura mai kauri za ta iya sa fashewar ta yi ja kuma ta dusashe a hasken da ido ke gani, tana haskakawa a infrared maimakon haka. Amma bisa wani ƙiyasin baya da marubutan suka ambata, ƙurar za ta bar walƙiyar da ɗan ja kawai, ba tare da ɓoye ta ba.