ƘURA MAI KAMAR GILASHI TA TAURARO MAI WUTSIYA NA TSAKANIN TAURARI

Abubuwan tsakanin taurari (interstellar objects) ƙananan jikuna ne da aka haifa a wasu tsarin duniyoyi, ƙarƙashin wasu yanayi na sinadarai da na zahiri. Idan ɗaya ya ratsa Tsarin Rana (Solar System), yana kawo kaya daga wani wuri kusa sosai yadda za a iya nazarinsa dalla-dalla. 3I/ATLAS shi ne na uku da aka rubuta, bayan 1I/’Oumuamua a 2017 da 2I/Borisov a 2019.

Nazarce-nazarce da dama tuni sun gano cewa 3I/ATLAS bai yi kama da taurarinmu masu wutsiya ba: gwargwadon isotopes da ba a saba gani ba — nau’o’in atom ɗaya masu nauyi da marasa nauyi — na hydrogen, carbon da nitrogen a cikin iskar gas ɗinsa, da carbon dioxide mai yawa. Tare, waɗannan suna nuna haihuwa a kelvin 30 ko sanyi fiye da haka, a wani muhalli da ba shi da yawan sinadarai masu nauyi (heavy elements) sosai. Waɗannan alamu ne daga iskar gas ɗinsa. Cristina Thomas, ta Northern Arizona University, da abokan aikinta daga NASA, ESA da jami’o’i da dama sun duba abin da aka yi shi da shi a sigar ƙaƙƙarfa: ƙurarsa.

Bakan haske (spectrum) mai wahala

A ranar 16 ga Disamba 2025, bayan ya fi kusantar Rana, tauraron mai wutsiya yana nesa da Rana ninki 2.21 na tazarar Duniya da Rana. Na’urar hangen nesa ta sararin samaniya James Webb (James Webb Space Telescope) ta naɗi haskensa tsakanin micrometre 5 da 14 (kashi ɗaya cikin dubu na milimita) da na’urarta ta tsakiyar infrared, MIRI, na kusan minti bakwai da rabi.

Tauraron mai wutsiya ba ɗigo ba ne kuma ba faffaɗan tabo ba: cibiya (nucleus) naɗe a cikin gajimaren ƙura mara kaifi. Sarrafa bayanai da aka saba yi wa abubuwa masu faɗi ya bar wani tsari mai haƙora kamar zarto tsakanin micrometre 10 da 12, daidai inda muhimmiyar alamar take. Ƙungiyar ta sake gina bakan hasken kamar tushen haske guda (point source), da gyara don hasken ƙurar da ke kewaye.

Kumburi mai santsi

Idan Rana ta ɗumama ƙura, zuwa kusan kelvin 198 a nan, tana haskakawa a hasken infrared. Silicates — ma’adinan da ke samar da mafi yawan duwatsu — suna ƙara kumburi kusa da micrometre 10, wanda girgizar haɗin silicon da oxygen (silicon–oxygen bonds) ke haifarwa. Siffarsa tana nuna waɗanne ma’adinai ne ke nan.

A 3I/ATLAS kumburin faɗi ne kuma santsi. A taurari masu wutsiya na Tsarin Rana, yana ci gaba da kasancewa a sama zuwa gaba. A wasu, kamar 17P/Holmes, yana ɗauke da ƙololuwa a micrometre 9.95 da 11.15: alamun lu’ulu’u na olivine mai yawan magnesium.

Ratsin silicate na micrometre 10 na 3I/ATLAS (shuɗi mai haske) idan aka kwatanta da taurari masu wutsiya na Tsarin Rana: ratsin 3I yana sauka da wuri kuma cikin santsi. — Figure 2, Thomas et al. (2026), arXiv:2610.37540.

Ƙirga lu’ulu’u da ba sa nan

Ƙungiyar ta kwaikwayi ƙurar a matsayin cakuɗin abubuwa uku: carbon mara tsari (amorphous carbon) da nau’i biyu na silicate mara tsari (amorphous silicate), nau’in olivine da nau’in pyroxene. Amorphous yana nufin rashin tsari a matakin atom, kamar gilashi, maimakon jeruwa da kyau kamar lu’ulu’u.

Sai aka riƙa ƙara lu’ulu’u kaɗan-kaɗan, har dacewar ta lalace a fili. Mafi kyawun dacewa koyaushe ba ta da lu’ulu’u ko ɗaya. Iyakar sama ita ce 5.3% na hasken da silicate ke fitarwa; wata ƙungiya, ta amfani da wani yanayin aiki na Webb daban, ta sanya ta a 3.1% bisa nauyi (by mass).

Dacewar kuma tana fifita pyroxene da kusan 180 zuwa 1 a kan olivine — ko da yake ɗayan ƙungiyar ta Webb, da nata samfurin ƙura, ta sami galibin ƙwayoyi irin na olivine — a cikin ƙwayoyi masu matsatsu ƙasa da micrometre ɗaya. Ƙololuwa ta biyu kusa da micrometre 6.83 tana dacewa da abubuwa na halitta (organic matter) masu yawan haɗin carbon da hydrogen, ko ma’adinan carbonate; waɗannan bayanai ba za su iya bambance wanne ba.

Wurin haihuwa mai sanyi da natsuwa

Silicates masu lu’ulu’u a taurari masu wutsiya alama ce ta ƙurar da ta taɓa yin zafi sosai. Rashinsu yana nufin ƙurar 3I/ATLAS ta ga zafi kaɗan ƙwarai, daidai da iskar gas ɗinsa. A cewar marubutan, mai yiwuwa ta samu ne a wani ɓangare mai natsuwa na faifan (disc) da ke kewaye da tauraronta, da ƙaramin cakuɗuwa. Taurari masu wutsiya na Tsarin Ranarmu kuwa, sun karɓi wata ƙura da aka gasa kusa da Rana a ƙuruciyarta.

Wani abin mamaki ya rage. Ana tunanin ƙurar da ke tsakanin taurari galibi nau’in olivine ce, amma a dacewar wannan ƙungiyar, 3I/ATLAS, kamar taurarinmu masu wutsiya, yana da yawan pyroxene: wani tsari da ba a sani ba zai iya canza ƙurar a wani wuri a kan hanya.

Sabuwar ƙura daga zurfi

Hasken sararin samaniya (cosmic rays) daga damin taurari (galaxy) zai iya, a ka’ida, mayar da lu’ulu’u gilashi, amma a yadudduka na waje na jiki kawai. Marubutan sun lura cewa mai yiwuwa 3I/ATLAS ya rasa mita 10 ko fiye na samansa yayin ratsawarsa ta Tsarin Rana. Saboda haka ƙurar da Webb ya gani bayan wannan wucewa na iya fitowa daga yadudduka masu zurfi, waɗanda ba a canza su sosai ba — kusa da abin da aka yi wannan tauraro mai wutsiya da shi lokacin da ya samu.