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Asteroids masu canzawa da wadataccen abu na halitta, ƙwayoyin C-type na iya zama ɗaya daga cikin manyan hanyoyin ruwa a Duniya. A halin yanzu, chondrites masu ɗauke da carbon suna ba da mafi kyawun ra'ayi game da sinadaran da suke da shi, amma bayanai game da meteorites sun gurɓata: nau'ikan da suka fi ɗorewa ne kawai ke tsira daga shiga sararin samaniya sannan su yi mu'amala da muhallin duniya. A nan mun gabatar da sakamakon cikakken bincike mai girma da na microanalytical na babban ƙwayar Ryugu da jirgin sama na Hayabusa-2 ya kawo wa Duniya. Ƙwayoyin Ryugu suna nuna kusanci a cikin abun da ke ciki da chondrites marasa rarrabuwa amma waɗanda aka canza su da ruwa, waɗanda ake amfani da su sosai a matsayin alamar cikakken abun da ke cikin tsarin hasken rana. Wannan samfurin yana nuna alaƙar sarari mai rikitarwa tsakanin ƙwayoyin aliphatic masu arziki da silicates masu layi kuma yana nuna matsakaicin zafin jiki na kusan 30 °C yayin zaizayar ruwa. Mun sami yalwar deuterium da diazonium daidai da asalin hasken rana. Ƙwayoyin Ryugu sune kayan da ba a taɓa yin nazari a kansu ba kuma ba a iya raba su ba kuma sun fi dacewa da abun da ke cikin tsarin hasken rana.
Daga watan Yunin 2018 zuwa Nuwamba 2019, jirgin sama mai suna Hayabusa2 na Hukumar Binciken Sararin Samaniya ta Japan (JAXA) ya gudanar da wani bincike mai zurfi na sararin samaniyar Ryugu. Bayanai daga Near Infrared Spectrometer (NIRS3) a Hayabusa-2 sun nuna cewa Ryugu na iya ƙunshe da wani abu mai kama da chondrites na carbonaceous mai zafi da/ko shock-metamorphic. Mafi kusanci shine CY chondrite (nau'in Yamato) 2. Ana iya bayanin ƙarancin albedo na Ryugu ta hanyar kasancewar adadi mai yawa na abubuwan da ke da wadataccen carbon, da kuma girman barbashi, porosity, da tasirin yanayi na sarari. Jirgin sama mai suna Hayabusa-2 ya yi saukar jiragen sama biyu da tattara samfura akan Ryuga. A lokacin saukar jiragen sama na farko a ranar 21 ga Fabrairu, 2019, an samo kayan saman, wanda aka adana a cikin sashe na A na kwalin dawowa, kuma a lokacin saukar jiragen sama na biyu a ranar 11 ga Yuli, 2019, an tattara kayan kusa da wani ramin wucin gadi da wani ƙaramin mai ɗaukar hoto ya samar. Ana adana waɗannan samfuran a Ward C. Halayen farko na barbashi marasa lalatawa a Mataki na 1 a cikin ɗakuna na musamman, marasa gurɓatawa da tsarkakakkun nitrogen a wuraren da JAXA ke sarrafawa sun nuna cewa barbashi na Ryugu sun fi kama da chondrites na CI4 kuma sun nuna "matakan bambance-bambance daban-daban"3. Rarraba Ryugu da alama ta saba wa juna, kamar CY ko CI chondrites, za a iya warware ta ne kawai ta hanyar cikakken bayanin isotopic, elemental, da mineralological na barbashi na Ryugu. Sakamakon da aka gabatar a nan yana ba da tushe mai ƙarfi don tantance wanne daga cikin waɗannan bayanai na farko guda biyu don cikakken abun da ke cikin asteroid Ryugu ya fi yiwuwa.
An tura ƙwayoyin Ryugu guda takwas (kimanin 60mg jimilla), huɗu daga Chamber A da huɗu daga Chamber C, zuwa Mataki na 2 don kula da ƙungiyar Kochi. Babban burin binciken shine a bayyana yanayi, asali da tarihin juyin halittar asteroid Ryugu, da kuma yin rikodin kamanceceniya da bambance-bambance da sauran samfuran waje kamar chondrites, ƙwayoyin ƙurar da ke tsakanin duniya (IDPs) da kuma taurari masu dawowa. Samfuran da aka tattara ta hanyar aikin Stardust na NASA.
Cikakken bincike na ma'adanai na hatsi biyar na Ryugu (A0029, A0037, C0009, C0014 da C0068) ya nuna cewa galibin su an haɗa su ne da phyllosilicates masu laushi da kauri (~64–88 vol.%; Hoto na 1a, b, Ƙarin Hoto na 1). da ƙarin tebur na 1). Phyllosilicates masu kauri suna faruwa ne a matsayin tarin pinnate (har zuwa goma na microns a girma) a cikin ƙananan matrices masu kauri, masu wadataccen phyllosilicate (ƙasa da ƙananan microns a girma). Barbashi masu kauri sune symbionts na serpentine-saponite (Hoto na 1c). Taswirar (Si + Al)-Mg-Fe kuma tana nuna cewa babban matrix na silicate mai kauri yana da tsaka-tsaki tsakanin serpentine da saponite (Hoto na 2a, b). Matrix ɗin phyllosilicate ya ƙunshi ma'adanai na carbonate (~2–21 vol.%), ma'adanai na sulfide (~2.4–5.5 vol.%), da magnetite (~3.6–6.8 vol.%). Ɗaya daga cikin ƙwayoyin da aka bincika a cikin wannan binciken (C0009) ya ƙunshi ƙaramin adadin (~0.5 vol.%) na silicates na anhydrous (olivine da pyroxene), wanda zai iya taimakawa wajen gano tushen abin da ya samar da dutsen Ryugu mai ɗanɗano5. Wannan silicate na anhydrous ba shi da yawa a cikin ƙwayoyin Ryugu kuma an gano shi da kyau kawai a cikin ƙwayoyin C0009. Carbonates suna nan a cikin matrix a matsayin gutsuttsura (ƙasa da ƴan microns ɗari), galibi dolomite, tare da ƙananan adadin calcium carbonate da brinell. Magnetite yana faruwa ne azaman ƙwayoyin da aka ware, framboids, plaques, ko tarin ƙwallo. Ana wakiltar sulfides galibi ta hanyar pyrrhotite a cikin nau'i na prisms/faranti ko laths marasa tsari. Matrix ɗin ya ƙunshi babban adadin submicron pentlandite ko kuma a hade shi da pyrrhotite. Matakan da ke ɗauke da sinadarin carbon (<10 µm a girman) suna faruwa ko'ina a cikin matrix mai ɗauke da sinadarin phyllosilicate. Matakan da ke ɗauke da sinadarin carbon (<10 µm a girman) suna faruwa ko'ina a cikin matrix mai ɗauke da sinadarin phyllosilicate. Богатые углеродом фазы (размером <10 мкм) Matakan da ke ɗauke da sinadarin carbon (<10 µm a girman) suna faruwa ko'ina a cikin matrix mai ɗauke da sinadarin phyllosilicate.富含碳的相（尺寸<10 µm）普遍存在于富含层状硅酸盐的基质中。富含碳的相（尺寸<10 µm）普遍存在于富含层状硅酸盐的基质中。 Богатые углеродом фазы (размером <10 мкм) Matakan da ke ɗauke da sinadarin carbon (<10 µm a girma) sun fi yawa a cikin matrix mai ɗauke da sinadarin phyllosilicate.An nuna sauran ma'adanai masu taimako a cikin Jadawali na Ƙarin Bayani na 1. Jerin ma'adanai da aka ƙayyade daga tsarin X-ray diffraction na cakuda C0087 da A0029 da A0037 ya yi daidai da wanda aka ƙayyade a cikin chondrite na CI (Orgueil), amma ya bambanta sosai da CY da CM (nau'in Mighei) chondrites (Hoto na 1 tare da bayanai da aka faɗaɗa da Hoto na Ƙarin Bayani na 2). Jimlar abubuwan da ke cikin hatsin Ryugu (A0098, C0068) shi ma ya yi daidai da chondrite 6 CI (bayanan da aka faɗaɗa, Hoto na 2 da Tebur na Ƙarin Bayani na 2). Sabanin haka, CM chondrites suna raguwa a cikin abubuwa masu matsakaici da masu saurin canzawa, musamman Mn da Zn, kuma mafi girma a cikin abubuwan da ba su da ƙarfin jurewa7. Yawan wasu abubuwa ya bambanta sosai, wanda zai iya zama nuni na bambancin da ke cikin samfurin saboda ƙaramin girman ƙwayoyin cuta da kuma sakamakon bin diddigin samfurin. Duk halayen petrologic, mineralological da elemental sun nuna cewa hatsin Ryugu suna kama da chondrites CI8,9,10. Wani abin da ya bambanta shi ne rashin ferrihydrite da sulfate a cikin hatsin Ryugu, wanda ke nuna cewa waɗannan ma'adanai a cikin CI chondrites an samar da su ne ta hanyar yanayin ƙasa.
a, Hoton X-ray mai hade da Mg Kα (ja), Ca Kα (kore), Fe Kα (shuɗi), da S Kα (rawaya) sashin busasshe mai gogewa C0068. Kashi ya ƙunshi silicates masu layi (ja: ~88 vol%), carbonates (dolomite; kore mai haske: ~1.6 vol%), magnetite (shuɗi: ~5.3 vol%) da sulfides (rawaya: sulfide = ~2.5% vol. essay. b, hoton yankin contour a cikin electrons masu warwatse a baya akan a. Bru - balagagge; Dole - dolomite; FeS shine ƙarfe sulfide; Mag - magnetite; ruwan 'ya'yan itace - sabulun sabulu; Srp - serpentine. c, hoton microscopy na lantarki mai watsawa mai ƙuduri mai ƙuduri (TEM) na haɗin saponite-serpentine na yau da kullun wanda ke nuna madaurin lattice na serpentine da saponite na 0.7 nm da 1.1 nm, bi da bi.
An nuna abun da ke cikin matrix da silicate mai layi (a%) na Ryugu A0037 (da'irori ja masu ƙarfi) da C0068 (da'irori masu shuɗi masu ƙarfi) a cikin tsarin ternary (Si+Al)-Mg-Fe. a, Sakamakon Electron Probe Microanalysis (EPMA) da aka zana akan CI chondrites (Ivuna, Orgueil, Alais)16 da aka nuna a launin toka don kwatantawa. b, An nuna nazarin Scanning TEM (STEM) da kuma nazarin X-ray dispersive energy dispersive (EDS) don kwatantawa da meteorites na Orgueil9 da Murchison46 da hydrated IDP47. An yi nazarin phyllosilicates masu laushi da kauri, suna guje wa ƙananan ƙwayoyin ƙarfe sulfide. Layukan da aka zana a cikin a da b suna nuna layukan narkewar saponite da serpentine. Abun da ke cikin ƙarfe mai yawa a cikin a na iya zama saboda ƙwayoyin sulfide na baƙin ƙarfe na submicron a cikin ƙwayoyin silicate masu layi, waɗanda ba za a iya cire su ta hanyar ƙudurin sarari na nazarin EPMA ba. Ma'aunin bayanai masu yawan Si fiye da saponite a cikin b na iya faruwa ne sakamakon kasancewar kayan da ke da silikon amorphous mai siffar nanos a cikin mahadar layin phyllosilicate. Adadin nazarin: N=69 don A0037, N=68 don EPMA, N=68 don C0068, N=19 don A0037 da N=27 don C0068 don STEM-EDS. c, taswirar isotope na barbashi na trioxy Ryugu C0014-4 idan aka kwatanta da ƙimar chondrite CI (Orgueil), CY (Y-82162) da bayanan adabi (CM da C2-ung)41,48,49. Mun sami bayanai don meteorites na Orgueil da Y-82162. CCAM layi ne na ma'adanai na carbonaceous chondrite, TFL layin raba ƙasa ne. d, Taswirorin Δ17O da δ18O na barbashi na Ryugu C0014-4, CI chondrite (Orgueil), da CY chondrite (Y-82162) (wannan binciken). Δ17O_Ryugu: Darajar Δ17O C0014-1. Δ17O_Orgueil: Matsakaicin ƙimar Δ17O ga Orgueil. Δ17O_Y-82162: Matsakaicin ƙimar Δ17O ga Y-82162. Bayanan CI da CY daga wallafe-wallafen 41, 48, 49 kuma an nuna su don kwatantawa.
An yi nazarin isotope mai yawa na iskar oxygen akan samfurin 1.83 mg na kayan da aka cire daga granular C0014 ta hanyar amfani da hasken laser (Hanyoyi). Don kwatantawa, mun gudanar da kwafi bakwai na Orgueil (CI) (jimillar nauyi = 8.96 mg) da kwafi bakwai na Y-82162 (CY) (jimillar nauyi = 5.11 mg) (Jadawalin Karin Bayani na 3).
A hoto na 2d, an nuna rabuwar Δ17O da δ18O tsakanin matsakaicin nauyin barbashi na Orgueil da Ryugu idan aka kwatanta da Y-82162. Δ17O na barbashi na Ryugu C0014-4 ya fi na barbashi na Orgeil girma, duk da cewa an haɗa shi da sd 2. Barbashi na Ryugu suna da ƙimar Δ17O mafi girma idan aka kwatanta da Orgeil, wanda zai iya nuna gurɓataccen ƙasa na ƙarshen tun faɗuwar sa a 1864. Sauyewar yanayi a cikin yanayin ƙasa11 dole ne ya haifar da haɗakar iskar oxygen ta yanayi, yana kawo cikakken bincike kusa da layin rarrabuwa na ƙasa (TFL). Wannan ƙarshe ya yi daidai da bayanan ma'adinai (wanda aka tattauna a baya) cewa hatsin Ryugu ba su ƙunshi hydrates ko sulfates ba, yayin da Orgeil ke da shi.
Dangane da bayanan ma'adanai da ke sama, waɗannan sakamakon suna goyon bayan alaƙa tsakanin hatsin Ryugu da chondrites na CI, amma sun kawar da alaƙar CY chondrites. Gaskiyar cewa hatsin Ryugu ba su da alaƙa da CY chondrites, waɗanda ke nuna alamun rashin ruwa a jiki, abin mamaki ne. Abubuwan da aka lura a ko'ina game da Ryugu sun nuna cewa ya sha ruwa a jiki kuma saboda haka wataƙila ya ƙunshi kayan CY. Dalilan wannan bambanci a bayyane har yanzu ba a fayyace su ba. An gabatar da nazarin isotope na iskar oxygen na wasu barbashi na Ryugu a cikin takarda ta abokin tarayya 12. Duk da haka, sakamakon wannan saitin bayanai mai tsawo kuma ya yi daidai da alaƙar da ke tsakanin barbashi na Ryugu da chondrites na CI.
Ta amfani da dabarun nazarin ƙananan ƙwayoyin halitta (Ƙarin Hoto na 3), mun bincika rarrabawar sararin samaniya na carbon na halitta a kan dukkan faɗin saman ɓangaren ion mai mayar da hankali (FIB) C0068.25 (Hotuna na 3a–f). Tsarin tsari mai kyau na X-ray sha na carbon (NEXAFS) a gefen kusa a sashe na C0068.25 yana nuna ƙungiyoyi da yawa masu aiki - aromatic ko C=C (285.2 eV), C=O (286.5 eV), CH (287.5 eV) da C(=O)O (288.8 eV) - tsarin graphene ba ya nan a 291.7 eV (Hoto na 3a), wanda ke nufin ƙarancin bambancin zafi. Ƙarfin CH (287.5 eV) na ɓangaren ƙwayoyin halitta na C0068.25 ya bambanta da ƙwayoyin halitta marasa narkewa na chondrites na carbonaceous da aka yi nazari a baya kuma ya fi kama da IDP14 da ƙwayoyin cometary da aka samu ta hanyar aikin Stardust. Kololuwar CH mai ƙarfi a 287.5 eV da kuma kololuwar aromatic ko C=C mai rauni sosai a 285.2 eV sun nuna cewa mahaɗan halitta suna da wadataccen mahaɗan aliphatic (Hoto na 3a da Hoto na Ƙarin 3a). Yankunan da ke da wadataccen mahaɗan aliphatic suna cikin phyllosilicates masu kauri, da kuma a yankunan da ke da ƙarancin tsarin carbon mai ƙamshi (ko C=C) (Hoto na 3c,d). Sabanin haka, A0037,22 (Hoto na Ƙarin 3) ya nuna wani ɓangare na ƙarancin abun ciki na yankuna masu wadataccen carbon aliphatic. Ma'adinan waɗannan hatsi yana da wadataccen carbon, kama da chondrite CI 16, yana nuna babban canjin ruwan tushe (Tebur na Ƙarin 1). Yanayin oxidizing zai fi son yawan ƙwayoyin carbonyl da carboxyl masu aiki a cikin mahaɗan halitta da ke da alaƙa da carbonates. Rarraba submicron na kwayoyin halitta tare da tsarin carbon aliphatic na iya bambanta sosai da rarraba silicates masu kauri. An sami alamun mahaɗan halitta masu alaƙa da phyllosilicate-OH a cikin meteorite na Tagish Lake. Bayanan microanalytical da aka haɗa sun nuna cewa kwayoyin halitta masu wadataccen mahaɗan halitta na iya yaɗuwa a cikin asteroids na nau'in C kuma suna da alaƙa da phyllosilicates. Wannan ƙarshe ya yi daidai da rahotannin da suka gabata na aliphatic/aromatic CHs a cikin barbashi na Ryugu da MicroOmega ya nuna, wani na'urar hangen nesa ta hyperspectral kusa da infrared. Tambaya mai mahimmanci kuma ba a warware ta ba ita ce ko kaddarorin musamman na mahaɗan halitta masu wadataccen carbon da ke da alaƙa da phyllosilicates masu kauri da aka lura a cikin wannan binciken ana samun su ne kawai akan asteroid Ryugu.
a, NEXAFS carbon spectra an daidaita shi zuwa 292 eV a cikin yankin mai ƙanshi (C=C) (ja), a cikin yankin mai arziki aliphatic (kore), da kuma a cikin matrix (shuɗi). Layin launin toka shine Murchison 13 bakan halitta mara narkewa don kwatantawa. au, sashin sulhu. b, Hoton spectral na watsa X-ray na scanning transmission X-ray microscopy (STXM) na carbon K-gefen da ke nuna cewa sashen yana mamaye da carbon. c, RGB composite plot tare da aromatic (C=C) yankuna masu arziki (ja), aliphatic rich zones (kore), da matrix (shuɗi). d, organics masu arziki a cikin aliphatic mahadi suna taruwa a cikin phyllosilicate mai kauri, yankin ya faɗaɗa daga fararen akwatunan dige-dige a cikin b da c. e, manyan nanospheres (ng-1) a cikin yankin da aka faɗaɗa daga farin akwatin dige-dige a cikin b da c. Don: pyrrhotite. Pn: nickel-chromite. f, Nanoscale Secondary Ion Mass Spectrometry (NanoSIMS), Hydrogen (1H), Carbon (12C), da Nitrogen (12C14N) hotunan elemental, hotunan rabon elemental 12C/1H, da hotunan isotope na giciye δD, δ13C, da δ15N - Sashe na PG-1: graphite na presolar tare da ƙarancin wadatar 13C (Tebur na Ƙarin 4).
Nazarin kinetic na lalacewar kwayoyin halitta a cikin meteorites na Murchison na iya samar da muhimman bayanai game da rarrabawar kwayoyin halitta masu aliphatic masu wadataccen hatsi a cikin ƙwayoyin Ryugu. Wannan binciken ya nuna cewa haɗin CH na aliphatic a cikin kwayoyin halitta yana ci gaba har zuwa matsakaicin zafin jiki na kusan 30°C a iyaye da/ko canji tare da alaƙar zafin jiki na lokaci (misali shekaru 200 a 100°C da 0°C shekaru miliyan 100). . Idan ba a dumama abin da ya fara ba a wani zafin jiki da aka bayar fiye da wani lokaci, ana iya kiyaye rarrabawar asali na kwayoyin halitta masu aliphatic masu wadataccen phyllosilicate. Duk da haka, canje-canjen ruwan dutse na tushen dutse na iya rikitar da wannan fassarar, kamar yadda A0037 mai wadataccen carbonate bai nuna wani yanki na aliphatic mai wadataccen carbon da ke da alaƙa da phyllosilicates ba. Wannan canjin yanayin zafi mai ƙarancin yana daidai da kasancewar cubic feldspar a cikin ƙwayoyin Ryugu (Tebur na Ƙarin 1) 20.
Fraction C0068.25 (ng-1; Figures. 3a–c,e) ya ƙunshi babban nanosphere wanda ke nuna ƙamshi mai yawa (ko C=C), matsakaici aliphatic, da rauni na C(=O)O da C=O. . Sa hannun aliphatic carbon bai yi daidai da sa hannun manyan kwayoyin halitta marasa narkewa da nanospheres na halitta da ke da alaƙa da chondrites ba (Hoto na 3a) 17,21. Binciken Raman da infrared spectroscopic na nanospheres a cikin Tafkin Tagish ya nuna cewa sun ƙunshi mahaɗan aliphatic da oxidized da mahaɗan aromatic na polycyclic marasa tsari tare da tsari mai rikitarwa22,23. Saboda matrix da ke kewaye ya ƙunshi kwayoyin halitta masu wadataccen mahaɗan aliphatic, sa hannun aliphatic carbon a cikin ng-1 na iya zama kayan bincike. Abin sha'awa, ng-1 ya ƙunshi silicates amorphous da aka saka (Hoto na 3e), wani yanayi wanda har yanzu ba a bayar da rahotonsa ga duk wani kwayoyin halitta na waje ba. Silicates marasa tsari na iya zama abubuwan halitta na ng-1 ko kuma suna faruwa ne sakamakon rashin daidaituwar silicates masu ruwa/anhydrous ta hanyar ion da/ko electron beam yayin bincike.
Hotunan ion na NanoSIMS na sashin C0068.25 (Hoto na 3f) suna nuna canje-canje iri ɗaya a cikin δ13C da δ15N, ban da hatsin presolar tare da babban wadatar 13C na 30,811‰ (PG-1 a cikin hoton δ13C a cikin Hoto na 3f) (Tebur na Ƙarin 4). Hotunan ƙwayoyin X-ray na farko da hotunan TEM masu ƙuduri mai girma suna nuna yawan carbon kawai da nisan da ke tsakanin jiragen ƙasa na 0.3 nm, wanda ya yi daidai da graphite. Abin lura ne cewa ƙimar δD (841 ± 394‰) da δ15N (169 ± 95‰), waɗanda aka wadatar da su a cikin kwayoyin halitta na aliphatic da ke da alaƙa da phyllosilicates masu kauri, sun zama sun ɗan fi matsakaici ga duk yankin C (δD = 528 ± 139‰). ‰, δ15N = 67 ± 15 ‰) a cikin C0068.25 (Jadawalin Ƙarin 4). Wannan lura ya nuna cewa kwayoyin halitta masu arzikin aliphatic a cikin phyllosilicates masu kauri na iya zama na farko fiye da kwayoyin halitta da ke kewaye, tunda na ƙarshen na iya yin musayar isotopic tare da ruwan da ke kewaye a cikin jikin asali. A madadin haka, waɗannan canje-canjen isotopic suma suna iya alaƙa da tsarin farko na samuwar. Ana fassara cewa silicates masu kauri a cikin CI chondrites an samar da su ne sakamakon ci gaba da sauye-sauye na asali na tarin silicate masu kauri. Abubuwan halitta masu arzikin aliphatic na iya samuwa daga ƙwayoyin da suka riga suka fara aiki a cikin faifai na protoplanetary ko matsakaiciyar interstellar kafin samuwar tsarin hasken rana, sannan aka ɗan canza su kaɗan yayin canjin ruwa na jikin Ryugu (babba). Girman (<1.0 km) na Ryugu ya yi ƙanƙanta sosai don ya iya kula da zafi na ciki yadda zai iya canza ruwa don samar da ma'adanai masu ruwa25. Girman (<1.0 km) na Ryugu ya yi ƙanƙanta sosai don kiyaye isasshen zafi na ciki don canza ruwa don samar da ma'adanai masu ruwa25. Размер (<1,0 км) Рюгу слишком мал, чтобы подерживать достаточное водных минералов25. Girman (<1.0 km) Ryugu ya yi ƙanƙanta sosai don kiyaye isasshen zafi na ciki don canza ruwa don samar da ma'adanai na ruwa25. Ryugu 的尺寸（<1.0 公里）太小，不足以维持内部热量以进行水蚀变形成含水2矉。 Ryugu 的尺寸（<1.0 公里）太小，不足以维持内部热量以进行水蚀变形成含水2矉。 Размер Рюгу (<1,0 км) слишком мал, чтобы подерживать ma'anar 25. Girman Ryugu (<1.0 km) ya yi ƙanƙanta sosai don ya iya ɗaukar zafi na ciki don ya canza ruwa ya samar da ma'adanai na ruwa25.Saboda haka, ana iya buƙatar magabatan Ryugu waɗanda suka kai tsawon kilomita goma a girma. Ma'aunin halitta mai wadataccen mahaɗan aliphatic na iya riƙe rabon isotope na asali saboda alaƙa da phyllosilicates masu kauri. Duk da haka, ainihin yanayin masu ɗaukar nauyi na isotopic bai tabbata ba saboda haɗakar abubuwa daban-daban a cikin waɗannan ɓangarorin FIB. Waɗannan na iya zama abubuwa na halitta masu wadataccen mahaɗan aliphatic a cikin granules na Ryugu ko phyllosilicates masu kauri da ke kewaye da su. Lura cewa ma'aunin halitta a kusan dukkanin chondrites na carbonaceous (gami da CI chondrites) galibi yana da wadata a cikin D fiye da na phyllosilicates, ban da meteorites na CM Paris 24, 26.
Filayen girman δD da δ15N na yanka FIB da aka samu don A0002.23 da A0002.26, A0037.22 da A0037.23 da C0068.23, C0068.25 da C0068.26 yanka FIB (jimillar yanka FIB bakwai daga barbashi uku na Ryugu) An nuna kwatancen NanoSIMS da sauran abubuwa na tsarin hasken rana a cikin hoto na 4 (Tebur na Ƙarin 4)27,28. Canje-canje a cikin girma a cikin δD da δ15N a cikin bayanan A0002, A0037, da C0068 sun yi daidai da waɗanda ke cikin IDP, amma sun fi girma fiye da na CM da CI chondrites (Hoto na 4). Lura cewa kewayon ƙimar δD don samfurin Comet 29 (-240 zuwa 1655‰) ya fi na Ryugu girma. Juzu'in δD da δ15N na bayanan Ryukyu, a matsayin ƙa'ida, sun fi ƙanƙanta fiye da matsakaicin tauraro mai wutsiya na dangin Jupiter da gajimaren Oort (Hoto na 4). Ƙananan ƙimar δD na chondrites na CI na iya nuna tasirin gurɓatar ƙasa a cikin waɗannan samfuran. Ganin kamanceceniya tsakanin Bells, Lake Tagish, da IDP, babban bambancin da ke cikin ƙimar δD da δN a cikin barbashi na Ryugu na iya nuna canje-canje a cikin sa hannun isotopic na farko na abubuwan da suka shafi halitta da ruwa a cikin tsarin hasken rana na farko. Canje-canjen isotopic iri ɗaya a cikin δD da δN a cikin barbashi na Ryugu da IDP suna nuna cewa duka biyun sun iya samuwa daga abu daga tushe ɗaya. Ana tsammanin cewa IDPs sun samo asali ne daga tushen cometary 14. Saboda haka, Ryugu na iya ƙunsar kayan kama da tauraro mai wutsiya da/ko aƙalla tsarin hasken rana na waje. Duk da haka, wannan na iya zama mafi wahala fiye da yadda muka faɗa a nan saboda (1) cakuda ruwan spherulitic da D mai arzikin ruwa akan jikin iyaye 31 da (2) rabon D/H na tauraro a matsayin aikin cometary 32. Duk da haka, ba a fahimci dalilan da suka sa aka lura da bambancin isotopes na hydrogen da nitrogen a cikin barbashi na Ryugu ba, wani ɓangare saboda ƙarancin adadin nazarin da ake da shi a yau. Sakamakon tsarin isotopes na hydrogen da nitrogen har yanzu yana ƙara yiwuwar cewa Ryugu ya ƙunshi mafi yawan kayan daga wajen Tsarin Rana don haka yana iya nuna wasu kamanceceniya da tauraro. Bayanin Ryugu bai nuna wata alaƙa a bayyane tsakanin δ13C da δ15N ba (Tebur na Ƙarin 4).
Tsarin isotopic na gaba ɗaya na barbashi na Ryugu (da'irori ja: A0002, A0037; da'irori shuɗi: C0068) yana da alaƙa da girman hasken rana 27, dangin Jupiter matsakaici (JFC27), da tauraro mai wutsiya na Oort (OCC27), IDP28, da kuma chondrules na carbonaceous. Kwatanta meteorite 27 (CI, CM, CR, C2-ung). An bayar da haɗin isotopic a cikin Tebur na Ƙarin 4. Layukan da aka yi wa alama sune ƙimar isotope na ƙasa don H da N.
Jigilar ƙwayoyin halitta masu canzawa (misali kwayoyin halitta da ruwa) zuwa Duniya ya kasance abin damuwa26,27,33. Submicron kwayoyin halitta da ke da alaƙa da ƙwayoyin halitta masu ƙarfi a cikin ƙwayoyin halitta na Ryugu da aka gano a cikin wannan binciken na iya zama muhimmin tushen ƙwayoyin halitta masu canzawa. Kwayoyin halitta a cikin ƙwayoyin halitta masu ƙarfi suna da kariya daga lalacewa16,34 da lalacewa35 fiye da kwayoyin halitta a cikin ƙananan ƙwayoyin halitta. Mafi girman sinadarin hydrogen a cikin ƙwayoyin halitta yana nufin ba zai yiwu su zama tushen ƙwayoyin halitta masu canzawa da aka kai zuwa Duniya ta farko ba. Ana iya haɗa su da abubuwan da ke ɗauke da sinadarin hydrogen mai sauƙi, kamar yadda aka gabatar kwanan nan a cikin hasashen kasancewar ruwan da iska ke turowa ta hasken rana a cikin silicates.
A cikin wannan binciken, mun nuna cewa meteorites na CI, duk da mahimmancin su na geochemical a matsayin wakilan tsarin hasken rana gabaɗaya, samfuran 6,10 gurɓatattun abubuwa ne na ƙasa. Mun kuma bayar da shaida kai tsaye don hulɗa tsakanin abubuwa masu arziki na aliphatic da ma'adanai masu maƙwabtaka da hydrous kuma muna ba da shawarar cewa Ryugu na iya ƙunsar kayan waje na rana37. Sakamakon wannan binciken ya nuna a sarari mahimmancin ɗaukar samfurin protoasteroids kai tsaye da buƙatar jigilar samfuran da aka dawo da su a ƙarƙashin yanayi mara aiki da tsafta. Shaidar da aka gabatar a nan ta nuna cewa barbashi na Ryugu babu shakka suna ɗaya daga cikin kayan tsarin hasken rana mafi gurɓatawa da ake samu don binciken dakin gwaje-gwaje, kuma ƙarin nazarin waɗannan samfuran masu tamani ba shakka zai faɗaɗa fahimtarmu game da farkon tsarin tsarin hasken rana. Barbashi na Ryugu sune mafi kyawun wakilci na cikakken tsarin tsarin hasken rana.
Domin tantance hadaddun tsarin da halayen sinadarai na samfuran sikelin submicron, mun yi amfani da nazarin synchrotron radiation-based computed tomography (SR-XCT) da SR X-ray diffraction (XRD)-CT, FIB-STXM-NEXAFS-NanoSIMS-TEM. Babu lalacewa, gurɓataccen yanayi saboda yanayin duniya, kuma babu lalacewa daga ƙananan barbashi ko samfuran injiniya. A halin yanzu, mun gudanar da nazarin volumetric mai tsari ta amfani da na'urar daukar hoto ta electron microscopy (SEM)-EDS, EPMA, XRD, instrumental neutron activation analysis (INAA), da kuma na'urar laser oxygen fluorination. An nuna hanyoyin gwajin a cikin Ƙarin Hoto na 3 kuma an bayyana kowane gwaji a cikin sassan masu zuwa.
An samo barbashi daga asteroid Ryugu daga tsarin sake shiga Hayabusa-2 kuma aka kai su Cibiyar Kula da JAXA da ke Sagamihara, Japan, ba tare da gurɓata yanayin Duniya ba4. Bayan bayyanar farko da ba ta lalata ba a wurin da JAXA ke sarrafawa, yi amfani da kwantena masu rufewa tsakanin wurare da jakunkunan kapsul (lu'ulu'u mai siffar saffir mai diamita 10 ko 15 mm da bakin ƙarfe, ya danganta da girman samfurin) don guje wa tsangwama ga muhalli. muhalli. y da/ko gurɓatattun ƙasa (misali tururin ruwa, hydrocarbons, iskar gas ta yanayi da ƙananan barbashi) da gurɓataccen abu tsakanin samfuran yayin shirya samfurin da jigilar su tsakanin cibiyoyi da jami'o'i38. Domin gujewa lalacewa da gurɓatawa sakamakon hulɗa da yanayin duniya (turɓar ruwa da iskar oxygen), duk nau'ikan shirye-shiryen samfura (gami da guntuwar tantalum, ta amfani da matsewar waya mai daidaito (Meiwa Fosis Corporation DWS 3400) da shirye-shiryen yanke epoxy) don shigarwa) an yi su a cikin akwatin safar hannu a ƙarƙashin busasshen N2 mai tsabta (ma'aunin dew: -80 zuwa -60 °C, O2 ~50-100 ppm). Duk abubuwan da aka yi amfani da su a nan ana tsaftace su da haɗin ruwa mai tsarki da ethanol ta amfani da raƙuman ultrasonic na mitoci daban-daban.
A nan mun yi nazarin tarin meteorite na Cibiyar Bincike ta Ƙasa ta Polar Research (NIPR) na Cibiyar Bincike ta Antarctic Meteorite (CI: Orgueil, CM2.4: Yamato (Y)-791198, CY: Y-82162 da CY: Y 980115).
Don canja wurin tsakanin kayan aiki don nazarin SR-XCT, NanoSIMS, STXM-NEXAFS da TEM, mun yi amfani da mai riƙe samfurin duniya mai siriri wanda aka bayyana a cikin binciken da ya gabata38.
An gudanar da nazarin SR-XCT na samfuran Ryugu ta amfani da tsarin CT mai haɗaka na BL20XU/SPring-8. Tsarin CT mai haɗaka ya ƙunshi nau'ikan ma'auni daban-daban: faɗin filin gani da yanayin ƙarancin ƙuduri (WL) don kama dukkan tsarin samfurin, kunkuntar filin gani da yanayin ƙuduri mai girma (NH) don auna daidai girman yankin samfurin. sha'awa da hotunan rediyo don samun tsarin diffraction na girman samfurin, da kuma yin XRD-CT don samun zane na 2D na matakan ma'adinai na kwance a cikin samfurin. Lura cewa duk ma'auni za a iya yi ba tare da amfani da tsarin da aka gina a ciki don cire mai riƙe samfurin daga tushe ba, wanda ke ba da damar ma'aunin CT da XRD-CT daidai. An sanya wa na'urar gano hasken X-ray na yanayin WL (BM AA40P; Hamamatsu Photonics) ƙarin kyamarar 4608 × 4608 pixel metal-oxide-semiconductor (CMOS) (C14120-20P; Hamamatsu Photonics) tare da mai cire haske wanda ya ƙunshi lutetium aluminum garnet guda ɗaya mai kauri µm (Lu3Al5O12:Ce) da ruwan tabarau na relay. Girman pixel a yanayin WL shine kusan 0.848 µm. Don haka, filin gani (FOV) a yanayin WL shine kusan 6 mm a yanayin CT na offset. An sanya na'urar gano hasken X-ray ta yanayin NH (BM AA50; Hamamatsu Photonics) da na'urar gano hasken gadolinium-aluminum-gallium garnet (Gd3Al2Ga3O12) mai kauri µm, kyamarar CMOS (C11440-22CU) mai ƙudurin pixels 2048 × 2048; Hamamatsu Photonics) da kuma na'urar hangen nesa ×20. Girman pixel a yanayin NH shine ~0.25 µm kuma filin gani shine ~0.5 mm. Na'urar gano hasken don yanayin XRD (BM AA60; Hamamatsu Photonics) an sanya mata na'urar gano hasken da ta ƙunshi allon foda na P43 (Gd2O2S:Tb) mai kauri 50 µm, kyamarar CMOS mai ƙudurin pixel 2304 × 2304 (C15440-20UP; Hamamatsu Photonics) da kuma na'urar hangen nesa. Na'urar ganowa tana da girman pixel mai inganci na 19.05 µm da kuma filin kallon 43.9 mm2. Don ƙara FOV, mun yi amfani da tsarin CT mai katsewa a yanayin WL. Hoton haske da aka watsa don sake gina CT ya ƙunshi hoto a cikin kewayon 180° zuwa 360° wanda aka nuna a kwance a kusa da axis na juyawa, da kuma hoto a cikin kewayon 0° zuwa 180°.
A yanayin XRD, ana mayar da hasken X-ray ta hanyar farantin yankin Fresnel. A cikin wannan yanayin, ana sanya na'urar ganowa a 110 mm a bayan samfurin kuma tasha ta 3 mm a gaban na'urar ganowa. An samo hotunan na'urar ganowa a cikin 2θ daga 1.43° zuwa 18.00° (fitilar grating d = 16.6–1.32 Å) tare da tabon X-ray da aka mayar da hankali a ƙasan filin na'urar ganowa. Samfurin yana motsawa a tsaye a tazara ta yau da kullun, tare da rabin juyawa ga kowane matakin na'urar binciken tsaye. Idan barbashin ma'adinai sun cika yanayin Bragg lokacin da aka juya su da 180°, yana yiwuwa a sami bambance-bambancen barbashin ma'adinai a cikin jirgin kwance. Sannan an haɗa hotunan na'urorin ganowa zuwa hoto ɗaya don kowane matakin na'urar binciken tsaye. Yanayin gwajin SR-XRD-CT kusan iri ɗaya ne da na gwajin SR-XRD. A cikin yanayin XRD-CT, na'urar ganowa tana sanya 69 mm a bayan samfurin. Hotunan diffraction a cikin kewayon 2θ suna daga 1.2° zuwa 17.68° (d = 19.73 zuwa 1.35 Å), inda duka hasken X-ray da mai iyakance hasken suna daidai da tsakiyar filin hangen nesa na na'urar ganowa. Duba samfurin a kwance kuma juya samfurin 180°. An sake gina hotunan SR-XRD-CT tare da ƙarfin ma'adinai mafi girma kamar ƙimar pixel. Tare da duba a kwance, yawanci ana duba samfurin a matakai 500-1000.
Ga dukkan gwaje-gwajen, an daidaita ƙarfin X-ray a 30 keV, tunda wannan shine ƙarancin iyakar shigar X-ray cikin meteorites tare da diamita na kusan mm 6. Adadin hotunan da aka samu don duk ma'aunin CT yayin juyawa 180° shine 1800 (3600 don shirin CT na kashewa), kuma lokacin fallasa hotunan shine 100 ms don yanayin WL, 300 ms don yanayin NH, 500 ms don XRD, da 50 ms . ms don XRD-CT ms. Matsakaicin lokacin duba samfurin shine kimanin mintuna 10 a yanayin WL, mintuna 15 a yanayin NH, awanni 3 don XRD, da awanni 8 don SR-XRD-CT.
An sake gina hotunan CT ta hanyar hasashen baya mai juyawa kuma an daidaita su don daidaita ma'aunin rage gudu daga 0 zuwa 80 cm-1. An yi amfani da manhajar Slice don nazarin bayanan 3D kuma an yi amfani da manhajar muXRD don nazarin bayanan XRD.
An goge barbashi na Ryugu da aka gyara daga Epoxy (A0029, A0037, C0009, C0014 da C0068) a hankali a saman har zuwa matakin fim ɗin lu'u-lu'u mai girman 0.5 µm (3M) a ƙarƙashin yanayin bushewa, wanda hakan ya hana kayan ya taɓa saman yayin aikin gogewa. An fara duba saman kowane samfurin ta hanyar amfani da na'urar hangen nesa mai haske sannan aka yi amfani da electrons masu watsawa a baya don samun hotunan mineralogy da texture (BSE) na samfuran da abubuwan NIPR masu inganci ta amfani da JEOL JSM-7100F SEM wanda aka sanye da hoton JEOL JSM-7100F SEM wanda aka sanye da hoton makamashi mai watsawa (AZtec). makamashi. Ga kowane samfurin, an yi nazarin abubuwan da ke cikin manyan abubuwa da ƙananan abubuwa ta amfani da na'urar bincike ta electron (EPMA, JEOL JXA-8200). Yi nazarin barbashi na phyllosilicate da carbonate a 5 nA, ƙa'idodin halitta da na roba a 15 keV, sulfide, magnetite, olivine, da pyroxene a 30 nA. An ƙididdige ma'aunin modal daga taswirar abubuwa da hotunan BSE ta amfani da software na ImageJ 1.53 tare da matakan da suka dace da aka saita ba tare da izini ba ga kowane ma'adinai.
An gudanar da nazarin isotope na iskar oxygen a Jami'ar Open University (Milton Keynes, Birtaniya) ta amfani da tsarin hasken laser na infrared. An kai samfuran Hayabusa2 zuwa Jami'ar Open University 38 a cikin kwantena masu cike da nitrogen don canja wurin tsakanin wurare.
An yi amfani da samfurin a cikin akwatin safar hannu na nitrogen tare da matakin iskar oxygen da aka sa ido a ƙasa da 0.1%. Don aikin nazarin Hayabusa2, an ƙera sabon mai riƙe samfurin Ni, wanda ya ƙunshi ramuka biyu kawai na samfur (diamita 2.5 mm, zurfin 5 mm), ɗaya don ƙwayoyin Hayabusa2 da ɗayan kuma don ma'aunin ciki na obsidian. A lokacin bincike, an rufe rijiyar samfurin da ke ɗauke da kayan Hayabusa2 da taga ta ciki ta BaF2 mai kauri kusan mm 1 da diamita 3 mm don ɗaukar samfurin yayin aikin laser. An kiyaye kwararar BrF5 zuwa samfurin ta hanyar hanyar haɗa iskar gas da aka yanke a cikin mai riƙe samfurin Ni. An kuma sake tsara ɗakin samfurin don a iya cire shi daga layin fluorination na injin sannan a buɗe shi a cikin akwatin safar hannu mai cike da nitrogen. An rufe ɗakin mai sassa biyu da hatimin matsewa na tagulla da manne na sarkar EVAC Quick Release CeFIX 38. Tagar BaF2 mai kauri mm 3 a saman ɗakin tana ba da damar lura da samfurin da dumama laser a lokaci guda. Bayan loda samfurin, sake matse ɗakin kuma sake haɗawa da layin fluorinated. Kafin a yi nazari, an dumama ɗakin samfurin a ƙarƙashin injin tsabtace iska zuwa kimanin digiri 95 na Celsius cikin dare don cire duk wani danshi da ke sha. Bayan an dumama ɗakin cikin dare, an bar shi ya huce zuwa zafin ɗaki sannan aka wanke wurin da ya fallasa ga yanayi yayin canja wurin samfurin da sassa uku na BrF5 don cire danshi. Waɗannan hanyoyin suna tabbatar da cewa samfurin Hayabusa 2 bai fallasa ga yanayi ba kuma bai gurɓata da danshi daga ɓangaren layin fluoride da aka fitar zuwa sararin samaniya ba yayin loda samfurin.
An yi nazarin samfuran barbashi na Ryugu C0014-4 da Orgueil (CI) a cikin yanayin "guda ɗaya" da aka gyara42, yayin da aka yi nazarin Y-82162 (CY) akan tire ɗaya tare da rijiyoyin samfura da yawa41. Saboda abubuwan da ke cikin su ba su da ruwa, ba lallai ba ne a yi amfani da hanya ɗaya don CY chondrites. An yi ɗumama samfuran ta amfani da na'urar daukar hoto ta Photon Machines Inc. infrared CO2 laser. ƙarfin 50 W (10.6 µm) da aka ɗora akan XYZ gantry a gaban BrF5. Tsarin bidiyo da aka gina a ciki yana sa ido kan yadda amsawar take. Bayan an yi fluorine, an goge O2 da aka 'yanta ta amfani da tarkunan nitrogen guda biyu masu cryogenic da kuma gadon KBr mai zafi don cire duk wani sinadarin fluorine da ya wuce kima. An yi nazarin abubuwan da ke cikin iskar oxygen mai tsabta a kan na'urar auna ma'aunin tashoshi biyu ta Thermo Fisher MAT 253 tare da ƙudurin taro na kusan 200.
A wasu lokuta, adadin iskar gas O2 da aka saki yayin amsawar samfurin bai wuce 140 µg ba, wanda shine kimanin iyaka na amfani da na'urar bellows akan ma'aunin MAT 253. A cikin waɗannan yanayi, yi amfani da ƙananan volumes don bincike. Bayan nazarin ƙwayoyin Hayabusa2, an sanya fluorin a cikin ma'aunin obsidian kuma an tantance abun da ke cikin isotope na oxygen ɗinsa.
Ion na ɓangaren NF+ NF3+ yana tsoma baki ga hasken da nauyinsa ya kai 33 (16O17O). Don kawar da wannan matsalar da ke iya tasowa, yawancin samfuran ana sarrafa su ta amfani da hanyoyin rabuwar cryogenic. Ana iya yin hakan a gaba kafin nazarin MAT 253 ko kuma a matsayin bincike na biyu ta hanyar mayar da iskar da aka yi nazari a kanta zuwa gaurayen ƙwayoyin halitta na musamman da kuma sake wucewa bayan rabuwar cryogenic. Rabuwar cryogenic ta ƙunshi samar da iskar gas ga gaurayen ƙwayoyin halitta a zafin nitrogen na ruwa sannan a sake fitar da ita zuwa gaurayen ƙwayoyin halitta na farko a zafin -130°C. Gwaji mai zurfi ya nuna cewa NF+ ya kasance a kan gaurayen ƙwayoyin halitta na farko kuma babu wani babban rarrabuwa da ke faruwa ta amfani da wannan hanyar.
Dangane da maimaita nazarin da aka yi kan ma'aunin obsidian na ciki, daidaiton tsarin gabaɗaya a yanayin bellows shine: ±0.053‰ don δ17O, ±0.095‰ don δ18O, ±0.018‰ don Δ17O (2 sd). An ba da nazarin isotope na iskar oxygen a cikin daidaitaccen bayanin delta, inda aka ƙididdige delta18O kamar haka:
Haka kuma yi amfani da rabon 17O/16O don δ17O. VSMOW shine ma'aunin ƙasa da ƙasa don Ma'aunin Ruwan Teku na Vienna. Δ17O yana wakiltar karkacewa daga layin rarraba ƙasa, kuma dabarar lissafi ita ce: Δ17O = δ17O – 0.52 × δ18O. Duk bayanan da aka gabatar a cikin Tebur na Ƙarin 3 an daidaita su da gibin.
An ciro sassan da suka kai kauri kusan nm 150 zuwa 200 daga barbashin Ryugu ta amfani da kayan aikin Hitachi High Tech SMI4050 FIB a JAMSTEC, Cibiyar Samfur ta Kochi Core. Lura cewa an samo dukkan sassan FIB daga tarkacen barbashi marasa sarrafawa bayan an cire su daga tasoshin da aka cika da iskar gas na N2 don canja wurin abubuwa tsakanin juna. Ba a auna waɗannan gutsuttsuran ta hanyar SR-CT ba, amma an sarrafa su da ƙarancin fallasa ga yanayin ƙasa don guje wa lalacewa da gurɓatawa da ka iya shafar bakan carbon K-gefen. Bayan an ajiye wani Layer mai kariya daga tungsten, an yanke yankin da ake sha'awa (har zuwa 25 × 25 μm2) kuma an narkar da shi da hasken Ga+ ion a ƙarfin lantarki mai sauri na 30 kV, sannan a 5 kV da kuma wutar lantarki ta 40 pA don rage lalacewar saman. Sannan an sanya sassan da suka fi siriri a kan ragar jan ƙarfe mai girma (ragon Kochi) 39 ta amfani da micromanipulator da aka sanye da FIB.
An rufe ƙwayoyin Ryugu A0098 (1.6303mg) da C0068 (0.6483mg) sau biyu a cikin zanen polyethylene mai tsarki mai tsarki a cikin akwatin safar hannu mai cike da nitrogen a kan SPring-8 ba tare da wata hulɗa da yanayin duniya ba. An gudanar da shirye-shiryen samfurin JB-1 (dutsen ma'aunin ƙasa wanda Binciken Ƙasa na Japan ya bayar) a Jami'ar Tokyo Metropolitan.
Ana gudanar da INAA a Cibiyar Nazarin Haɗakar Radiation da Kimiyyar Nukiliya, Jami'ar Kyoto. An yi amfani da samfurin sau biyu tare da zagayawa daban-daban na hasken rana da aka zaɓa bisa ga rabin rayuwar nuclide da aka yi amfani da shi don ƙididdige abubuwa. Da farko, an yi amfani da samfurin a cikin bututun hasken rana na iska na tsawon daƙiƙa 30. Ana amfani da kwararar neutrons masu zafi da sauri a cikin fig. 3 don tantance abubuwan da ke cikin Mg, Al, Ca, Ti, V da Mn. Sinadaran kamar MgO (tsaftacewa 99.99%, Soekawa Chemical), Al (tsaftacewa 99.9%, Soekawa Chemical), da Si metal (tsaftacewa 99.999%, FUJIFILM Wako Pure Chemical) don gyara don hana tasirin nukiliya kamar (n, n). An kuma yi amfani da sodium chloride (tsaftacewa 99.99%; MANAC) don gyara canje-canje a cikin kwararar neutron.
Bayan an yi amfani da hasken neutron, an maye gurbin takardar polyethylene ta waje da sabo, kuma an auna hasken gamma da samfurin da aka fitar nan da nan da na'urar gano Ge. An sake yin amfani da irin waɗannan samfuran na tsawon awanni 4 a cikin bututun hasken iska mai numfashi. 2 yana da kwararar neutron mai zafi da sauri na 5.6 1012 da 1.2 1012 cm-2 s-1, bi da bi, don tantance Na, K, Ca, Sc, Cr, Fe, Co, Ni, Zn, Ga, As, Content Se, Sb, Os, Ir da Au. An yi amfani da samfuran sarrafawa na Ga, As, Se, Sb, Os, Ir, da Au ta hanyar amfani da adadi mai dacewa (daga 10 zuwa 50 μg) na daidaitattun mafita na daidaitattun abubuwan da aka sani a kan takarda guda biyu na tacewa, sannan aka yi amfani da hasken samfuran. An gudanar da ƙidayar hasken gamma a Cibiyar Nazarin Haɗakar Radiation da Kimiyyar Nukiliya, Jami'ar Kyoto da Cibiyar Bincike ta RI, Jami'ar Metropolitan ta Tokyo. Tsarin nazari da kayan bincike don tantance adadi na abubuwan INAA iri ɗaya ne da waɗanda aka bayyana a cikin aikinmu na baya.
An yi amfani da na'urar auna hasken X-ray diffractometer (Rigaku SmartLab) don tattara tsarin diffraction na samfuran Ryugu A0029 (<1 mg), A0037 (≪1 mg) da C0087 (<1 mg) a NIPR. An yi amfani da na'urar auna hasken X-ray diffractometer (Rigaku SmartLab) don tattara tsarin diffraction na samfuran Ryugu A0029 (<1 mg), A0037 (≪1 mg) da C0087 (<1 mg) a NIPR. Рентгеновский дифрактометр (RIGAku SmartLab) C0087 (<1 мг) в NIPR. An yi amfani da na'urar auna hasken X-ray diffractometer (Rigaku SmartLab) don tattara samfuran Ryugu A0029 (<1 mg), A0037 (≪1 mg), da C0087 (<1 mg) a cikin NIPR.使用X 射线衍射仪(Rigaku SmartLab) 在NIPR 收集Ryugu 样品A0029 (<1 mg)、A0037 (<1 mg) 和C0087 (<1 mg) 的衾尡使用X 射线衍射仪(Rigaku SmartLab) 在NIPR 收集Ryugu 样品A0029 (<1 mg)、A0037 (<1 mg) 和C0087 (<1 mg) 的衾尡 Дифрактограммы образцов Ryugu A0029 (<1 мг), A0037 (<1 мг) и C0087 (<1 мг) были получены в NIPR с использовенгование дифрактометра (Rigaku SmartLab). An samo samfuran X-ray na Ryugu A0029 (<1 mg), A0037 (<1 mg) da C0087 (<1 mg) a NIPR ta amfani da na'urar auna hasken X-ray (Rigaku SmartLab).An niƙa dukkan samfuran zuwa foda mai laushi akan wafer silicon mara haske ta amfani da farantin gilashin sapphire sannan a shimfiɗa su daidai akan wafer silicon mara haske ba tare da wani ruwa ba (ruwa ko barasa). Yanayin aunawa sune kamar haka: Ana samar da hasken X-ray na Cu Kα a ƙarfin bututu na 40 kV da kuma kwararar bututu na 40 mA, tsawon yankewa mai iyaka shine 10 mm, kusurwar bambance-bambancen shine (1/6)°, saurin juyawa a cikin jirgin shine 20 rpm, kuma kewayon shine 2θ (kusurwar Bragg biyu) shine 3-100° kuma yana ɗaukar kimanin awanni 28 don yin nazari. An yi amfani da Bragg Brentano optics. Na'urar ganowa mai gano semiconductor silicon mai girma ɗaya (D/teX Ultra 250). An cire X-ray na Cu Kβ ta amfani da matatar Ni. Ta amfani da samfuran da ake da su, an kwatanta ma'aunin saponite na roba na magnesian (JCSS-3501, Kunimine Industries CO. Ltd), serpentine (leaf serpentine, Miyazu, Nikka) da pyrrhotite (monoclinic 4C, Chihua, Mexico Watts) don gano kololuwa da amfani da bayanan diffraction na fayilolin foda daga Cibiyar Duniya don Diffraction Data, dolomite (PDF 01-071-1662) da magnetite (PDF 00-019-0629). An kuma kwatanta bayanan diffraction daga Ryugu da bayanai kan hydroalted carbonaceous chondrites, Orgueil CI, Y-791198 CM2.4, da Y 980115 CY (matakin dumama III, 500–750°C). Kwatancen ya nuna kamanceceniya da Orgueil, amma ba tare da Y-791198 da Y 980115 ba.
An auna siginar NEXAFS mai gefen carbon K na sassan da suka yi kama da na FIB ta amfani da tashar STXM BL4U a cibiyar UVSOR synchrotron a Cibiyar Kimiyyar Molecular (Okazaki, Japan). Girman tabo na wani katako da aka mayar da hankali kan gani tare da farantin yankin Fresnel kusan 50 nm ne. Matakin kuzari shine 0.1 eV don kyakkyawan tsarin yankin gefen kusa (283.6–292.0 eV) da 0.5 eV (280.0–283.5 eV da 292.5–300.0 eV) don yankunan gaba da baya. Lokacin kowane pixel na hoto an saita shi zuwa 2 ms. Bayan fitarwa, an cika ɗakin nazarin STXM da helium a matsin lamba na kusan 20 mbar. Wannan yana taimakawa wajen rage kwararar zafi na kayan aikin X-ray a cikin ɗakin da mai riƙe samfurin, da kuma rage lalacewar samfurin da/ko iskar shaka. An samar da na'urorin carbon na NEXAFS K-edge daga tarin bayanai ta amfani da software na aXis2000 da kuma software na sarrafa bayanai na STXM na musamman. Lura cewa ana amfani da akwatin canja wurin samfurin da akwatin safar hannu don guje wa iskar shaka da gurɓata samfurin.
Bayan nazarin STXM-NEXAFS, an yi nazarin abubuwan da ke cikin isotopic na hydrogen, carbon, da nitrogen na yanka FIB na Ryugu ta amfani da hoton isotope tare da JAMSTEC NanoSIMS 50L. An yi amfani da babban hasken Cs+ mai mayar da hankali na kimanin pA 2 don nazarin isotope na carbon da nitrogen da kuma kusan pA 13 don nazarin isotope na hydrogen a kan yanki na kimanin 24 × 24 µm2 zuwa 30 × 30 µm2 akan samfurin. Bayan feshi na mintuna 3 a kan ƙarfin hasken wutar lantarki na farko, an fara kowane bincike bayan daidaita ƙarfin hasken na biyu. Don nazarin isotope na carbon da nitrogen, an sami hotunan 12C–, 13C–, 16O–, 12C14N– da 12C15N– a lokaci guda ta amfani da gano multiplex na electron multiplier bakwai tare da ƙudurin taro na kusan 9000, wanda ya isa ya raba duk mahaɗan isotope masu dacewa. Tsangwama (watau 12C1H akan 13C da 13C14N akan 12C15N). Don nazarin isotopes na hydrogen, an sami hotunan 1H-, 2D- da 12C- tare da ƙudurin taro na kimanin 3000 tare da gano abubuwa da yawa ta amfani da masu ninka electrons guda uku. Kowane bincike ya ƙunshi hotuna 30 da aka duba na yanki ɗaya, tare da hoto ɗaya wanda ya ƙunshi pixels 256 × 256 don nazarin isotopes na carbon da nitrogen da pixels 128 × 128 don nazarin isotopes na hydrogen. Lokacin jinkiri shine 3000 µs a kowace pixel don nazarin isotopes na carbon da nitrogen da kuma 5000 µs a kowace pixel don nazarin isotopes na hydrogen. Mun yi amfani da 1-hydroxybenzotriazole hydrate azaman matsayin hydrogen, carbon da nitrogen isotopes don daidaita rarrabuwar taro na kayan aiki45.
Domin tantance abun da ke cikin silicon isotopic na presolar graphite a cikin bayanin martaba na FIB C0068-25, mun yi amfani da masu ninka electrons guda shida tare da ƙudurin taro na kusan 9000. Hotunan sun ƙunshi pixels 256 × 256 tare da lokacin jinkiri na 3000 µs a kowace pixel. Mun daidaita kayan aikin rarraba taro ta amfani da wafers na silicon kamar yadda aka tsara hydrogen, carbon, da silicon isotope.
An sarrafa hotunan Isotope ta amfani da manhajar daukar hoto ta NanoSIMS45 ta NASA. An gyara bayanan don lokacin da electron multiplier ya mutu (44 ns) da kuma tasirin isowa a lokaci guda. Daidaitawar duba daban-daban ga kowane hoto don gyara don yawo a hoto yayin saye. Ana ƙirƙirar hoton isotope na ƙarshe ta hanyar ƙara ions na biyu daga kowane hoto don kowane pixel na duba.
Bayan nazarin STXM-NEXAFS da NanoSIMS, an duba sassan FIB iri ɗaya ta amfani da na'urar hangen nesa ta lantarki (JEOL JEM-ARM200F) a ƙarfin lantarki mai sauri na 200 kV a Kochi, JAMSTEC. An lura da tsarin ƙananan ta amfani da na'urar hangen nesa mai haske da kuma na'urar hangen nesa mai kusurwa mai girma TEM a cikin filin duhu. An gano matakan ma'adinai ta hanyar diffraction na electron da hoton lattice band, kuma an gudanar da nazarin sinadarai ta hanyar EDS tare da na'urar gano silicon drift 100 mm2 da kuma software na JEOL Analysis Station 4.30. Don nazarin adadi, an auna ƙarfin X-ray na musamman ga kowane abu a cikin yanayin binciken TEM tare da lokacin tattara bayanai na 30 s, yankin duba haske na ~100 × 100 nm2, da kuma hasken rana na 50 pA. An ƙayyade rabon (Si + Al)-Mg-Fe a cikin silicates masu layi ta amfani da ma'aunin gwaji na k, wanda aka gyara don kauri, wanda aka samo daga ma'aunin pyropagarnet na halitta.
Duk hotuna da nazarin da aka yi amfani da su a wannan binciken suna samuwa a tsarin adana bayanai da sadarwa na JAXA (DARTS) https://www.darts.isas.jaxa.jp/curation/hayabusa2. Wannan labarin ya bayar da bayanan asali.
Kitari, K. da sauransu. Tsarin saman asteroid 162173 Ryugu kamar yadda kayan aikin Hayabusa2 NIRS3 suka lura. Kimiyya 364, 272–275.
Kim, AJ Yamato-type carbonaceous chondrites (CY): analogues na saman Ryugu asteroid? Geochemistry 79, 125531 (2019).
Pilorjet, S. da sauransu. An yi nazarin farko na samfuran Ryugu ta amfani da na'urar hangen nesa ta MicroOmega. National Astron. 6, 221–225 (2021).
Yada, T. da sauransu. Binciken farko na samfurin Hyabusa2 da aka dawo da shi daga asteroid na nau'in C-type Ryugu. National Astron. 6, 214–220 (2021).