# Asalin ruwa a doron ƙasa

| Asalin ruwa a doron ƙasa |
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| research question (en)  da source type (en)  |
| Bayanai |
| Fuskar | water on Earth (en)  |

Ruwa ya mamaye kusan kashi 71% na saman dandalin duniya.
Duniya ita ce ta musamman a tsakanin taurari (planets) da aka sani wajen samun tekuna na ruwa mai gudu a samanta. An dade ana tunanin cewa ruwan duniya bai samo asali ba daga yankin da tauraron ya kafu a cikin faifan protoplanetary disk. Maimakon haka, an yi hasashen cewa dole ne a ce an kawo ruwa da sauran abubuwa masu tashi (volatiles) zuwa duniya daga can nesa na tsarin Solar System daga baya a cikin tarihinta. Sai dai, binciken baya-bayan nan ya nuna cewa hydrogen da ke cikin karkashin kasa ya taka rawa wajen kafuwar tekun. Wadannan ra'ayoyi guda biyu ba sa kore juna, domin akwai kuma shaidu da ke nuna cewa an kawo ruwa duniya ta hanyar faduwar kananan taurari masu kankara (icy planetesimals) wadanda ke da siffa iri daya da asteroid da ke can gefen waje na rukunin asteroid belt.

Ruwa mai gudu, wanda yake da mahimmanci ga dukkan siffofin rayuwa da aka sani, ya ci gaba da kasancewa a saman duniya saboda tauraron yana nesa ta dacewa (wanda aka sani da habitable zone) daga Rana ta yadda ba ya rasa ruwansa, kuma ba ya da nisa sosai da zai sa yanayin sanyi ya sanya dukkan ruwan da ke kan tauraron ya daskare.

## Tarihin ruwa a duniya

Wani abu daya wajen kiyasin lokacin da ruwa ya bayyana a duniya shi ne cewa ana ci gaba da asarar ruwa zuwa sararin samaniya. Kwayoyin H2O a sararin samaniya suna rarrabuwa ta hanyar photolysis, kuma sakamakon haka atoms na hydrogen masu 'yanci a wasu lokutan suna iya tserewa daga karfin maganadisu na duniya (Atmospheric escape). Lokacin da duniya take da kuruciya kuma ba ta da girma sosai, da an fi samun asarar ruwa cikin sauki zuwa sararin samaniya. Abubuwa masu fita da wuri kamar hydrogen da helium ana ranar za su rika yoyo daga sararin samaniya akai-akai, amma adadin isotopic ratios na iskar noble gases masu nauyi a sararin samaniya na zamani sun nuna cewa hatta abubuwa masu nauyi a sararin samaniyar farko sun fuskanci gagarumar asara. Musamman ma, xenon yana da amfani ga lissafin asarar ruwa cikin lokaci. Domin kuwa yana daya daga cikin iskar noble gas (saboda haka ba ya fita daga sararin samaniya ta hanyar sinadarai da sauran abubuwa), sannan kuma kwatanci tsakanin wadatar isotopes dinsa guda tara a sararin samaniya na yau ya bayyana cewa duniya ta yi asarar adadin ruwa kusan daidai da yawan tekun zamani a farkon tarihinta. Kila hakan ya faru ne tsakanin lokutan Hadean da Archean a cikin abubuwan tarihi na barna kamar tasirin da ya kafa wata (moon forming impact).
Duk wani ruwa da ke duniya a lokacin karshen haduwar abubuwa na accretion da ya faru zai iya kasancewa ya tarwatsa ta hanyar tasirin Moon-forming impact (kusan shekaru biliyan 4.5 da suka wuce), wanda kila ya narkar da mafi yawan bawon duniya (crust) da saman bargo (upper mantle) sannan ya haifar da sararin samaniya na hayakin dutse a kewayen matashin tauraron. Hayakin dutsen zai daskare a cikin shekaru dubu biyu, yana barin abubuwa masu zafi wadanda kila suka haifar da mafi yawan carbon dioxide a sararin samaniya tare da hydrogen da tururin ruwa (water vapor). Bayan haka, tekunan ruwa masu gudu suna iya kasancewa sun wanzu duk da yanayin zafi na saman duniya na 230°C saboda karuwar karfin iska na CO2 a sararin samaniya. Yayin da sanyin ya ci gaba, an kwashe mafi yawan CO2 daga sararin samaniya ta hanyar subduction da narkewa a cikin ruwan teku, amma matakan sun rika girgiza sosai yayin da sabbin sassa na saman kasa da bargo (mantle) suka bayyana.

Wannan pillow basalt da ke kasan teku kusa da Hawaii ya kafu ne lokacin da magma ta fito a karkashin ruwa. Wasu tsofaffin siffofin pillow basalt suna ba da shaida kan kasancewar manyan tarin ruwa da can dadewa a tarihin duniya.
Shaidar kasa (geological evidence) ita ma tana taimakawa wajen kayyade lokacin da ruwa mai gudu ya kasance a duniya. Wani samfur na pillow basalt (wani nau'in dutse da ke kafuwa yayin fitowar hayaki a karkashin ruwa) an samo shi daga Isua Greenstone Belt kuma yana ba da shaidar cewa ruwa ya kasance a duniya shekaru biliyan 3.8 da suka wuce. A cikin Nuvvuagittuq Greenstone Belt, Quebec, Canada, duwatsun da wani bincike ya kiyasta shekarunsu a biliyan 3.8 da kuma shekaru biliyan 4.28 ta wani binciken daban sun nuna shaidar kasancewar ruwa a wadannan shekaru. Idan har tekuna sun wanzu kafin wannan lokaci, har yanzu ba a gano wata shaidar kasa ba (wanda kila hakan ya faru ne saboda an lalata irin wadannan shaidu na asali ta hanyar ayyukan kasa kamar crustal recycling). Koma bayan nan, a watan Agusta 2020, masu bincike sun ba da rahoton cewa isasshen ruwa na cika tekuna yana iya kasancewa yana kan duniya tun daga farkon kafuwar tauraron.

Ba kamar duwatsu ba, sinadaran ma'adinai da ake kira zircons suna da matukar juriya ga canjin yanayi da ayyukan kasa don haka ana amfani da su wajen fahimtar yanayi a farkon farkon duniya. Shaidar ma'adinai daga zircons ta nuna cewa ruwa mai gudu da sararin samaniya dole ne su kasance sun kasance shekaru biliyan 4.404 ± 0.008 da suka wuce, jim kadan bayan kafuwar duniya. Wannan yana gabatar da wani abu na rudani, saboda hasashen sanyin farkon duniya (cool early Earth hypothesis) ya nuna yanayin zafi yana da sanyi sosai da zai daskare ruwa tsakanin kimanin shekaru biliyan 4.4 da biliyan 4.0 da suka wuce. Wasu binciken na zircons da aka samo a cikin dutsen Hadean na kasar Australia sun nuna alamun kasancewar plate tectonics tun farkon shekaru biliyan 4 da suka wuce. Idan hakan gaskiya ne, yana nufin cewa maimakon yanayi mai zafi, narkakken yanki da sararin samaniya cike da carbon dioxide, saman farkon duniyar ya kasance da yawa kamar yadda yake a yau (dangane da kariya ta thermal insulation). Ayyukan plate tectonics suna kama dimbin CO2, ta haka suna rage illolin greenhouse effects, wanda ke haifar da raguwar yanayin zafi na saman kasa da kuma kafuwar gaurayawan duwatsu da ruwa mai gudu.

## Kayyadadden Ruwan Duniya

A ina ake samun ruwa a duniya kuma a wane kaso
Yayin da mafi yawan saman duniya ke cike da tekuna, wadancan tekunan suna wakiltar dan kankanin kaso ne na girman tauraron. Girman nauyin tekunan duniya an kiyasta shi da 1.37 × 1021 kg, wanda yake daidai da 0.023% na daukacin girman duniya, 6.0 × 1024 kg. An kiyasta kararin 5.0 × 1020 kg na ruwa yana kasancewa a matsayin kankara, tafkuna, koguna, ruwan karkashin kasa, da tururin ruwa na sararin samaniya. Gagarumin adadin ruwa kuma yana ajiye a cikin bawon duniya (crust), bargo (mantle), da tsakiyar kasa (core). Ba kamar kwayoyin H2O na daban da ake samu a saman kasa ba, ruwa a cikin ciki yana kasancewa ne musamman a cikin ma'adinai masu dauke da ruwa (hydrated minerals) ko a matsayin gurbatattun adadin hydrogen da ke hade da atoms na iskar oxygen a cikin ma'adinai marasa ruwa. Hydrated silicates a saman kasa suna safarar ruwa zuwa cikin bargo a yankunan iyakar plate na convergent plate boundaries, inda ake tura bawon teku zuwa karkashin bawon nahiya (continental crust). Yayin da yake da wuya a kiyasta daukacin abun cikin ruwa na bargo saboda karancin samfura, kimanin ninki uku na nauyin tekunan duniya za a iya adana shi a can. Haka zalika, tsakiyar duniya na iya daukar hydrogen na kimanin tekuna hudu zuwa biyar.

Yayin da ba a dauke shi a matsayin daya daga cikin manyan hanyoyin samar da ruwa a tauraron ba, ya kamata kuma a lura cewa ayyukan halittu kamar photosynthesis da numfashi (respiration) sune muhimman abubuwa a cikin zagayowar ruwa (hydrologic cycling) a duniya. Wadannan ayyuka kila sun kasance da rawa mafi mahimmanci a farkon duniya, kuma kamar haka, suna iya tasiri ga adadin ruwan da ke akwai a wani yanki na musamman a wani lokaci. Wannan ya faru ne saboda daya daga cikin wadannan ayyukan da aka ambata yana cinye ruwa, yayin da guda kuma yake samar da ruwa, kuma daidaito a tsakanyansu shi ne ainihin abin da ke tantance tasirinsu. Idan photosynthesis ya faru a matakin da ya fi na numfashi, kayyadadden ruwan duniya zai ragu, yayin da idan numfashi ya faru a matakin da ya fi na photosynthesis, kayyadadden ruwan duniya zai karu.

## Hasashe kan asalin ruwan Duniya

### Daga cikin Duniya kanta

Miozzi, et al., (2025) sun ba da shawara cewa tekun magma mai dauke da hydrogen zai iya kasancewa a cikin duniyar kanta a yanayin zafi na sama da 4000 K.
Gwaje-gwajen Miozzi, et al., (2025) sun gano cewa dimbin hydrogen na iya narkewa a cikin narkakkiyar magma a 4000 K, tare da karancin dogaro ga matsin lamba, daga 16 zuwa 60 GPa. Bugu da kari, raguwar iron oxide ta hanyar hydrogen tana haifar da samar da adadi mai yawa na ruwa, tare da kafuwar digon karfe (iron blebs).

### Tushe na bayan Duniya

Ruwa yana da mafi ƙarancin yanayin daskarewa/tashi (condensation temperature) idan aka kwatanta shi da sauran abubuwan da ke kafa duniyoyin cikin gida (terrestrial planets) a cikin tsarin Solar System, kamar ƙarfe da silicates. Yankin faifan protoplanetary disk mafi kusa da Rana ya kasance da zafi sosai a farkon tarihin tsarin Solar System, tare da yanayin zafi da ya kama daga 500 zuwa 1500 Kelvin ko 200 zuwa 1200 Celsius, kuma saboda haka, ba zai yiwu ba ace tekunan ruwa sun daskare tare da duniya a lokacin da take kafuwa. A can nesa da matashiyar Rana inda yanayin zafi ya yi ƙasa, ruwa zai iya daskarewa kuma ya kafa ƙananan taurari masu ƙanƙara (icy planetesimals), waɗanda suka taru suka kafa gungun Oort cloud. Iyakokin yankin da ƙanƙara za ta iya kafuwa a farkon tsarin Solar System ana kiranta da layin sanyi (frost line ko snow line), kuma tana can a rukunin asteroid belt na zamani, tsakanin kimanin 2.7 zuwa 3.1 astronomical units (AU) daga Rana. Don haka, ya zama dole cewa abubuwan da suka kafu bayan layin sanyi—kamar taurari masu guda (comets), abubuwan bayan Neptune (trans-Neptunian objects), da kuma manyan duwatsun sararin samaniya masu wadatar ruwa (meteoroids)—su ne suka kawo ruwa duniya. Sai dai, lokacin da aka kawo wannan ruwa har yanzu yana fuskantar tambayoyi.

Wani hasashen yana da'awar cewa duniya ta haɗu ta hanyar girma a hankali (accreted) daga ƙananan taurari masu ƙanƙara kimanin shekaru biliyan 4.5 da suka wuce, lokacin da girmanta yake kashi 60 zuwa 90% na girmanta na yanzu. A cikin wannan yanayi, duniya ta sami damar riƙe ruwa ta wata siffa a duk lokacin haɗuwar abubuwa da kuma manyan lokutan karon taurari. Wannan hasashe yana samun goyon baya daga kamanceceniya na yawa da kuma ma'aunin isotope na ruwa tsakanin tsofaffin duwatsun carbonaceous chondrite meteorites da aka sani da kuma duwatsun da suka fito daga Vesta, waɗanda duka biyun suka samo asali daga rukunin asteroid belt na tsarin Solar System. Haka kuma bincike kan ma'aunin osmium isotope shima yana goyon bayan wannan, wanda ke nuna cewa adadi mai yawa na ruwa yana cikin abubuwan da duniya ta haɗu da su tun da wuri.
Ma'aunai na sinadaran samfuran duniyar wata da ayyukan Apollo 15 da 17 suka tattara sun ƙara ba da goyon baya ga wannan, kuma sun nuna cewa ruwa ya riga ya kasance a duniya kafin ma a kafa duniyar Wata.

Tsarin jiri na Solar System zai iya taimakawa wajen bayyana dalilin da yasa taurari masu iskar gas zasu iya tace ƙananan taurari masu ƙanƙara da ke fitowa daga can nesa kafin su iya isa ga duniyoyin cikin gida (terrestrial planets).
Wata matsala guda da wannan hasashen ita ce cewa ma'aunin noble gas isotope na sararin samaniyar duniya sun bambanta da waɗanda ke cikin bargonta (mantle), wanda ke nuna cewa sun kafu ne daga tushe daban-daban. Don bayyana wannan lura, an gabatar da ka'idar "late veneer" inda aka ce an kawo ruwa daga baya sosai a tarihin duniya, bayan tasirin da ya kafa duniyar Wata. Sai dai, fahimtar yanzu game da kafuwar duniya ta ba da damar ƙasa da 1% na abubuwan duniya su haɗu bayan kafuwar Wata, wanda ke nufin cewa abubuwan da suka haɗu daga baya dole ne su kasance masu wadatar ruwa sosai. Samfura na canje-canjen tsarin Solar System na farko sun nuna cewa asteroids masu ƙanƙara ana iya kawo su cikin tsarin Solar System na ciki (gami da Duniya) a wannan lokacin idan Jupiter ta matso kusa da Rana. Sifofin ci gaban Jupiter cikin sauri, sai dai, ya sa ya zama da wuya ga tsarin solar system na ciki ya karɓi abubuwa daga tsarin solar system na waje, yana taƙaita taruwar ruwa a kan duniyoyin cikin gida. Wannan yana ƙari a kan sauran abubuwa, kamar yanayi na Goldilocks zone, inda ruwa mai gudu, kuma ta hakan rayuwa kamar yadda muka sani, za ta iya wanzu, sabanin daskararriyar ƙanƙara da ke kafa duniyoyin ƙanƙara (snowball planets) ko tururin ruwa mai iskar gas da ke kafa manyan duniyoyin iskar gas (gas giants).

Haka kuma hasashe na uku, wanda ke samun goyon baya daga shaidar molybdenum isotope ratios daga wani bincike na shekarar 2019, ya nuna cewa duniya ta sami mafi yawan ruwanta ne daga wannan gagarumin karo na tsakanin taurari (interplanetary collision) wanda ya haifar da kafuwar duniyar Wata.
Kodayake, kamar yadda aka ambata a sama, mafi yawan wannan ruwa zai kasance a cikin siffar iskar gas har sai lokacin da gagarumin sanyaya na duniya ya faru.

Shaidar daga shekarar 2019 ta nuna cewa tsarin molybdenum isotopic na bargon duniya ya samo asali ne daga tsarin Solar System na waje, wanda kila ya kawo ruwa duniya. Bayanin shi ne cewa Theia, tauraron da aka ce a cikin hasashen giant-impact hypothesis ya yi karo da Duniya shekaru biliyan 4.5 da suka wuce inda ya kafa duniyar Wata, yana iya kasancewa ya samo asali ne daga tsarin Solar System na waje maimakon tsarin Solar System na ciki, yana mai tahowa da ruwa da abubuwan da ke ɗauke da carbon tare da shi.

## Binciken geochemical na ruwa a cikin tsarin Solar System

Duwatsun carbonaceous chondrites kamar Allende Meteorite (a sama) wataƙila su ne suka kawo mafi yawan ruwan Duniya, kamar yadda shaidar kamanceceniyar su ta isotope da ruwan teku ta nuna.
Ma'aunin Isotopic ratios suna samar da "sawun yatsa na sinadarai" (chemical fingerprint) na musamman wanda ake amfani da shi wajen kwatanta ruwan Duniya da sauran rumbun adadin ruwa a fadin tsarin Solar System. Wani ma'aunin isotope guda daya, wato na deuterium zuwa hydrogen (D/H), yana da amfani ƙwarai da gaske wajen neman asalin ruwa a Duniya. Hydrogen shi ne sinadarin da ya fi kowane yawa a sararin samaniya, kuma isotopes ɗinsa mai nauyi wato deuterium wani lokacin yana iya ɗaukar gurbin zarran hydrogen a cikin kwayoyin halitta kamar H2O. An halicci mafi yawan deuterium ne a lokacin Big Bang ko a cikin supernovae, saboda haka rarrabuwarsa da ba daidai ba a cikin gungun protosolar nebula ya kasance "kulle" tun a farkon kafuwar tsarin Solar System. Ta hanyar nazarin mabanbantan ma'aunin isotope na Duniya da na sauran abubuwan ƙanƙara a cikin tsarin Solar System, za a iya gudanar da bincike kan asalin da ruwan Duniya ya fito.

### Duniya

Ma'aunin deuterium zuwa hydrogen na ruwan teku a Duniya an san shi daki-daki da cewa shi ne (1.5576 ± 0.0005) × 10−4. Wannan ƙima tana wakiltar haɗakar dukkan tushen da suka ba da gudummawa ga rumbun ruwan Duniya, kuma ana amfani da ita wajen gano asalin tushen ruwan Duniya. Ma'aunin deuterium zuwa hydrogen ya ƙaru a tsawon rayuwar Duniya tsakanin sau 2 zuwa 9 idan aka kwatanta da ma'aunin lokacin asalin kafuwar Duniya, saboda isotope mai sauƙi ya fi saurin fita zuwa sararin samaniya a cikin tsarin asarar iskar gas (atmospheric loss processes). Hydrogen da ke ƙarƙashin ɓasasshen ɓangaren Duniya (Earth's crust) ana tunanin yana da ma'aunin D/H wanda ya fi wakiltar ainihin ma'aunin D/H na asali lokacin kafuwar Duniya, domin kuwa waɗancan tsari na asarar iskar gas ba su cika shafarsa ba. Binciken hydrogen na ƙarƙashin ƙasa da ke cikin narkakken dutsen lava da ya fito kwanan nan an ƙiyasta ya nuna cewa akwai ma'aunin D/H mafi girma da kashi 218‰ a farkon Duniya idan aka kwatanta da ma'aunin na yanzu. Ba a san wani tsari ba da zai iya rage ma'aunin D/H na Duniya a tsawon lokaci. Wannan asara ta isotope mai sauƙi ita ce bayani ɗaya da ya sa Venus take da ma'aunin D/H mai girma sosai, domin ruwan wannan duniyar ya kafe ya zama tururi a lokacin da matsanancin zafi na runaway greenhouse effect ya faru, kuma daga baya ta rasa mafi yawan hydrogen ɗinta zuwa sararin samaniya.

### Asteroids

Tauraron mai wutsiya Comet Halley kamar yaddda na'urar bincike ta Giotto na Hukumar Sararin Samaniya ta Turai ta ɗauki hotonsa a shekarar 1986. Giotto ta tashi kusa da Comet Halley kuma ta binciko matakan isotopic na ƙanƙara da ke tashi daga saman tauraron ta hanyar amfani da na'urar mass spectrometer.
Binciken geochemical da yawa sun kammala cewa asteroids ne mafi kusantar kasancewa babban tushen ruwan Duniya. Duwatsun Carbonaceous chondrites—waɗanda ke cikin rukunin tsofaffin duwatsun meteorites a cikin tsarin Solar System—suna da matakan isotopic da suka fi kusa da ruwan teku. Rukunonin CI da CM na carbonaceous chondrites musamman suna da matakan isotope na hydrogen da nitrogen da suka dace sosai da ruwan tekun Duniya, wanda ke nuna cewa ruwan da ke cikin waɗannan meteorites zai iya zama tushen tekunan Duniya. Wasu duwatsun meteorites guda biyu masu shekaru biliyan 4.5 da aka gano a Duniya waɗanda ke ɗauke da ruwa mai gudu tare da nau'ikan mahaɗan ƙwayoyin halitta masu ƙarancin deuterium sun ƙara tabbatar da wannan hasashen. Ma'aunin deuterium zuwa hydrogen na Duniya na yanzu shima ya dace da na tsofaffin eucrite chondrites, waɗanda suka samo asali daga asteroid Vesta a cikin rukunin asteroid belt na waje. An yi amfani da cewa CI, CM, da eucrite chondrites suna da adadin ruwa da ma'aunin isotope iri ɗaya da tsofaffin protoplanets masu ƙanƙara daga rukunin asteroid belt na waje waɗanda daga baya suka kawo ruwa Duniya.

Wani ƙarin bincike kan barbashi na asteroids ya goyi bayan ka'idar cewa babban tushen ruwan Duniya ya fito ne daga zarran hydrogen da ke cikin iskar rana (solar wind) waɗanda ke haɗuwa da oxygen a kan asteroids sannan kuma su zo Duniya a cikin ƙurar sararin samaniya. Ta hanyar amfani da atom probe tomography, binciken ya gano kwayoyin halitta na hydroxide da ruwa a saman kwayar fure guda ɗaya daga barbashi da aka dawo da su daga asteroid 25143 Itokawa ta hanyar na'urar binciken sararin samaniya ta Japan mai suna Hayabusa.

### Comets

Taurari masu wutsiya (comets) abubuwa ne masu girman kilomita da aka yi su da ƙura da ƙanƙara waɗanda suka samo asali daga Kuiper belt (20-50 AU) da kuma Oort cloud (>5,000 AU), amma suna da madaidaitan hanyoyin juyawa (elliptical orbits) waɗanda ke kawo su cikin tsarin solar system na ciki. Siffofinsu na ƙanƙara da hanyoyinsu na juyawa da ke kawo su cikin tsarin solar system na ciki ya sa sun zama abin manufa don gudanar da ma'aunai na nesa da kuma na zahiri (in situ) na ma'aunin D/H.

Ba zai yiwu ba ace ruwan Duniya ya samo asali ne kawai daga taurari masu wutsiya, tunda ma'aunai na isotope na deuterium zuwa hydrogen (D/H) a cikin taurari masu wutsiya kamar Halley, Hyakutake, Hale–Bopp, C/2002 T7 (LINEAR), da 8P/Tuttle, sun ba da ƙima kusan ninki biyu na ruwan teku. Wannan kuma yana samun goyon baya daga bincike ta hanyar amfani da kwatancen ma'aunin isotope na duka carbon da nitrogen, waɗanda ke nuna cewa kashin kalilan ne na ruwan da ke Duniya ya fito daga taurari masu wutsiya, wanda ke nuna dogaro mafi girma ga abubuwan asteroids da ke shigowa. Ta hanyar amfani da ma'aunin D/H na taurari masu wutsiya, samfura sun yi hasashen cewa ƙasa da 10% na ruwan Duniya ne aka samo shi daga taurari masu wutsiya.

Wasu taurari masu wutsiya masu ɗan gajeren lokaci (< shekaru 20) da ake kira Jupiter family comets wataƙila sun samo asali ne daga Kuiper belt, amma hanyoyin juyawarsu sun fuskanci tasiri daga ƙarfin maganaɗisu (gravitational interactions) na Jupiter ko Neptune. Tauraron mai wutsiya na 67P/Churyumov–Gerasimenko yana ɗaya daga cikin irin waɗannan taurari da suka kasance abin binciken ma'aunin isotopic ta hanyar na'urar sararin samaniya ta Rosetta, wadda ta gano cewa tauraron yana da ma'aunin D/H ninki uku na ruwan tekun Duniya. Wani tauraron na daban na rukunin Jupiter family comet, wato 103P/Hartley 2, yana da ma'aunin D/H wanda ya dace da ruwan tekun Duniya, amma matakan isotope ɗinsa na nitrogen ba su dace da na Duniya ba.

## Manazarta