jike ƙasa

A cikin Janairu 2020, NASA ta ruwaito cewa kumbon TESS ya gano sararin samaniya na farko da zai iya zama mai girman duniya yana kewaya tauraro kimanin shekaru 100 a nesa.

Duniya bangare ne TOI 700 tsarin (TOI yana nufin TESS Abubuwan sha'awa) ƙaramin tauraro ne, ɗan ƙaramin sanyi, watau dwarf na aji M, a cikin ƙungiyar taurarin Goldfish, yana da kusan kashi 40% na girma da girman Rana da rabin zafin samansa.

Abu mai suna TOI 700 d kuma daya ne daga cikin duniyoyi uku da suke kewaya tsakiyarsa, mafi nisa daga gare shi, suna zagaya hanyar tauraro duk kwanaki 37. Yana da nisa daga TOI 700 don a iya fahimta ta yadda za a iya kiyaye ruwa mai ruwa, wanda ke cikin yankin da ake zaune. Tana karbar kusan kashi 86% na makamashin da Rana ta ke baiwa Duniya.

Koyaya, kwaikwaiyon muhalli da masu binciken suka kirkira ta yin amfani da bayanai daga Tauraron Dan Adam na Transiting Exoplanet Survey (TESS) ya nuna cewa TOI 700 d na iya yin hali daban da Duniya. Domin yana jujjuyawa daidai da tauraronsa (ma’ana daya gefen duniya kullum yana cikin hasken rana, daya kuma yana cikin duhu), yadda gajimare da iska ke kadawa zai iya zama mana dan ban mamaki.

1. Kwatanta Duniya da TOI 700 d, tare da hangen nesa na tsarin duniya na nahiyoyi akan exoplanet

Masana ilmin taurari sun tabbatar da gano su tare da taimakon NASA. Spitzer Space Telescopewanda yanzu ya kammala aikinsa. Da farko dai, an bata sunan Toi 700 a matsayin wanda ya fi zafi, wanda hakan ya sa masana ilmin taurari suka yi imani da cewa dukkan duniyoyin guda uku sun yi kusa da juna don haka suna da zafi sosai don tallafawa rayuwa.

Emily Gilbert, memba na tawagar Jami'ar Chicago, ta ce yayin gabatar da binciken. -

Masu binciken suna fatan a nan gaba, kayan aikin kamar James Webb Space Telescopeda NASA ke shirin sanyawa a sararin samaniya a shekarar 2021, za su iya tantance ko duniyoyin suna da yanayi kuma za su iya yin nazarin abubuwan da ke tattare da su.

Masu binciken sun yi amfani da software na kwamfuta don hasashen yanayi tallan kayan kawa planet TOI 700 d. Tun da har yanzu ba a san ko wane iskar gas zai iya kasancewa a cikin yanayinta ba, an gwada zaɓuɓɓuka daban-daban da yanayin yanayi, gami da zaɓuɓɓuka waɗanda ke ɗaukar yanayin yanayin duniya na zamani (77% nitrogen, 21% oxygen, methane da carbon dioxide). yuwuwar abun da ke tattare da yanayi na duniya shekaru biliyan 2,7 da suka gabata (mafi yawa methane da carbon dioxide) har ma da yanayin Martian (yawan carbon dioxide), wanda mai yiwuwa ya wanzu a can shekaru biliyan 3,5 da suka wuce.

Daga waɗannan nau'ikan, an gano cewa idan yanayin TOI 700 d ya ƙunshi haɗin methane, carbon dioxide, ko tururin ruwa, duniyar zata iya zama wurin zama. Yanzu dole ne ƙungiyar ta tabbatar da waɗannan hasashe ta amfani da na'urar hangen nesa ta Webb da aka ambata.

A sa'i daya kuma, kwaikwaiyon yanayi da hukumar NASA ta gudanar sun nuna cewa, yanayin da duniya ke ciki da kuma karfin iskar gas ba su isa su rike ruwan ruwa a samanta ba. Idan muka sanya adadin iskar gas iri ɗaya akan TOI 700 d kamar yadda yake a duniya, zafin saman saman zai kasance ƙasa da sifili.

Kwaikwayo na duk ƙungiyoyin da suka shiga sun nuna cewa yanayin taurari a kusa da kanana da duhu taurari kamar TOI 700, duk da haka, ya bambanta da abin da muke fuskanta a duniyarmu.

Labari mai kayatarwa

Yawancin abin da muka sani game da exoplanets, ko taurari masu kewaya tsarin hasken rana, sun fito ne daga sararin samaniya. Ya leka sararin samaniya daga 2009 zuwa 2018 kuma ya gano sama da taurari 2600 a wajen tsarin hasken rana.

Daga nan ne NASA ta mika sandar binciken ga na’urar bincike ta TESS(2), wadda aka harba a sararin samaniya a watan Afrilun 2018 a shekarar farko ta fara aiki, da kuma wasu abubuwa dari tara da ba a tabbatar da su ba. Don neman taurarin da ba a san su ba ga masana astronomers, masu lura za su zagaya sararin samaniya, ganin isasshen 200 XNUMX. mafi haske taurari.

2. Transit tauraron dan adam don binciken exoplanet

TESS yana amfani da jerin tsarin kyamara mai faɗin kusurwa. Yana da ikon yin nazarin taro, girma, yawa da kewayen babban rukuni na ƙananan taurari. Tauraron dan adam yana aiki bisa ga hanyar Neman nesa don dips mai haske mai yuwuwar nuni zuwa zirga-zirgar duniya - wucewar abubuwan da ke kewayawa a gaban fuskokin taurarin iyayensu.

'Yan watannin da suka gabata sun kasance jerin abubuwan bincike masu ban sha'awa, wani ɓangare na godiya ga sabon binciken sararin samaniya, wani ɓangare tare da taimakon wasu kayan aikin, gami da na tushen ƙasa. A cikin makonnin da suka gabata kafin ganawarmu da tagwayen Duniya, magana ta fito game da gano wata duniyar da ke kewaya rana biyu, kamar Tatooine daga Star Wars!

TOI duniya 1338 b sami XNUMX haske shekaru nesa, a cikin ƙungiyar taurari na Artist. Girmansa yana tsakanin girman Neptune da Saturn. Abun yana fuskantar husufin juna akai-akai na taurarinsa. Suna jujjuya juna a zagaye na kwanaki goma sha biyar, ɗaya ya ɗan fi Rana mu girma, ɗayan kuma ya fi ƙanƙanta.

A watan Yunin 2019, bayanai sun bayyana cewa an gano taurari masu nau'in terrestrial guda biyu a zahiri a bayan sararin samaniyar mu. An ruwaito wannan a cikin wata kasida da aka buga a mujallar Astronomy and Astrophysics. Dukansu rukunin yanar gizon suna cikin yanki mai kyau inda ruwa zai iya samuwa. Wataƙila suna da saman dutse kuma suna kewaya Rana, wanda aka sani da tauraruwar Tigarden (3), wanda yake kawai shekaru 12,5 haske daga Duniya.

- in ji babban marubucin binciken, Matthias Zechmeister, Abokin Bincike, Cibiyar Nazarin Astrophysics, Jami'ar Göttingen, Jamus. -

3. Tsarin tauraron Teegarden, gani

Bi da bi, abubuwan ban sha'awa da ba a san su ba da TESS ta gano a watan Yulin da ya gabata UCAC taurari 4 191-004642, Shekaru saba'in da uku haske daga Duniya.

Tsarin duniya tare da tauraro mai masaukin baki, yanzu ana yiwa lakabi da TOI 270, ya ƙunshi aƙalla taurari uku. Daya daga cikinsu, TOI 270 p, ɗan girma fiye da Duniya, sauran biyun ƙananan Neptunes ne, na rukunin taurari waɗanda ba su wanzu a cikin tsarin hasken rana. Tauraron yana sanyi kuma baya haske sosai, kusan 40% karami kuma ƙasa da girman Rana. Yanayin zafinta ya kai kashi biyu bisa uku na zafi fiye da na abokinmu na taurari.

Tsarin hasken rana TOI 270 yana cikin ƙungiyar taurarin mawaƙa. Taurari da suka yi ta suna kewayawa kusa da tauraro har tauraruwarsu za ta iya shiga tsarin tauraron dan adam na Jupiter (4).

4. Kwatanta tsarin TOI 270 tare da tsarin Jupiter

Ƙarin bincike na wannan tsarin na iya bayyana ƙarin taurari. Wadanda ke kewayawa nesa da Rana fiye da TOI 270 d na iya zama sanyi isa ya riƙe ruwan ruwa kuma a ƙarshe ya haifar da rayuwa.

TESS ya cancanci a duba

Duk da yawan binciken da aka yi na kananan taurarin sararin samaniya, yawancin taurarin iyayensu suna tsakanin mita 600 zuwa 3 nesa. shekarun haske daga Duniya, yayi nisa kuma yayi duhu don cikakken kallo.

Ba kamar Kepler ba, babban abin da TESS ke mayar da hankali a kai shi ne nemo duniyoyi a kusa da maƙwabtan rana waɗanda suke da haske da za a iya gani a yanzu da kuma daga baya tare da wasu kayan aikin. Daga Afrilu 2018 zuwa yanzu, TESS ta riga ta gano fiye da 1500 taurari taurari. Yawancinsu sun fi girman duniya sau biyu kuma suna ɗaukar ƙasa da kwanaki goma don kewayawa. A sakamakon haka, suna samun zafi fiye da duniyarmu, kuma suna da zafi sosai don ruwa mai ruwa ya wanzu a saman su.

Ruwa ne ruwa da ake bukata domin exoplanet ya zama wurin zama. Yana aiki azaman wurin haifuwar sinadarai waɗanda zasu iya hulɗa da juna.

A bisa ka'ida, an yi imanin cewa nau'ikan rayuwa masu ban sha'awa na iya wanzuwa a cikin yanayi mai tsananin matsi ko yanayin zafi sosai - kamar yadda lamarin yake da extremophiles da aka samu a kusa da magudanar ruwa na ruwa, ko kuma tare da ƙwayoyin cuta da ke ɓoye kusan kilomita ɗaya a ƙarƙashin takardar ƙanƙara ta yammacin Antarctic.

Sai dai gano irin wadannan halittu ya samu ne ta yadda mutane suka iya yin nazari kai tsaye kan matsanancin yanayin da suke ciki. Abin takaici, ba a iya gano su a cikin zurfin sararin samaniya, musamman daga nesa na shekaru masu yawa haske.

Neman rayuwa har ma da wurin zama a wajen tsarin hasken rana namu har yanzu ya dogara kacokan akan kallo mai nisa. Filayen ruwan ruwa da ake iya gani waɗanda ke haifar da yuwuwar yanayi masu kyau don rayuwa na iya yin hulɗa tare da yanayin da ke sama, ƙirƙirar sa hannu na rayuwa mai iya ganowa tare da na'urorin hangen nesa na tushen ƙasa. Waɗannan na iya zama abubuwan haɗin iskar gas da aka sani daga Duniya (oxygen, ozone, methane, carbon dioxide da tururin ruwa) ko kuma abubuwan da ke cikin tsohuwar yanayin duniya, alal misali, shekaru biliyan 2,7 da suka gabata (musamman methane da carbon dioxide, amma ba oxygen ba). ).

A cikin neman wuri "daidai daidai" da duniyar da ke zaune a can

Tun bayan gano 51 Pegasi b a cikin 1995, an gano sama da XNUMX exoplanets. A yau mun san tabbas cewa yawancin taurari a cikin taurarinmu da sararin samaniya suna kewaye da tsarin taurari. Amma ƴan dozin dozin ɗin da aka samu sune yuwuwar zama duniyoyi.

Menene ke sa exoplanet zama mazaunin?

Babban yanayin shine ruwan ruwa da aka ambata a sama. Domin hakan ya yiwu, da farko muna buƙatar wannan tsayayyen saman, watau. dutsen ƙasaamma kuma yanayin, kuma mai yawa isa ya haifar da matsa lamba da kuma tasiri da yawan zafin jiki na ruwa.

Kuna kuma buƙata tauraro damawanda ba ya fitar da radiation da yawa a duniyarmu, wanda ke kawar da yanayi kuma yana lalata kwayoyin halitta. Kowane tauraro, gami da Rana namu, koyaushe yana fitar da manyan allurai na radiation, don haka babu shakka zai yi amfani ga wanzuwar rayuwa don kare kanta daga gare ta. wani maganadisukamar yadda tushen ruwa na duniya ya samar.

Duk da haka, tun da akwai wasu hanyoyin da za a iya kare rayuwa daga radiation, wannan abu ne kawai da ake so, ba yanayin da ya dace ba.

A al'adance, masu ilimin taurari suna sha'awar yankunan rayuwa (ecospheres) a cikin tsarin taurari. Waɗannan yankuna ne da ke kewaye da taurari inda yawan zafin jiki ke hana ruwa tafasa ko daskarewa. Ana yawan magana game da wannan yanki. "Zlatovlaski Zone"saboda “daidai don rayuwa”, wanda ke nufin maƙasudin sanannun tatsuniyar yara (5).

5. Yankin rayuwa a kusa da tauraro

Kuma menene muka sani zuwa yanzu game da exoplanets?

Binciken da aka yi ya nuna cewa bambance-bambancen tsarin duniya yana da girma da yawa. Taurari kawai da muka san wani abu kimanin shekaru talatin da suka gabata suna cikin tsarin hasken rana, don haka muna tunanin cewa kananan abubuwa da daskarewa suna kewaya tauraro, sai kawai daga cikinsu akwai sarari da aka tanada don manyan taurari masu iska.

Ya juya, duk da haka, cewa babu "dokoki" game da wurin da taurari suke. Mun ci karo da ƙattai masu iskar gas waɗanda suka kusan shafa tauraronsu (waɗanda ake kira zafi Jupiters), da kuma ƙaramin tsarin taurari masu ƙanƙanta kamar TRAPPIST-1 (6). Wani lokaci taurari suna motsawa a cikin kewayar sararin samaniya a kusa da taurari na binary, kuma akwai kuma taurari masu "yawo", da alama an fitar da su daga tsarin samari, suna iyo da yardar kaina a cikin faifan interstellar.

6. Ganin taurari na tsarin TRAPPIST-1

Don haka, maimakon kamanceceniya ta kusa, muna ganin babban bambance-bambance. Idan wannan ya faru a matakin tsarin, to me yasa yanayin yanayin exoplanet yayi kama da duk abin da muka sani daga yanayin nan kusa?

Kuma, ci gaba da ƙasa, me yasa nau'ikan rayuwa za su kasance kama da waɗanda aka sani a gare mu?

Super category

Dangane da bayanan da Kepler ya tattara, a cikin 2015 wani masanin kimiyyar NASA ya ƙididdige cewa galaxy ɗinmu da kansa yana da. Biliyoyin taurari masu kama da DuniyaI. Masana ilmin taurari da yawa sun jaddada cewa wannan kiyasin ra'ayin mazan jiya ne. Tabbas, ƙarin bincike ya nuna cewa Milky Way zai iya zama gida 10 biliyan duniya taurari.

Masana kimiyya ba sa so su dogara ga taurarin da Kepler ya samu kawai. Hanyar wucewa da ake amfani da ita a cikin wannan na'urar hangen nesa ta fi dacewa don gano manyan taurari (kamar Jupiter) fiye da taurari masu girman duniya. Wannan yana nufin cewa bayanan Kepler yana yiwuwa yana ɗan ɗanɗano adadin taurari kamar namu.

Shahararren na'urar hangen nesa ya ga ƴan ƙanana suna nutsewa a cikin hasken tauraro sakamakon wata duniyar da ke wucewa a gabanta. Manyan abubuwa a fahimta suna toshe ƙarin haske daga taurarinsu, yana sauƙaƙa gano su. Hanyar Kepler ta mai da hankali kan ƙananan, ba taurari masu haske ba, wanda yawansu ya kai kusan kashi ɗaya bisa uku na yawan Rana.

Na'urar hangen nesa ta Kepler, ko da yake ba ta da kyau sosai wajen gano ƙananan taurari, ya sami adadi mai yawa na abin da ake kira super-Earths. Wannan shi ne sunan exoplanets tare da taro mafi girma fiye da Duniya, amma da yawa kasa da Uranus da Neptune, wanda ya fi 14,5 da 17 nauyi fiye da duniyarmu, bi da bi.

Don haka kalmar “Super-Earth” tana nufin tarin duniya ne kawai, ma’ana baya nufin yanayin saman duniya ko kuma wurin zama. Akwai kuma madadin kalmar "gas dwarfs". A cewar wasu, yana iya zama mafi daidai ga abubuwan da ke cikin ɓangaren sama na ma'auni, ko da yake an fi amfani da wani kalma - wanda aka riga aka ambata "mini-Neptune".

An gano farkon super-Earths Alexander Volshchan i Dalea Fraila kewaye Saukewa: PSR B1257+12 a shekarar 1992. Taurari biyu na waje na tsarin sune poltergeysti fobetor - suna da wani taro kamar sau hudu na duniya, wanda ya yi ƙanƙanta don zama kattai na gas.

An gano farkon super-Earth a kusa da babban tauraro mai jerin gwano ta ƙungiyar da ke jagoranta Kogin Eugenioy a 2005. Yana kewayawa Gliese 876 kuma ya karɓi nadi Gliese 876 da (Tun da farko, an gano kattai biyu masu girman Jupiter a cikin wannan tsarin). Kiyasin girmansa ya ninka girman duniya sau 7,5, kuma lokacin juyin juya hali a kusa da shi gajere ne, kamar kwanaki biyu.

Akwai ma abubuwa masu zafi a cikin ajin super-Earth. Misali, an gano shi a cikin 2004 55 Kankri, wanda yake nesa da shekaru arba'in haske, yana kewaya tauraronsa a cikin mafi kankantar zagayowar kowane sanannen exoplanet - sa'o'i 17 da mintuna 40 kacal. A wasu kalmomi, shekara a 55 Cancri e yana ɗaukar ƙasa da sa'o'i 18. Exoplanet yana kewayawa kusan sau 26 kusa da tauraruwarsa fiye da Mercury.

Kusanci ga tauraro yana nufin cewa saman 55 Cancri e kamar na cikin tanderun fashewa ne tare da zafin jiki na akalla 1760 ° C! Sabbin abubuwan dubawa daga na'urar hangen nesa na Spitzer sun nuna cewa 55 Cancri e yana da girma sau 7,8 kuma radius dan kadan fiye da ninki biyu na Duniya. Sakamakon Spitzer ya nuna cewa kusan kashi ɗaya bisa biyar na girman duniya ya kamata su kasance da abubuwa da mahadi masu haske, gami da ruwa. A wannan zafin jiki, wannan yana nufin cewa waɗannan abubuwa za su kasance cikin yanayin "mafi girman gaske" tsakanin ruwa da gas kuma suna iya barin saman duniya.

Amma Super-Earths ba koyaushe ba ne, a watan Yulin da ya gabata, wata ƙungiyar masana taurari ta duniya da ke amfani da TESS ta gano wani sabon nau'in sararin samaniya a cikin ƙungiyar taurarin Hydra, kimanin shekaru talatin da ɗaya daga duniya. Abu mai alama GJ 357 d (7) ninki biyu diamita da kuma sau shida na duniya. Yana kan gefen waje na wurin zama na tauraron. Masana kimiyya sun yi imanin cewa za a iya samun ruwa a saman wannan super-Earth.

Ta ce Diana Kosakovskda Abokin Bincike a Cibiyar Max Planck don Astronomy a Heidelberg, Jamus.

7. Planet GJ 357 d - gani

Tsarin da ke kewaye da tauraro dwarf, kusan kashi ɗaya bisa uku girman girman Rana namu kuma ya fi 40% sanyi, taurarin ƙasa suna ƙara haɓakawa. GJ 357 b da wani super duniya GJ 357 ku. An buga nazarin tsarin a ranar 31 ga Yuli, 2019 a cikin mujallar Astronomy da Astrophysics.

A watan Satumban da ya gabata, masu bincike sun ba da rahoton cewa wani sabon da aka gano super-Earth, 111 haske-shekaru, shi ne "mafi kyawun ɗan takarar mazaunin da aka sani zuwa yanzu." An gano shi a cikin 2015 ta hanyar hangen nesa na Kepler. K2-18 (8) ya bambanta da duniyarmu ta gida. Yana da nauyinsa fiye da sau takwas, ma'ana ko dai wani ƙaton ƙanƙara ne kamar Neptune ko kuma duniyar dutse mai yawa, yanayi mai arzikin hydrogen.

Kewaye na K2-18b ya ninka tauraronsa sau bakwai fiye da nisan duniya da Rana. Koyaya, tunda abin yana kewaya wani dwarf ja mai duhu, wannan kewayawa yana cikin yanki mai dacewa ga rayuwa. Samfuran farko sun yi hasashen cewa yanayin zafi a kan K2-18b yana kewayo daga -73 zuwa 46°C, kuma idan abu yana da kusan haske iri ɗaya da Duniya, matsakaicin zafinsa yakamata yayi kama da namu.

– in ji wani masanin falaki daga Jami’ar College London yayin wani taron manema labarai. Angelos Tsiaras.

Yana da wuya a zama kamar ƙasa

Alamar duniya (kuma ana kiranta tagwayen duniya ko kuma duniya-kamar duniya) duniya ce ko wata mai yanayin muhalli kwatankwacin wanda ake samu a doron kasa.

Dubban tsarin taurarin da aka gano zuwa yanzu sun sha bamban da tsarin hasken rana, yana mai tabbatar da abin da ake kira. kasa kasa hasasheI. Duk da haka, masana falsafa sun yi nuni da cewa sararin samaniya yana da girma ta yadda a wani wuri dole ne a sami duniyar da ke kusan kama da tamu. Yana yiwuwa a nan gaba mai nisa zai yiwu a yi amfani da fasaha don samun kwatankwacin duniya ta hanyar abin da ake kira. . Gaye yanzu ka'idar multitheory suna kuma ba da shawarar cewa takwarorinsu na duniya na iya wanzuwa a cikin wata sararin samaniya, ko ma zama wata siga ta duniya da kanta a cikin sararin samaniya mai kama da juna.

A watan Nuwamban 2013, masana ilmin taurari sun bayar da rahoton cewa, bisa la’akari da bayanai daga na’urar hangen nesa ta Kepler da wasu ayyuka, za a iya samun duniyoyi masu girman duniya sama da biliyan 40 a yankin da ake zaune na taurari kamar rana da jajayen dwarfs a cikin galaxy na Milky Way.

Ƙididdigar ƙididdiga ta nuna cewa mafi kusa da su za a iya cire su daga gare mu ba fiye da shekaru goma sha biyu masu haske ba. A cikin wannan shekarar, 'yan takara da dama da Kepler ya gano masu diamita kasa da sau 1,5 na radius na Duniya an tabbatar da cewa taurari suna kewayawa a yankin da ake zaune. Duk da haka, sai a shekarar 2015 aka sanar da dan takarar farko na kusa da Duniya - egzoplanetę Kepler-452b.

Yiwuwar gano kwatankwacin duniya ya dogara ne musamman akan halayen da kuke son zama kama da su. Daidaitaccen yanayi amma ba cikakke ba: girman duniya, girman girman sararin samaniya, girman tauraro na iyaye da nau'in (watau analog na hasken rana), nisa na orbital da kwanciyar hankali, karkatawar axial da juyawa, irin wannan labarin kasa, kasancewar teku, yanayi da yanayi, magnetosphere mai karfi. .

Idan rayuwa mai rikitarwa ta wanzu a wurin, dazuzzuka za su iya rufe yawancin sararin duniya. Idan rayuwa mai hankali ta wanzu, wasu yankuna na iya zama birni. Duk da haka, neman ainihin kwatanci da Duniya na iya zama mai ruɗi saboda takamaiman yanayi a duniya da kewaye, alal misali, kasancewar wata yana shafar abubuwa da yawa a duniyarmu.

Laboratory Habitability Planetary a Jami'ar Puerto Rico da ke Arecibo kwanan nan ya tattara jerin 'yan takara na analogues na Duniya (9). Mafi sau da yawa, irin wannan nau'in rarrabuwa yana farawa da girma da yawa, amma wannan ma'auni ne na yaudara, wanda aka ba shi, misali, Venus, wanda ke kusa da mu, wanda kusan girmansa daidai da duniya, da kuma irin yanayin da ke cikinta. , An sani.

9. Alkawari exoplanets - m analogues na Duniya, bisa ga Planetary Habitability Laboratory.

Wani ma'auni akai-akai shine cewa analogin Duniya dole ne ya kasance yana da irin wannan ilimin yanayin ƙasa. Misalai da aka fi sani da su sune Mars da Titan, kuma yayin da akwai kamanceceniya ta fuskar yanayi da abubuwan da ke tattare da yadudduka na saman, akwai kuma bambance-bambance masu mahimmanci, kamar zazzabi.

Lalle ne, da yawa surface kayan da landforms tasowa ne kawai a sakamakon hulda da ruwa (misali, yumbu da sedimentary duwatsu) ko a matsayin ta hanyar rayuwa (misali, farar ƙasa ko kwal), hulda da yanayi, volcanic ayyuka. ko shiga tsakani na mutum.

Don haka, dole ne a ƙirƙira ainihin kwatankwacin duniya ta hanyoyi iri ɗaya, da samun yanayi, dutsen mai aman wuta yana mu'amala da sama, ruwa mai ruwa, da wani nau'in rayuwa.

A cikin yanayin yanayi, ana kuma ɗaukar tasirin greenhouse. A ƙarshe, ana amfani da yanayin zafin jiki. Yanayi ne ya rinjayi shi, wanda shi kuma ya rinjayi tasirin duniya da jujjuyawar duniya, kowannen su yana gabatar da sabbin abubuwa.

Wani ma'auni na ingantacciyar kwatance na duniya mai ba da rai shine dole kewayawa kewaye da hasken rana analog. Duk da haka, wannan kashi ba zai iya zama cikakkiyar barata ba, tun da yanayi mai kyau yana iya samar da bayyanar gida na nau'ikan taurari daban-daban.

Misali, a cikin Milky Way, yawancin taurari sun fi Rana ƙanana da duhu. An ambaci ɗaya daga cikinsu a baya MAFARKI-1, yana a nesa na shekaru 10 haske a cikin ƙungiyar taurari na Aquarius kuma yana da kusan sau 2 karami kuma yana da sau 1. ƙasa da haske fiye da Rana, amma akwai akalla taurari shida na duniya a cikin yankin da za a iya rayuwa. Wadannan yanayi na iya zama kamar ba su da kyau ga rayuwa kamar yadda muka san shi, amma TRAPPIST-XNUMX mai yiwuwa yana da tsawon rai a gabanmu fiye da tauraron mu, don haka rayuwa har yanzu tana da lokaci mai yawa don bunkasa a can.

Ruwa yana rufe kashi 70% na saman duniya kuma ana ɗaukarsa ɗaya daga cikin yanayin ƙarfe don wanzuwar sifofin rayuwa da muka sani. Mafi mahimmanci, duniyar ruwa ta duniya ce Kepler-22b, wanda yake a yankin da ake iya rayuwa na tauraro mai kama da rana amma ya fi Duniya girma, ainihin sinadaran da ke tattare da shi har yanzu ba a san shi ba.

An gudanar da shi a cikin 2008 ta hanyar masanin sararin samaniya Michaela Meyerkuma daga Jami'ar Arizona, nazarin ƙurar sararin samaniya a kusa da sababbin taurari kamar Rana ya nuna cewa tsakanin 20 zuwa 60% na analogs na Rana muna da shaidar samuwar taurari masu ban mamaki a cikin matakai masu kama da wadanda suka haifar da samuwar Duniya.

A cikin 2009 Alan Boss daga Cibiyar Kimiyya ta Carnegie ta nuna cewa a cikin galaxy ɗinmu kawai Milky Way zai iya zama Biliyan 100 masu kama da duniyah.

A cikin 2011, NASA's Jet Propulsion Laboratory (JPL), wanda kuma ya dogara da abubuwan lura daga aikin Kepler, ya ƙaddamar da cewa kusan 1,4 zuwa 2,7% na duk taurari masu kama da rana yakamata su kewaya taurari masu girman duniya a cikin wuraren zama. Wannan yana nufin cewa za a iya samun taurari biliyan 2 a cikin Milky Way kadai, kuma idan aka yi la'akari da wannan kiyasin gaskiya ne ga dukan taurari, za a iya ma samun taurari biliyan 50 a sararin samaniya da ake iya gani. 100 quintillion.

A cikin 2013, Cibiyar Harvard-Smithsonian don Astrophysics, ta yin amfani da ƙididdigar ƙididdiga na ƙarin bayanan Kepler, ya nuna cewa akwai aƙalla. Duniya biliyan 17 girman Duniya - ba tare da la'akari da matsayinsu a wuraren zama ba. Wani bincike da aka gudanar a shekarar 2019 ya nuna cewa taurari masu girman duniya suna iya kewaya daya daga cikin taurari shida masu kama da rana.

Tsarin akan kamanni

Fihirisar kamanceceniya ta Duniya (ESI) ma'auni ne da aka ba da shawarar na kamancen wani abu na duniya ko tauraron dan adam na halitta da Duniya. An ƙera shi akan ma'auni daga sifili zuwa ɗaya, tare da sanya duniya ƙimar ɗaya. An yi nufin siga don sauƙaƙe kwatancen taurari a cikin manyan bayanan bayanai.

ESI, wanda aka gabatar a cikin 2011 a cikin mujallar Astrobiology, ya haɗu da bayanai game da radius na duniya, yawa, gudu, da zafin jiki.

Yanar Gizon da ɗaya daga cikin marubutan labarin na 2011 ya kiyaye, Abla Mendes daga Jami'ar Puerto Rico, ya ba da lissafin lissafin ƙididdiga don tsarin tsarin exoplanetary daban-daban. Ana ƙididdige ESI Mendesa ta amfani da dabarar da aka nuna a ciki misali 10ku x_i su_i0 su ne kaddarorin jikin waje dangane da Duniya, v_i ma'auni mai nauyi na kowace dukiya da jimillar adadin kaddarorin. An gina shi akan tushe Bray-Curtis kamanni index.

Nauyin da aka ba kowace dukiya, w_i, shine duk wani zaɓi wanda za'a iya zaɓa don haskaka wasu siffofi akan wasu, ko don cimma maƙasudin da ake so ko matsayi. Gidan yanar gizon ya kuma rarraba abin da ya bayyana a matsayin yiwuwar rayuwa a kan exoplanets da exo-moon bisa ga ma'auni uku: wuri, ESI, da kuma shawarar yiwuwar ajiye kwayoyin halitta a cikin jerin abinci.

A sakamakon haka, an nuna, alal misali, cewa ESI na biyu mafi girma a cikin tsarin hasken rana na Mars ne kuma shine 0,70. Wasu daga cikin exoplanets da aka jera a cikin wannan labarin sun zarce wannan adadi, wasu kuma an gano su kwanan nan Tigarden b yana da mafi girman ESI na kowane tabbataccen exoplanet, a 0,95.

Lokacin da muke magana game da ƙawancen halittu masu kama da duniya, ba dole ba ne mu manta da yuwuwar abubuwan da za a iya rayuwa ko kuma tauraron dan adam exoplanets.

Har yanzu ba a tabbatar da wanzuwar kowane tauraron dan adam na waje ba, amma a cikin Oktoba 2018 Prof. David Kipping ya sanar da gano wani yuwuwar exomoon da ke kewaya abin Kepler-1625b.

Manyan taurari a tsarin hasken rana, irin su Jupiter da Saturn, suna da manyan watanni da za su iya yin aiki ta wasu fannoni. Saboda haka, wasu masana kimiyya sun ba da shawarar cewa manyan taurarin sararin samaniya (da kuma taurari na biyu) na iya samun irin wannan manyan tauraron dan adam masu yuwuwar zama. Wata mai isasshiyar girma yana iya tallafawa yanayi mai kama da Titan da kuma ruwa mai ruwa a saman.

Musamman sha'awa game da wannan shine manyan taurarin sararin samaniya da aka sani suna cikin yankin da ake zaune (kamar Gliese 876 b, 55 Cancer f, Upsilon Andromedae d, 47 Ursa Major b, HD 28185 b, da HD 37124 c) saboda suna iya samun tauraron dan adam na halitta tare da ruwa mai ruwa a saman.

Rayuwa a kusa da tauraro ja ko fari?

Masu dauke da makamai kusan shekaru ashirin na binciken da aka yi a duniyar exoplanets, tuni masana ilmin taurari suka fara samar da hoton yadda duniyar da za ta iya zama, duk da cewa mafi yawan sun mayar da hankali kan abin da muka riga muka sani: wata duniya mai kama da duniya tana kewaya wani dwarf rawaya kamar. namu. Rana, wanda aka keɓe azaman tauraro mai nau'in G. Kuma menene game da ƙaramin tauraron M-taurari, waɗanda akwai ƙari da yawa a cikin Galaxy ɗinmu?

Yaya gidanmu zai kasance idan yana kewaye da dodanniya ja? Amsar kamar Duniya ce, kuma ba kamar Duniya ba.

Daga saman irin wannan tunanin duniyar, da farko za mu ga wata babbar rana. Zai zama kamar sau ɗaya da rabi zuwa sau uku fiye da abin da muke da shi a gaban idanunmu, idan aka yi la'akari da kusancin sararin samaniya. Kamar yadda sunan ke nunawa, rana za ta yi ja saboda yanayin sanyi.

Dwarfs ja suna da dumi sau biyu kamar Rana tamu. Da farko, irin wannan duniyar na iya zama kamar ɗan baƙo ga Duniya, amma ba abin mamaki ba. Haƙiƙanin bambance-bambancen yana bayyana ne kawai idan muka fahimci cewa mafi yawan waɗannan abubuwan suna jujjuya su daidai da tauraro, don haka gefe ɗaya koyaushe yana fuskantar tauraronsa, kamar yadda Watan mu ke yi ga Duniya.

Wannan yana nufin cewa daya bangaren ya kasance cikin duhu sosai, saboda ba shi da hanyar samun haske - sabanin wata, wanda Rana ta dan haska shi daga wancan bangaren. A haƙiƙa, babban zato shine ɓangaren duniyar da ya saura a cikin hasken rana na har abada zai ƙone, kuma abin da ya faɗa cikin dare na har abada zai daskare. Duk da haka... bai kamata ya kasance haka ba.

Shekaru da dama, masana ilmin taurari sun kawar da yankin jajayen dwarf a matsayin filin farautar Duniya, suna ganin cewa raba duniya zuwa sassa biyu mabanbanta ba zai sa ko wannensu ya zama ba za a iya rayuwa ba. Duk da haka, wasu sun lura cewa duniyar sararin samaniya za ta sami takamaiman yanayi wanda zai sa gajimare mai kauri ya taru a gefen rana don hana zafin radiation daga kona saman. Har ila yau, igiyoyin kewayawa za su rarraba zafi a ko'ina cikin duniya.

Bugu da kari, wannan kauri na yanayi zai iya ba da muhimmiyar kariya ta rana daga sauran hadurran radiyo. Jajayen dwarfs matasa suna aiki sosai a cikin shekaru biliyan na farko na ayyukansu, suna fitar da walƙiya da hasken ultraviolet.

Yiwuwar gajimare mai kauri ya kare rayuwa mai yuwuwa, ko da yake halittun hasashe sun fi iya ɓoye zurfi a cikin ruwayen duniyar. A gaskiya ma, masana kimiyya a yau sun gaskata cewa radiation, alal misali, a cikin kewayon ultraviolet, ba ya hana ci gaban kwayoyin halitta. Bayan haka, farkon rayuwa a duniya, wanda dukkanin kwayoyin halitta da aka sani da mu, ciki har da homo sapiens, sun samo asali ne a karkashin yanayi mai karfi UV radiation.

Wannan yayi dai-dai da yanayin da aka yarda dashi akan mafi kusa da duniya kamar exoplanet da aka sani da mu. Masana ilmin taurari daga Jami'ar Cornell sun ce rayuwa a duniya ta fuskanci radiation mai ƙarfi fiye da yadda aka sani daga gare ta Proxima-b.

Proxima-b, wanda yake kawai shekaru 4,24 haske daga tsarin hasken rana da kuma mafi kusa da duniya-kamar dutsen duniya da muka sani (ko da yake ba mu san komai game da shi ba), yana karɓar hasken X-ray sau 250 fiye da Duniya. Hakanan yana iya fuskantar matakan mutuwa na ultraviolet radiation a samanta.

Ana tsammanin yanayin Proxima-b-kamar suna wanzu don TRAPPIST-1, Ross-128b (kusan shekaru goma sha ɗaya haske daga Duniya a cikin ƙungiyar taurari ta Virgo) da LHS-1140 b (shekaru arba'in haske daga Duniya a cikin ƙungiyar taurari Cetus). tsarin.

Wasu zato sun damu fitowar m kwayoyin halitta. Tunda dwarf ja mai duhu ba zai fitar da haske da yawa ba, ana hasashen cewa idan duniyar da ke kewaye da ita ta ƙunshi kwayoyin halitta masu kama da tsire-tsire namu, to dole ne su sami haske a kan nau'ikan tsayin daka mai yawa don photosynthesis, wanda ke nufin cewa "exoplanets" zai iya. kusan baki a ra'ayinmu (duba kuma: ). Duk da haka, yana da kyau a gane a nan cewa tsire-tsire masu launin wanin kore kuma ana san su a duniya, suna ɗaukar haske daban-daban.

Kwanan nan, masu bincike sun yi sha'awar wani nau'i na abubuwa - fararen dwarfs, kama da girman duniya, wanda ba taurari ba ne kawai, amma suna haifar da yanayin da ya dace a kusa da su, yana haskaka makamashi na biliyoyin shekaru, wanda ya sa su zama masu ban sha'awa ga hari. Exoplanetary bincike. .

Ƙananan girmansu kuma, sakamakon haka, babban siginar wucewa na yuwuwar exoplanet yana ba da damar ganin yuwuwar yuwuwar yanayin dusar ƙanƙara, idan akwai, tare da sabbin na'urorin hangen nesa. Masana ilmin taurari suna son yin amfani da duk abubuwan da aka gina da kuma shirye-shiryen kallo, gami da na'urar hangen nesa na James Webb, terrestrial. Babban na'urar hangen nesahaka nan gaba asali, HabEx i LUVUARidan sun tashi.

Akwai matsala guda ɗaya a cikin wannan fage mai ban al'ajabi na faɗaɗa bincike, bincike da bincike, maras muhimmanci a halin yanzu, amma wacce za ta iya ɗaukar lokaci. To, idan, godiya ga ƙarin kayan aikin ci gaba, a ƙarshe mun sami nasarar gano wani exoplanet - tagwayen Duniya wanda ya cika dukkan buƙatun hadaddun, cike da ruwa, iska da zafin jiki daidai, kuma wannan duniyar za ta yi kama da “kyauta” , to, ba tare da fasahar da ke ba da damar tashi a can a wani lokaci mai dacewa ba, sanin cewa yana iya zama azaba.

Amma, an yi sa'a, ba mu sami irin wannan matsalar ba tukuna.