Iyini i-Astrobiology kanye nokufaneleka kwayo
I-Astrobiology isifundo sesayensi sokuphila endaweni yonke: imvelaphi yayo, ukuziphendukela kwemvelo, ukusatshalaliswa, kanye nokwenzeka kokuba khona kwayo ngale koMhlaba. Ngenkathi i-biology ivame ukugxila ezintweni eziphilayo emhlabeni wethu, i-astrobiology yandisa lo mbuzo uye kowodwa omkhulu: ingabe ukuphila kukhona eMhlabeni kuphela, noma ingabe indawo yonke igcwele nezinye izinhlobo zokuphila? Ukuze siphendule lokhu, i-astrobiology ihlanganisa imikhakha eminingi—kusukela ku-biology, i-chemistry, i-physics, i-geology, i-astronomy, kuya kwisayensi yamaplanethi—ngoba “ukuphila” akuyona nje indaba yezinto eziphilayo, kodwa futhi nendawo ezungezile, amandla, amanzi, izakhi zamakhemikhali, nesikhathi.
Yini efundwa yi-astrobiology?
Ngokuvamile, kunemibuzo emithathu emikhulu eyisisekelo se-astrobiology.
Okokuqala, impilo yaqala kanjani? Abacwaningi bazama ukuqonda izinqubo zamakhemikhali angaphambi kwe-biotic ezazingakhiqiza ama-molecule ayinkimbinkimbi njengama-amino acid, ushukela, ama-nucleotide, kanye nezakhiwo ezikwazi ukuphindaphinda. Ukuhlolwa kwelabhorethri, izifundo ze-meteorite, kanye nokulingisa amakhemikhali komkhathi wokuqala woMhlaba konke kuyizindlela zokulandelela "iresiphi" yokuqala kwempilo.
Okwesibili, ukuphila kusinda kanjani futhi kuchume kanjani? Lokhu kuhlanganisa ucwaningo ngemingcele yokuphila. Ama-microorganisms e-Extremophile eMhlabeni—lawo achuma ezindaweni ezishisa kakhulu, ezinosawoti omningi, ezine-asidi omningi, ezibandayo kakhulu, noma ezingakhanyi kakhulu—anikeza izifanekiso ezibalulekile zokucabanga ngokuphila kwamanye amaplanethi noma izinyanga. Lokhu kuphakamisa omunye umbuzo: ingabe ukuphila kuhlale kudinga izimo ezifana nalezo eziseMhlabeni wanamuhla, noma ingabe “izimo ezincane” ezithile zanele?
Okwesithathu, impilo ingaba khona kuphi ngale koMhlaba? I-Astrobiology idweba izindawo ezingaba khona ngaphakathi kwesimiso selanga kanye nama-exoplanets (amaplanethi angaphandle kwesimiso selanga) angase asekele ukuphila, kokubili manje nasesikhathini esidlule. Lokhu kusesha akugxili nje kuphela ezintweni eziphilayo ezihlakaniphile kodwa nasezinhlotsheni zokuphila ezilula njengezinto ezincane—ngoba, ngokwesayensi, izinto ezincane cishe zilula futhi kulula ukuzithola “njengesinyathelo sokuqala.”
Kungani amanzi evame ukukhulunywa ngawo?
Ezingxoxweni eziningi nge-astrobiology, amanzi acwebezelayo avame ukuba yigama elibalulekile. Hhayi ngoba yiwona kuphela umxube ongaba khona, kodwa ngoba konke ukuphila njengoba sazi kuncike kuwo njengendlela yokusabela kwamakhemikhali. Amanzi anezakhiwo ezihlukile: angancibilikisa izinto eziningi, azinzise amazinga okushisa, futhi asekele ukwakheka kwezakhiwo zezinto eziphilayo.
Ngakho-ke, imisebenzi eminingi yasemkhathini iklanywe ngokwesimiso "sokulandela amanzi". Isibonelo, iMars icwaningwa ukuze kufunyanwe ubufakazi bokuthi yake yaba nemifula, amachibi, futhi mhlawumbe ngisho nolwandle. Ngaphezu kwalokho, kunezinyanga eziningana ezibandayo, njenge-Europa (iJupiter ezungezayo) kanye ne-Enceladus (iSaturn ezungezayo), okukholelwa ukuthi zinezilwandle ezingaphansi komhlaba ezifudunyezwa ukushisa kwamaza. Uma kukhona amanzi ahlanzekile, umthombo wamandla, kanye nezakhi zamakhemikhali ezidingekayo, khona-ke kungenzeka ukuthi izinqubo zezinto eziphilayo ziba nokwenzeka kakhulu.
I-Astrobiology ohlelweni lwelanga: kusukela ku-Mars kuya ezinyangeni ezibandayo
I-Mars ibilokhu iyisisulu esiyinhloko ngenxa yokusondela kwayo kanye nemikhondo ye-geological ekhombisa isikhathi esidlule esimanzi. Izindiza ezifana ne-Curiosity kanye ne-Perseverance ziye zafunda amatshe angaphansi komhlaba, amaminerali, kanye namakhemikhali e-organic. Ukugxila kwazo kusekufuneni izimpawu zokuhlala kanye nezimpawu zezinto eziphilayo ezingaba khona, njengephethini yamakhemikhali okunzima ukuwachaza ngezinqubo ezingezona ezezinto eziphilayo zodwa.
I-Europa ne-Enceladus zinikeza izinto ezikhangayo ezahlukene. I-Enceladus inezinqwaba zezinto ezivela ngaphansi komhlaba ezingahlaziywa eduze. Lezi zifana “namasampula amahhala” olwandle olufihliwe, okunikeza ithuba lokubona amakhemikhali ezinto eziphilayo, usawoti, kanye nokungalingani kwamakhemikhali okungenzeka—izinkomba zemithombo yamandla amagciwane angayisebenzisa.
I-Titan, inyanga enkulu kunazo zonke eSaturn, inamachibi e-hydrocarbon (i-methane/ethane) kanye ne-chemistry eyinkimbinkimbi yomkhathi. Nakuba ibanda kakhulu ukuba amanzi ageleze phezu kwamanzi, i-Titan isebenza njengelabhorethri yemvelo yokufunda i-pre-biotic chemistry. Isiza ososayensi ukuqonda izindlela zamakhemikhali ezingaba nomthelela ekuveleni kokuphila, yize izinhlobo zokuphila—uma zikhona—zingase zihluke kakhulu kulezo eziseMhlabeni.
Amaplanethi angaphandle kanye "nendawo okuhlalwa kuyo"
Ngale kwesimiso selanga, i-astrobiology ithuthuka ngokushesha ngenxa yokutholakala kwezinkulungwane zamaplanethi angaphandle. Umqondo owodwa odumile yindawo okuhlalwa kuyo, ibanga ukusuka enkanyezini lapho amanzi acwebezelayo angahlala khona endaweni yeplanethi (uma kucatshangelwa ukuthi kunomoya owanele). Kodwa-ke, lo mqondo umane nje uyisiqalo. Ukuhlala kuyo kuncike ezintweni eziningi: ukwakheka komkhathi, insimu yamagnetic, umsebenzi wezinkanyezi, i-geology, umjikelezo wekhabhoni, kanye nokuba khona kwamanzi.
Isinyathelo esilandelayo ukusesha ama-biosignatures asemoyeni. Ngokusebenzisa i-spectroscopy, ososayensi bazama ukuthola amagesi angabonisa umsebenzi wezinto eziphilayo, njenge-oxygen, i-ozone, i-methane, noma inhlanganisela yamagesi ekungalingani kwamakhemikhali. Kodwa-ke, inselele ibalulekile: izinqubo ze-geological noma ze-photochemical nazo zingakhiqiza la magesi. Ngakho-ke, izazi zezinkanyezi ziyaqaphela kakhulu ukugwema "izinto ezinhle ezingamanga" futhi zizama ukwakha imigqa eminingi yobufakazi ngaphambi kokufinyelela iziphetho.
Kuyini ukusayina kwe-bio futhi kungani kunzima?
I-biosignature iwumkhondo ongase ushiywe ukuphila—kungaba i-molecule yezinto eziphilayo, iphethini ye-isotopic, isakhiwo esincane kakhulu, noma ngisho nokwakheka komkhathi. Inkinga iwukuthi, imvelo ingalingisa nokuphila. Isibonelo, i-methane ingakhiqizwa ngamagciwane, kodwa ingavela futhi ezinqubweni ze-geological ezifana ne-serpentine (ukusabela kwamatshe namanzi). I-oksijini ingaba umkhiqizo we-photosynthesis, kodwa ngaphansi kwezimo ezithile, ingakheka ngokuqhekeka kwama-molecule amanzi ngemisebe, bese i-hydrogen ikhishwa emkhathini.
Ngakho-ke, i-astrobiology ithuthukise indlela eqinile: ukuhlukanisa izimpawu zezinto eziphilayo nezingezona ezezinto eziphilayo, ukuhlola imibono ehlukile, nokuhlanganisa idatha ye-geological, yamakhemikhali, kanye nemvelo. Empeleni, "ukuthola impilo" kuvame ukusho ukuqoqa ubufakazi obuqhubekayo, hhayi isilinganiso esisodwa, esiqondile.
Ukubaluleka kwe-astrobiology kubantu
I-Astrobiology ayigcini nje ngokuthi “ingabe bakhona abantu abavela kwamanye amazwe?” Ukubaluleka kwayo kubanzi futhi kungokoqobo.
1. Ukuqonda imvelaphi yethu. Ngokuhlola ukuthi ukuphila kwavela kanjani ezintweni ezingaphili, sijulisa ukuqonda kwethu ngokuziphendukela kwamakhemikhali kanye nezinto eziphilayo. Lokhu kusiza ekuphenduleni umbuzo oyisisekelo: yiziphi izidingo ezincane zokuqala kokuphila?
2. Umthelela kwisayensi yoMhlaba kanye nokushintsha kwesimo sezulu. Ukufunda ngezindawo ezizungezile zamanye amaplanethi kuthuthukisa ukuqonda kwethu ukuguquguquka kwesimo sezulu, umphumela wokushisa komhlaba, kanye nokuzinza komoya. Isibonelo esivamile yiVenus, enikeza isibonelo esibi kakhulu sokufudumala komhlaba. Isayensi yamaplanethi kanye ne-astrobiology inikeza imibono yokuqhathanisa yokuqonda uhlelo loMhlaba.
3. Ukushayela ubuchwepheshe obusha. Imisebenzi yasemkhathini idinga amathuluzi amancane, azwelayo angamelana nezimo ezimbi kakhulu. Intuthuko kuma-sensor, amarobhothi, ama-spectrometer, amasu okubulala amagciwane, kanye nokuhlaziywa kwedatha kuvame ukuthinta ubuchwepheshe eMhlabeni—kungakhathaliseki ukuthi kusemkhakheni wezokwelapha, wezemvelo, noma wezimboni.
4. Ukuziphatha kanye nokuvikelwa kwamaplanethi. Uma kukhona ithuba lokuphila kwama-microbial ku-Mars noma enyangeni ebandayo, khona-ke imisebenzi yabantu noma yamarobhothi kumele ivimbele ukungcola. I-Astrobiology iphakamisa imibuzo yokuziphatha: indlela yokuhlola ngaphandle kokulimaza imvelo yangaphandle (uma ikhona), kanye nendlela yokuvikela uMhlaba kumasampula angaba yingozi ngokwezinto eziphilayo.
5. Imibono yefilosofi namasiko. Umbuzo wokuphila ngale koMhlaba uthonya indlela abantu abazibheka ngayo. Ukutholakala kokuphila, ngisho nokuphila okunezinhlayiya ezincane, kungaba esinye sezenzakalo zesayensi ezibaluleke kakhulu emlandweni—izingxoxo ezishintshayo mayelana nokuhlukile koMhlaba, ukuziphendukela kwemvelo, kanye nendawo yethu endaweni yonke.
Ikusasa le-astrobiology
Emashumini eminyaka ezayo, i-astrobiology izoncika kakhulu ekubambisaneni okukhulu kanye nedatha eningi: ama-telescope anamakhono abukhali e-spectroscopic, imisebenzi yokubuyisa amasampula evela ku-Mars, ukuhlola izinyanga ezibandayo, kanye nokulingisa amakhompyutha kanye nobuhlakani bokwenziwa ukuze kuhlungwe izimpawu ze-biosignature.
Kodwa into eyodwa ihlala ingaguquguquki: i-astrobiology iyisayensi yamathuba. Idlula emngceleni phakathi "kwalokho esikwaziyo" kanye "nokungaba khona," ngokuqina okukhulu kwesayensi. Ngisho noma singakayitholi impilo ngale koMhlaba, i-astrobiology isalokhu iyigugu ngoba ithuthukisa ukuqonda kwethu ngokuphila uqobo—indlela okwavela ngayo, ukuthi kuqhubeka kanjani, nokuthi amathuba ayo asakazeke kangakanani endaweni yonke.
Ekugcineni, i-astrobiology ifundisa ukuthi impilo akuyona nje into eyenzeka ngebhayoloji, kodwa futhi iyinto eyenzeka endaweni yonke: ehlangene namatshe, amanzi, izinkanyezi, i-chemistry, kanye nobubanzi besikhathi. Futhi ngenxa yalokhu, ukuyifunda kuyindlela yokuqonda hhayi amazulu kuphela kodwa nemvelaphi yethu kanye nekusasa lethu eMhlabeni.
