Impaka hagati y’abemera ubuzima bwo hanze y’Isi n’ababihakana
Impaka ku buzima bw’ibivejuru, bwo hanze y’Isi(vie extraterrestre) zatangiye kera cyane mu mateka y’abantu uhereye mu gihe cy’abagereki ahagana mu kinyejana cya 4 mbere y’ivuka rya Yezu.
Zabayeho kubera kwibaza ku mwanya w’isi mu isanzure n’ukuntu ubuzima bushobora kubaho ahandi.
Nkubwo Abagiriki ba kera: Atomistes nka Epicure bavugaga ko hari izindi nyenyeri n’imibumbe ifite ubuzima, mu gihe uwitwa Aristote yabihakanye.
Mu gihe cy’Ubukirisitu bwo hambere, abantu bibazaga niba ubuzima bw’inyamahanga buhuye n’inyigisho z’iyobokamana.
Mu byiswe Copernican Revolution (mu kinyejana cya 16), Copernic yakuye isi ku mwanya wo kuba “mu ntebe y’isanzure ” ( centre de l’Unuvers) bituma abantu batangira kubona ko bishoboka ko ubuzima bushobora kubaho ahandi.
Naho muri iki gihe cya siyansi, impaka zishingira ku bushakashatsi bwa astrobiology, ariko nanone nta gihamya iraboneka ifatika ko haba hari ubuzima hanze y’Isi muri icyo gihe
Muri icyo gihe ariko nano Abashakashatsi benshi bemera ko ubuzima hanze y’Isi bushoboka.
Mu bushakashatsi bwa 2024–2025, hafi 87% by’abahanga bemeje ko ubuzima bw’ibanze bushobora kubaho mu isanzure, naho 67% bemera ko bushobora kuba burimo ibinyabuzima bikomeye, ndetse 58% bemera ko bushobora kubaho mu buryo bw’ubwenge buhambaye.
Dore rero impamvu abemeza ko ubuzima bushoboka hurya y’Isi batanga ndetse n’izo ababihakana batanga.
I.Impamvu z’abemeza ubuzima hanze y’Isi.
1. Ubunini bw’isanzure ( immensité de l’Unuvers)
Abahanga mu bumenyi bw’Isanzure bemeza ko Isanzure rifite galaxies zigera kuri miliyari ibihumbi bibiri ( 2 000 milliards) naho uw’inyenyeri bikaba bigoye kuwandika ni 3x 10exp22 ( 3 ikurikiwe n’amazeru 22). bikavugwa ko umubare w’izi nyenyeri uruta uw’utubuyenge tw’umucanga ( grains de sables) uboneka kuri plages ziri ku isi yose ungana 10exp 22.
Nko muri galaxie yacu: Voie Lactée (Milky Way), hari inyenyeri zibarirwa hagati ya miliyari 100 na 400.
Abashakashatsi rero ni aha bahera bemeza ko hari amahirwe menshi yuko hanze y’iyi Isi dutuye haba hari ibinyabuzima.
2. Ivumburwa ry’imibumbe igaragiye izindi nyenyeri.
Nkuko twabibonye Exoplanète ni ijambo rikoreshwa mu buhanga bwa astronomie risobanura imibumbe iri hanze y’urusobe rw’inyenyeri yacu (Système solaire), izenguruka izindi nyenyeri zitari izuba.
Ivumburwa ry’iyi mibumbe ni imwe mu mpamvu zikomeye zishyigikira ko ubuzima bushobora kubaho hanze y’Isi. Koko rero Exoplanète ya mbere yavumbuwe Mu mwaka wa 1992, abashakashatsi Aleksander Wolszczan na Dale Frail bavumbuye exoplanète ya mbere izenguruka inyenyeri ya pulsar (PSR B1257+12) naho mu mwaka 1995, Michel Mayor na Didier Queloz bavumbuye exoplanète ya mbere izenguruka inyenyeri isa n’izuba (51 Pegasi b). Iri vumbura rya nyuma niryo ryemejwe nka gihamya ikomeye ko imibumbe iri hanze ya Système solaire ibaho.
Abatanze iyi mpamvu bagaragaje ko inyenyeri nyinshi zifite exoplanètes ibi bigatuma amahirwe y’ubuzima ahandi hatari ku Isi aba menshi. Byongeye kandi zimwe muri izo exoplanètes ziri mu gace gashobora guturwamo (zone habitable) , aho bishoboka ko haba amazi mu buryo bw’amazi.
IFoto yakozwe n’umunyabugeni ishushanya exoplanete LP 791-18d iri hafi y’isi yacu ( 90 annees lumieres)
3. Ibaho rya Extrëmophiles
Extremophiles ni ni udukoko duto (micro-organismes) tubasha kubaho mu bice bisanzwe bizwi ko bitaberanye n’ubuzima ( conditions extreme), aho twatekerezaga ko ubuzima butashoboka.
Utu dukokora twavumbuwe bwa mbere mu myaka ya 1960–1970, ubwo abashakashatsi batangiye kubona ko hari mikorobe zibasha kubaho mu bice bikabije nk’amazi ashyushye cyane cyangwa ahantu hari acide nyinshi.
Ibyo byahindutse gihamya ikomeye ko ubuzima bushobora kwihanganira ibidukikije bigoranye guturwaho n’ibinyabuzima, bituma abantu batekereza ko bushobora kubaho no mu isanzure.
Urugero: Ubuzima bubaho mu mazi ashyushye cyane (hydrothermal vents), mu butaka bw’umunyu mwinshi, mu butaka bw’ubukonje bukabije, cyangwa mu bice bifite acide nyinshi.
II. Impamvu z’abahakana ubuzima bwo hanze y’Isi
- Ihurizo ( paradoxe) de Fermi
Paradoxe de Fermi ni ikibazo cyibajijwe n’umuhanga Enrico Fermi mu 1950 kugira kiti: “Niba hari amahirwe menshi bwo kubona ib’ivejuru , kuki tutarabubona?”
Koko rero Mu isanzure hari inyenyeri nyinshi cyane, zifite planètes zisa n’Isi. Ibi bituma abantu batekereza ko ubuzima bushobora kubaho ahandi.Ikibazo cya Fermi ni iki : Nubwo amahirwe ari menshi, nta kimenyetso na kimwe cyemeza ko hari ubuzima hirya y’Isi: nta signal, nta ingendo, nta ibimenyetso tubona.
Paradoxe de Fermi ntivuga ko nta buzima hurya y’Isi bubaho, ahubwo ni ikibazo cyibaza impamvu tutarabubona.
Iyi paradoxe yashyizwe mu mpamvu zihakana ibaho ry’ubu buzima kubera impamvu 2:
1. Iyi paradoxe ihinyuza impamvu zatanzwe n’abemeza ko ubwo buzima buriho harimo impamvu y’ubwinshi bw’inyenyeri.
2. Iri paradoxe niyo abahakana ubuzima hirya y’Isi baheraho batanga impamvu zabo ku kuba ubwo buzima budashoboka.
2.Hypothèse de la Terre Rare (Rare Earth Hypothesis)
Ni igitekerezo cyashyizwe ahagaragara n’abashakashatsi Peter Ward na Donald Brownlee mu gitabo Rare Earth: Why Complex Life Is Uncommon in the Universe (2000).
Ivuga ko ubuzima nk’ububoneka ku Isi ari ubuzima ubuzima bugoye cyane bushobora kuba ari buke cyane mu isanzure, kandi Isi ishobora ifite ibintu byihariye bituma ubuzima bushoboka.
Koko
– Imiterere y’inyenyeri
Isi iri hafi ya nyenyeri yacu (izuba) mu ntera ikwiye, ituma amazi aba mu buryo bwa liquide.
– Planète ifite umubumbe munini hafi
-Jupiter ikora nk’“umurinzi”, ikabuza asteroids nyinshi kugera ku Isi.
– Kuba dufite ukwezi kunini bituma isi iterera mu mihindagurikire y’ikirere.
– Plate tectonics
Imiterere y’ubutaka igenda ihinduka (tectonic plates) ituma isi igira ikirere gikwiye n’ubuzima burambye.
Hypothèse de la Terre Rare ni argument contre la vie extraterrestre kuko ivuga ko ibintu byose byihariye ku Isi bituma ubuzima bushoboka ku Isi bishobora kuba bitaboneka ahandi mu isanzure. Bityo, ubuzima bw’inyabwenge bushobora kuba ari rare cyane mu isanzure.