Noi, Martienii


<Sci­en­tists are re­port­ing that the mo­lec­u­lar build­ing blocks of life formed on Mars long ago—find­ings that sug­gest these mo­le­cules could form on any cold, rocky pla­net.

Or­gan­ic molecules, con­tain­ing car­bon and hy­dro­gen, are the ma­jor com­po­nents of all Earthly life. In a new stu­dy, re­search­ers with the Car­ne­gie In­sti­tu­tion in Wash­ing­ton, D.C. an­a­lyzed or­gan­ic com­pounds in a Mar­tian me­te­or­ite. Sci­en­tists had pre­vi­ously spec­u­lat­ed that these might have land­ed on the red plan­et thanks to me­te­or­ite im­pacts there. The new study in­stead con­clud­ed that the ma­te­ri­als probably formed on Mars it­self, pos­sibly as a re­sult of vol­can­ic erup­tions.

The find­ings “show that vol­can­ic ac­ti­vity in a freez­ing cli­mate can pro­duce or­gan­ic com­pounds,” said the in­sti­tu­tion’s Hans Amund­sen, one of the re­search­ers. “This im­plies that build­ing blocks of life can form on cold rocky plan­ets through­out the Un­iverse.”

The in­ves­ti­ga­tors com­pared the me­te­or­ite, called Al­lan Hills 84001, with rocks from Sval­bard, Nor­way. These oc­cur in vol­ca­noes that erupted in a freez­ing Arc­tic cli­mate about a mil­lion years ago, pos­sibly mim­ick­ing con­di­tions on early Mars, the sci­en­tists said.“Or­gan­ic ma­te­ri­al oc­curs with­in ti­ny spheres of car­bonate min­er­als in both the Mar­tian and Earth rocks,” said An­drew Steele, lead au­thor of the stu­dy. The sci­en­tists, he added, found the or­gan­ic ma­te­ri­al in close as­so­ci­a­tion with a min­er­al called mag­netite—“the key to un­der­stand­ing how these com­pounds formed.”

When ma­te­ri­al blast­ed from Sval­bard vol­ca­noes cooled off, mag­net­ite acted as a cat­a­lyst, or chem­i­cal in­stiga­tor, for the forma­t­ion of or­gan­ic com­pounds from flu­ids rich in car­bon di­ox­ide and wa­ter, said the re­search­ers. “The si­m­i­lar as­socia­t­ion of car­bonate, mag­net­ite and or­gan­ic ma­te­ri­al in the Mar­tian me­te­or­ite... is very com­pelling,” they added in an an­nounce­ment of their find­ings Tues­day. “This is the first study to show that Mars is ca­pa­ble of form­ing or­gan­ic com­pounds at all.” The study is pub­lished in the Sep­tem­ber is­sue of the re­search jour­nal Me­te­or­it­ic & Plan­e­tary Sci­ence.
Steele said the work “sets the stage for the Mars Sci­ence Lab­o­r­a­to­ry mis­sion in 2009”—a NASA rov­er de­signed to help as­sess wheth­er Mars ev­er could, or can, sup­port mi­cro­bi­al life. One of its goals is to iden­ti­fy or­gan­ic com­pounds and their sources, said Steele, who i
s part of the mis­sion team. “We know that they are there. We just have to find them.”>


Acest articol, de pe world-science.net, vine in sustinerea unei teorii din ce in ce mai populare in lumea stiintifica. Unul dintre raspunsurile mai neobisnuite la intrebarea "cum a luat nastere viata pe Pamant?" este cel al panspermiei, care admite ca raspuns faptul ca viata s-a nascut de fapt pe Marte, cand aceasta planeta era mai tanara (acum 3 miliarde de ani), mai calda si cu apa in stare lichida. Dupa aceea, "aschii" din Marte au fost spulberate in spatiu ca urmare a impactului cu meteoriti iar unele dintre aceste aschii, devenite meteoriti, au ajuns in cele din urma pe Pamant, planeta cu conditii extrem de propice dezvoltarii vietii - mult mai bune decat cele de pe un Marte care incepea deja sa se schimbe catre un corp ceresc desertic, extrem de rece si lipsit de apa. Aceasta teorie e argumentata prin lipsa de dovezi solide, in momentul de fata, despre originea vietii pe Pamant, sugerand ca atata timp cat nu am gasit dovezi ce ar indica cum anume s-a nascut viata pe Terra, este rezonabil sa presupunem ca a luat nastere altundeva - iar Marte e un exemplu.
Articolul de fata sustine, oarecum mai modest, ca moleculele organice necesare formarii vietii provin de pe planeta rosie. Cu toate acestea, chiar si dovezile aduse de meteoritul AH80041 sugereaza ca pana la urma, chiar daca Pamantul era ideal pentru dezvolatrea vietii, aceasta s-a dezvoltat aici impulsionata sau chiar creeata de Marte.
Si daca teoria asta are dreptate, inseamna ca suntem cu totii martieni :) .

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