raw analysis of a martian meteorite that fell to Earth 13,000 years ago has revealed cue about prior habitableness on the red planet . The John Rock , which was reclaim from Antarctica 30 years ago , originated on Mars 4 billion twelvemonth ago , when piddle is believe to have underwrite the planet ’s open . Understanding the chemic composing of the rock will assist scientist determine if Mars could possibly have sustained life . Robina Shaheen of the University of California , San Diego is star author of the paper , which was published in theProceedings of the National Academy of Sciences .
" mineral within the meteorite bear a snapshot of the planet ’s ancient chemistry , of interactions between water and air , " Shaheen said in apress release .
The potato - shaped meteorite is formally known as ALH84001 , and is the oldest - known rock from Mars that we have witness on Earth . It was forge from the cooled magma of a vent , and trap samples of mineral and carbonates , providing a shot of ancient martian experimental condition .
The relative abundances of isotopes of atomic number 6 and oxygen from the martian atmosphere let the research worker to nail the specific composition signature that existed on Mars at the fourth dimension . While carbon dioxide dominates the Martian atmosphere , ozone is also present . However , the ozone is evenhandedly curious due to the heavy isotope of oxygen within it . These flakey isotope undergo a rare chemical substance response that imprints its chemical signature onto C dioxide .
" When ozone reacts with C dioxide in the atmosphere , it transfers its isotopic bizarreness to the newfangled molecule , " Shaheen explained .
This " weirdness " is also transfer when carbon dioxide and water create carbonate , leaving a very specific touch that can be detected . These stratum of eldritch isotopes can be used to set how much water may once have be on the planet , which could give clue about likely habitability . Small quantities of water supply would lead to big total of the odd isotope key signature , while large oceans would have a smaller signature . Ultimately , the chemicals discover within the meteorite do not propose that Mars hold the vast ocean that many believe once covered the ruddy major planet . Smaller body of piss are much more likely .
" What ’s also novel is our simultaneous measurements of carbon paper isotopes on the same sample . The commixture of carbon isotope intimate that the different minerals within the meteorite had separate origins , " Shaheen continued . " They recite us the story of the chemic and isotopic compositions of the atmospheric carbon dioxide . "
The outcome suggest that Mars ' atmosphere now has higher degree of carbon-13 than it did then . At the time , Mars had low levels of carbon-13 and larger levels of oxygen-18 . The change in piece of music are likely due to the bombardment experienced on the planet billions of years ago in plus to the loss of atmosphere .
regrettably , the carbonate discovered by the squad does not come along to have biological stemma , and these data did not give way any grounds of ancient Martian microbial biography . While NASA ’s Curiosity roamer did findtraces of methaneearlier this month , but this subject area was unable to corroborate those finding .
" We now have a much deeper and specific insight into the earliest O - water system system of rules in the solar system , " concluded co - source Mark Thiemens , also of UCSD . " The question that remain is when did planets , Earth and Mars , get water system , and in the case of Mars , where did it go ? We ’ve made great progress , but still bass mysteries remain . "
