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Researchers find methane on MarJanuary 16th, 2009 - 4:28 am ICT by IANS Washington, Jan 16 (DPA) A team of NASA scientists has found proof of the existence of methane gas on Mars, raising questions about the possibility of life on the red planet, the US space agency said Thursday. In an article published in the journal Science, researchers said they found seasonal variations in methane in the planet’s atmosphere that could be evidence of geological or biological processes. On Earth, 90 percent of the gas is produced by living things such as the fermentation of organic material or gas released by livestock, but geochemical processes also produce levels of the gas similar to those found on Mars, the scientists said. “Mars could be more active than we have long believed,” astrophysicist Geronimo Villaneuva told DPA in an interview before the findings were released. It is unclear whether the methane was produced by bacteria or from so called methane ice deposits, he said. “The question of the possibility of life on Mars is now asked anew.” Scientists monitored the Martian atmosphere using Earth-bound infra-red telescopes to look at 90 percent of the planet over three years, finding plumes of methane in 2003. More studies are needed to locate the source of the gas. “Methane molecules have a short life span in the Martian atmosphere. The discovery of larger quantities in recent years points to a current release process,” Villaneuva added. Last year, a NASA rover confirmed the existence of water on Mars, in a key finding that leaves open the possibility of past or present life there. - Methane in Mars' atmosphere lasts less than a year - Sep 21, 2010 - NASA spacecraft detects significant changes in Mars' atmosphere - Apr 22, 2011 - Rapid destruction of methane makes Martian environment too hostile to support life - Aug 13, 2009 - Unmanned aircraft to look for life on Mars - Nov 16, 2010 - Bad breath, fart sniffer to hunt for life on Mars! - NASA unveils compelling evidence of life on Mars - Apr 29, 2010 - Aliens exist on Saturn's moon: NASA - Jun 06, 2010 - Mars may be teeming with microbial life - Jan 15, 2009 - Ultra fast destruction of Martian methane spells bad news for life - Aug 06, 2009 - Methane on Mars traced to three hotspots - Jan 16, 2009 - Mars CO2 leak linked to existence of life - Oct 11, 2010 - Life on Mars found but destroyed by mistake - Apr 14, 2012 - Climatic conditions on early earth similar to current ones - Dec 01, 2011 - Traces of laughing gas could aid search for life on Mars - Apr 28, 2010 - Is Saturn's moon Titan home to some kind of exotic life form? Tags: astrophysicist, current release, earth bound, gas methane, geochemical processes, journal science, life on mars, life span, martian atmosphere, methane gas on mars, methane ice, methane molecules, nasa rover, nasa scientists, organic material, red planet, science researchers, seasonal variations, us space agency, water on mars
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PLANET Mars, koji se nakon slijetanja američkih istraživačkih robota Spirit i Opportunity nalazi u središtu pažnje mnogih, ako je vjerovati posljednjim rezultatima istraživanja, zaista bi mogao biti dom živim organizmima, javlja BBC. Naime, teleskopi sa Zemlje kao i letjelica Europske svemirske agencije Mars Express potvrdili su postojanje plina metana u atmosferi Marsa. Metan je inače otkriven metodom spektroskopije, koja detektira tzv. spektralni "potpis" metana. Životni vijek metana u atmosferi Marsa je relativno kratak (molekula metana je nestabilna na Marsu), pa je očito da na crvenom planetu postoje stalni izvori ovog plina. Kakve to veze ima s mogućim postojanjem života na Marsu? Postoje dva moguća objašnjenja za pronalazak metana u atmosferi Marsa. Jedan su aktivni vulkani, koji još uvijek nisu uočeni na Marsu, a drugi su određena vrsta mikroba koji sintetiziraju metan iz vodika i ugljičnog dioksida. U atmosferi Marsa nema kisika koji je potreban većini živih organizama, ali ne i dotičnim mikrobima. Iako brojne istraživačke sonde koje orbitiraju oko Marsa još uvijek nisu otkrile nikakav trag vulkanske aktivnosti, koja bi također mogla biti izvor metana, potvrda o postojanju aktivnih vulkana imala bi znatne implikacije na istraživanje o postojanju života na Marsu. Naime, ako pod površinom Marsa zaista postoje nakupine goruće lave, oslobođena energija otopila bi ogromne količine podzemnog leda čije je postojanje potvrđeno, što bi pak moglo stvoriti uvjete pogodne za održanje života na Marsu. Drugo objašnjenje su tzv. metanogeni, vrsta mikroba koja postoje na Zemlji i sintetiziraju metan iz molekula vodika i ugljičnog dioksida. Budući da metanogenima ne treba kisik (kojeg nema u atmosferi Marsa), neki znanstvenici smatraju kako bi upravo takvi mikrobi mogli postojati na Marsu. Uz dvije istraživačke sonde na površini i nekoliko letjelica u njegovoj orbiti, te moćne zemaljske teleskope usmjerene prema Marsu, crveni planet polako počinje otkrivati svoje tajne.