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It appears that a body of liquid water has been found buried beneath layers of ice and dust on Mars' south pole. The discovery was made by the European Space Agency (ESA) using radar data collected during their Mars Express mission. Though the mission has been in progress since 2003, this is their first major piece of evidence that liquid water currently exists anywhere on the red planet. The discovery was made using MARSIS, the Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument, housed within the Mars Express orbiter. It found an especially bright radar reflection in the south polar region of Mars. The scientists believe this bright reflection, found 1.5 kilometers deep beneath layers of ice and dust, is an interface between frozen water and a stable body of liquid water. For MARSIS to be able to find a body of water like this, it would "need to be at least several tens of centimeters thick," “This is just one small study area," said Roberto Orosei, principal investigator of the MARSIS experiment. "It is an exciting prospect to think there could be more of these underground pockets of water elsewhere, yet to be discovered.” According to the BBC, the research team estimates that this area is between -10 and -30 degrees celsius, far below the regular freezing temperature for water. For this water to remain in a liquid state, the team believes that there are various salts saturating the liquid, keeping it from freezing over. Because of this possible presence of salt, chances are relatively low that carbon-based life lives within the water. However, there are some forms of microbial life that thrive in subglacial environments on Earth that are salt-laden, so it's not impossible. "It's plausible that the water may be an extremely cold, concentrated brine, which would be pretty challenging for life," said Dr. Claire Cousins, an astrobiologist. If scientists want definitive proof that this sort of microbial life exists, it is likely that they'll need to drill deep beneath the ice in order to collect samples of the liquid water. These findings come after last month's discovery by NASA that suggests past life on Mars. Colin Stevens is a freelance writer for IGN, and he still hasn't found definitive proof of intelligent life on Earth. Follow him on Twitter.
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Svi svjetski mediji danas su objavili veliku vijest da je na Marsu otkriveno jezero vode u tekućem stanju. Ono se nalazi na oko kilometar i pol ispod ju┼żne polarne ledene kape Crvenog planeta, a promjer mu je oko 20 kilometara. Otkriveno je pomoću instrumenta MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding), radara niske frekvencije na letjelici Mars Express Europske svemirske agencije (ESA) koja oko Marsa kru┼żi od 2003. Prema radu objavljenom u uglednom časopisu Science, podaci su prikupljani od svibnja 2012. do prosinca 2015. Oni su pokazali da je refleksija radarskih signala u području Marsa koje se naziva Planum Australe (što na latinskom znači Ju┼żna ravnica) značajno sna┼żnija, odnosno da je svjetlija, što je uobičajeno za vodene površine. Preduvjet za ┼żivot Otkriće vode va┼żno je prije svega jer je ona u tekućem obliku jedan od preduvjeta za postojanje ┼żivota negdje drugdje u svemiru budući da je temelj za funkcioniranje metabolizma ┼żivih organizama kakve poznajemo. A organizme s bitno drugačijom kemijom i ne mo┼żemo tra┼żiti jer ne znamo kako bi mogli izgledati i funkcionirati. Znanstvenici stoga već desetljećima tragaju za tekućom vodom na tijelima u Sunčevu sustavu i izvan njega. Na Marsu su ranije bili otkriveni tragovi erozije vode u tlu kao i tragovi mogućeg otapanja vode u ekvatorijalnim područjima tijekom ljeta. Također se pretpostavljalo da bi tekuća voda mogla postojati negdje ispod Marsove površine, a osobito ispod njegovih polarnih ledenih kapa. No ovo je prvo otkriće postojanja vode u tekućem stanju i to u obliku trajnog velikog vodenog tijela. MARSIS nije uspio utvrditi dubinu jezera, međutim znanstvenici smatraju da je ona najmanje jedan metar. "To naše otkriće je vodeno tijelo, jezero koje nije samo neka voda koja se otapa između kamena i leda, kao što se to na Zemlji zbiva ispod nekih ledenjaka“, rekao je prof. Roberto Orosei iz Talijanskog nacionalnog instituta za astrofiziku u Bolonji. "To je mjesto koje je vrlo obećavajuće za tra┼żenje ┼żivota na Marsu. No mi ne znamo pouzdano je li ono nastanjeno", dodao je.