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User:Robertinventor/Simple animals could live in Martian brines - Extended Interview with planetary scientist Vlada Stamenković: Difference between revisions

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User:Robertinventor/Simple animals could live in Martian brines - Extended Interview with planetary scientist Vlada Stamenković (edit)

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<!-- details of atmosphere of Mars in http://science.sciencemag.org/content/341/6143/263 -->
[[File:Vlada Stamenković.jpg|thumb|left|Dr. Vlada Stamenković - planetary scientist at JPL and lead author of the paper. Wikinews interviewed him about the new Mars research via email.]]
The {{w|Atmosphere of Mars|atmosphere of Mars}} is far too thin for us to breathe, or indeed, for lungs like ours to extract oxygen at all. It has around 0.6% of the pressure of Earth's atmosphere, on average, mainly carbon dioxide; only 0.146% of that is oxygen. Yet the result of their modeling was clear. In the cold conditions on Mars these minute amounts of oxygen can get into the salty seeps of water which may be present there. What's more, the oxygen levels anywhere on Mars could reach the levels needed forto support microbial life that depends on oxygen.
 
Some life formsorganisms can survive without oxygen, but oxygen permits a more energy-intensive metabolism. Almost all complex multicellular life on Earth depends on oxygen. TheyThe foundcolder thatwater inis, saltythe watermore atoxygen theit coldercan conditionstake foundup. inIn the polarcoldest regionssalty water at the poles, perhaps 6.5% of the Martian surface, the oxygen levels can go far higher. Levels there may be enough even for simple animals such as sponges.
 
As interviewed by Wikinews:
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Some background may help before we get to the main interview with Vlada Stamenković.
 
'''''(background information):''''' You might wonder why they would research into these cold salty solutions. What about fresh water? Well, fresh water is likely to be rare on present day Mars., Overusually mostthe ofair thepressure surfaceis freshso low that water is not stable even at just above freezing, at 0&nbsp;°C. The higher pressure at the depths of the huge ancient impact crater of the {{w|Hellas Planitia|Hellas basin}}, do raise the boiling point of fresh water to 10&nbsp;°C, but that still means that fresh waterit is close to boiling point already at 0&nbsp;°C. If any ice melts, andthe water would evaporate away rapidly, afterindeed anythe pressure is so low that ice meltsisn't stable either at that temperature. <!--see Making a Splash on Mars-->
 
However, salty brines can be liquid at well below 0&nbsp;°C. These low temperatures also turn out to be ideal for taking up oxygen from the atmosphere.
 
Salts, and very salty brines cancounteracting alsothe taketendency inof the water fromto theevaporate atmosphereat low pressures, soand counteractingcan thetake tendencyin ofwater from the wateratmosphere totoo, evaporatein atthe lowprocess pressuresknown as deliquescence. They are especially good at doing this at low temperatures.
 
Curiosity discovered indirect evidence of this process in the equatorial regions (through humidity measurements). It is so dry that there isn't even any ice there, yet it found that brines form during winter nights in the top 15cm of the soil through {{w|Hygroscopy#Deliquescence|deliquescence}}. They take up water from the atmosphere at night when the salts reach temperatures of around -70&nbsp;°C. This water then evaporates again as the soil warms up through the day, and the process repeats every day - night cycle. <!-- "Evidence of liquid water found on Mars" in background information -->
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