A Cold and Wet History on Early Mars?
Written by Anne Minard
Mars. Credit: NASA
Even if an early Mars never got above freezing, the brine on its surface could have stayed liquid and supported life, a new study says.
Lead author Alberto G. Fairen, of NASA Ames Research Center in Moffett Field, California, and his colleagues have analyzed the behavior of Martian chemical concentrations found at various mission landing sites, and revealed that warm temperatures wouldn't have been necessary to support salt-loving life forms.
The authors point out that many features on the Martian surface are believed to have been formed by flowing water and related mineral activity on the surface. Water is a key ingredient for life, but models were having a hard time envisioning a Mars warm enough to support it.
Much evidence has indicated surface temperatures well below freezing.
According to the new study, life may have fared all right anyway.
"Solutes could depress the melting point of water in a frozen Martian environment, providing a plausible solution to the early Mars climate paradox," the authors write.
Fairen and his colleagues modeled the freezing and evaporation processes of Martian fluids with a composition resulting from the weathering of basalts, as reflected in the chemical compositions at Mars landing sites of Viking 1, Mars Pathfinder, and the rovers Spirit and Opportunity.
"Our results show that a significant fraction of weathering fluids loaded with Si, Fe, S, Mg, Ca, Cl, Na, K and Al remain in the liquid state at temperatures well below 273 K," or nearly 32 degrees Fahrenheit (zero C), they write.
"This stability against freezing of Martian fluids can explain saline liquid water activity on the surface of Mars at mean global temperatures well below 273 K."
Photo credit: NASA
Source: Nature
Filed under: Mars
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May 20th, 2009 at 12:24 pm
Didn't we already know that adding salts makes water freeze at different temps?? I don't see what's new here but I guess this is confirmation of theory?? It sounds like they have decided life is a forgone conclusion now too?? I think there's a good chance it's there but I haven't seen any new scientific evidence anywhere… I found this article confusing or missing some info?
May 20th, 2009 at 2:12 pm
Can we have a picture of the red plant to go with this article please?
May 20th, 2009 at 2:16 pm
Oops, sorry, browser problem – nice picture.
May 21st, 2009 at 5:21 am
Thats a fascinating picture of Mars, Those dark streaks across mars are so interesting.
Life on Mars? Now that theory allows for this possibility lets get out there and look.
I love the Rovers, but I have to say that ground crawling toys with limited range and scope just isn't going to do it. We need robots that can fly land, sample and analyze. (Base station with sample collectors?)
Same goes for the moon.
Why build a crawling wheeled machine in low or no gravity when you could fly?
Regards
Damian K
May 31st, 2009 at 4:04 am
absence of evidence does not equate to evidence of absence….