Evidence For Liquid Water On a Frozen Early Mars

Matt_dk writes "NASA scientists modeled freezing conditions on Mars to test whether liquid water could have been present to form the surface features of the Martian landscape. Evidence suggests flowing water formed the rivers and gullies on the Mars surface, even though surface temperatures were below freezing. Dissolved minerals in liquid water may be the reason."

Warmer?

[mc1138]

Is it possible that mars was warmer at a time? Either with a high level of CO2 or some other greenhouse gas that would have warmed the surface enough for running water? Maybe a little more dramatic but maybe even a slightly closer orbit?

the next frontier

[IlluminatedOne]

We've so many things to learn from our red neighbor. I hate to put my tin foil hat on this early in the day, but I oft wonder how much data has been retrieved/analyzed/hypothesized upon that we (mouth breathers at-large) have not been made aware of. There are some tantalizing possibilities with Mars, both to learn of our past and to help forge our future. Like Buzz Aldrin, I think whomever the first Mars pioneers wind up being, they should not plan on returning...

Without giving the scientific method a nod, it easy to say 'of course there's water on Mars...duh!', but I still await the slam dunk chemical analysis. Too many things fool the eye from a distance, like so many men/women from across the room...

Coulda, woulda, shoulda

[elrous0]

Wow, another speculative article from someone one what COULD have been. I wish one of these days NASA would give me more than models, simulations, possibilities, and probes that are SUPPOSED to reveal actual conclusive evidence but which never do.

Re:Briny rivers

[Geoffrey.landis]

But if there was salt in the water, there was probably also life in that water. Life living in the salty water making it saltier by pissing in it every single day.

The thinking that brines may keep the water on Mars from freezing is not a new conclusion-- here ( http://www.liebertonline.com/doi/abs/10.1089/153110701753198927?cookieSet=1&journalCode=ast [liebertonline.com] ) is a discussion of the concept from a few years back.

And, of course, the fact that the Opportunity rover found the Meridiani Planum site to be covered with evaporite deposits (mostly sulfate salts) contributes a lot...

Re:Warmer?

[scorp1us]

The atmospheric composition of Mars is predominantly CO2 (95%). If you take some eco-nut stance, the warming is linear, if you take a better-modeled stance you'll find it is less than that. (Diminishes logarithmically)

The real question is one of geology. Was Mars' inner core capable of producing a protective magnetic should like the Earth's? Remember Mars is smaller and will therefore cool faster. Our core, as the theory goes is made by counter-rotating spheres of liquid iron. With this, comes a thick, rich and creamy atmosphere shielded from the solar wind by the magnetic field.

The other question is what was the older composition of the thick atmosphere. Mars has too much methane, allegedly. Both methane and water vapor are far better greenhouse gasses than CO2. (Terrestrially we worry about CO2, because it is our biggest byproduct of human activity, and is stable molecule that either needs a plant to make it into sugar, or the ocean to sink it to the bottom).

The surface of Mars can reach 25C from being heated by the Sun. So there is a decent amount of energy.

OPINION: There is enough evidence to suggest that Mars could have been roughly equivalent to tropical - humid and warm. Weather or not its breathable is a whole other story with all that supposed methane...

Re:Warmer?

[mc1138]

That's a good point about the core of the planet, I remember reading that only the Earth has the protective magnetic field. Is it possible, and this will draw on my real lack of geology, but would a shift in orbit, say a collision that formed the "moons" of Mars pushed it out, and had enough either change in temperature of maybe a collision itself was disruptive enough to stop it from working?

Re:Warmer?

[smoker2]

The only problem I can see with all your comments is that you are assuming this took place a long time ago. We know that Mars can reach the mid 20s C and we also know that there are massive periodic dust storms.
Don't you think the storms would have eroded away the water gullies, or at least filled them with dust by now ? So I would say the formations are a lot more recent than "in the ancient past when Mars had a bigger atmosphere".