Water flowing on Mars surface? - article in "Nature"

[czokletmuss]

Dark streaks that hint at seasonally flowing water have been spotted near the equator of Mars. The potentially habitable oases are enticing targets for research. But spacecraft will probably have to steer clear of them unless the craft are carefully sterilized  a costly safeguard against interplanetary contamination that may rule out the sites for exploration.

River-like valleys attest to the flow of water on ancient Mars, but today the planet is dry and has an atmosphere that is too thin to support liquid water on the surface for long. However, intriguing clues suggest that water may still run across the surface from time to time.

Source: http://www.nature.com/news/water-seems-to-flow-freely-on-mars-1.14343

[MBobrik]

sorry to rain ehm .. snow some dry ice on your parade but this is most likely just sublimating carbon dioxide avalanches as it was the case with similar gullies before.

[maccollo]

sorry to rain ehm .. snow some dry ice on your parade but this is most likely just sublimating carbon dioxide avalanches as it was the case with similar gullies before.

These take place in the warmer portions of the planet, and according to a NASA press conference I watched called "active mars" it's to warm to be dry ice, and the most likely candidate is water.

http://www.ustream.tv/recorded/41577590

That being said, it doesn't appear actually flow on top of the surface but rather between the sand grains. If it is the case that it is actually water, then these might be a prime destination for the next curiosity rover in 2020

The precise mission details haven't been outlined yet but is roughly "rover should look for signs of past life, collect samples for possible future return to Earth, and demonstrate technology for future human exploration of Mars."

If this is indeed liquid water then I would say it is a prime candidate for both signs of past life and sample return.

Even if life died long ago, it's arguably one of the last places where it would die out that are accessible to rover without drilling meters into the ground.

Having a martian sample that has recently been in contact with liquid water seems like it would also be desirable.

Actually if the water is really close to the surface it might be possible to scope it up before it evaporates, the sealing it in a container and maintaining it's temperature and pressure until we can get our hands on it. That would be quite something.

Edited December 16, 2013 by maccollo

[-Velocity-]

How can we confirm what these are? To my knowledge, these RSL features only occur on steep slopes not accessible to rovers. What is the feasibility of creating a blimp to hover above one of these slopes and lower something to take a sample?

Actually, come to think of it, it would probably be a lot easier to send a rover up to the edge, and have some little robot repel/crawl down the cliff/slope on a very long tether till it reaches the RSL feature. That way you don't have to worry about a huge gas bag and windstorms. The rover could reel the little guy up when the sampling was complete.

Alternatively... just send some humans there.

[-Velocity-]

sorry to rain ehm .. snow some dry ice on your parade but this is most likely just sublimating carbon dioxide avalanches as it was the case with similar gullies before.

And the reason they slowly fade? And then return in the same spots again next year? They sure look like water, but sure- we need to a closer look to know for certain.

You know what they remind me of? When you're driving down the interstate, and pass through a hill that the construction crews cut through. In wet climes and times, there will be thin streams of water flowing down the rocky face of the cut-through hill, darkening the rocks.

Edited December 16, 2013 by |Velocity|

[Nibb31]

Alternatively... just send some humans there.

Or something like this:

[maccollo]

Alternatively... just send some humans there.

Climbing to reach locations inaccessible to rovers would be something humans can do. But with the current political climate manned exploration beyond LEO is apparently not something politicians want to deal with.

Like Obama's asteroid mission. It got derailed so fast it's not even funny.

"And by 2025 we expect new spacecraft designed for long journeys to allow us to begin the first ever crewed missions beyond the Moon into deep space. So we’ll start by sending astronauts to an asteroid for the first time in history."

Which turned into something like. "Oh you wanna go to an asteroid? Here's how you can do it without leaving geostationary space! Instead of going to a significant asteroid, we can take this tiny rock and bring it into lunar orbit"

But I digress, if you want to find something out about mars in the near future probes and robots is what we got.

Perhaps a smaller robot like this could be deployed by MSL next to the hill, and then it would walk up, take the sample and come back down again.

[KASASpace]

Or perhaps it's not water, maybe petrol? Anything, really. But the thing is, a human would need a hardy suit for that. You just can't have those fragile suits like Apollo, no sirree. So, maybe a probe, or perhaps a material scan from a distance, to figure out what it is? And how about robotic arms so probes can take surface samples, you know in KSP, and then you wouldn't NEED kerbals for that. But moving science around you would still need them......

[kiwi1960]

Mars has FOG..... I forget where I saw the article now, but that hints at water as fog is water vapour....

Given that any planet, except Earth, is an alien world, and we are only just learning about them, anything, I assume, is possible.

[MBobrik]

These take place in the warmer portions of the planet, and according to a NASA press conference I watched called "active mars" it's to warm to be dry ice, and the most likely candidate is water.

http://www.ustream.tv/recorded/41577590

If temperature rules out dry ice then water is really the best (perhaps only reasonable) explanation.

[-Velocity-]

If temperature rules out dry ice then water is really the best (perhaps only reasonable) explanation.

I donno. The simple fact of the matter is space exploration has taught us to expect the unexpected. There are geological processes that are occurring on the other worlds in the solar system that we simply haven't thought of yet or encountered, because they don't occur on Earth, and our imaginations are limited and colored by our experiences on Earth. We also don't have huge labs to simulate what the surfaces or subsurfaces of the other planets are truly like, and we couldn't even construct such labs because we don't actually know the conditions on the other planets in enough detail.

So, while I believe that water is likely to be the correct explanation, I'd still amend your statement to-

"If temperature rules out dry ice, then it's either water or some process we haven't yet encountered or imagined yet."

[Themohawkninja]

Water on Mars.

That is all.

[Themohawkninja]

Or perhaps it's not water, maybe petrol? Anything, really. But the thing is, a human would need a hardy suit for that. You just can't have those fragile suits like Apollo, no sirree. So, maybe a probe, or perhaps a material scan from a distance, to figure out what it is? And how about robotic arms so probes can take surface samples, you know in KSP, and then you wouldn't NEED kerbals for that. But moving science around you would still need them......

Oil is an organic compound. I'm pretty sure you can't make it without life.

[Drunken Hobo]

Liquid water on Mars isn't that crazy a concept. Gale Crater has sufficient pressure to maintain liquid water, as do numerous other impact basins. Near the equator the temperature regularly gets above freezing in summer, so why not?

Can't get stable bodies of water because of the UV radiation, but transient water underneath sand doesn't have such trouble.

[MBobrik]

"If temperature rules out dry ice, then it's either water or some process we haven't yet encountered or imagined yet."

that possibility is always there. no point mentioning it explicitly. "If the apple is falling, it's either gravity or some unknown process"...etc.

[Scotius]

Water on Mars.

That is all.

LOL. Thanks for a good laugh

[-Velocity-]

that possibility is always there. no point mentioning it explicitly. "If the apple is falling, it's either gravity or some unknown process"...etc.

Well, yes, but mostly no. You are missing an important distinction.

The reason the apple is falling we know for a 99.99999999999999999999999999% surety is because of gravity. This is because it is an environment and physics we are very familiar with. We can safely eliminate invisible pink unicorns as the reason for the apple falling.

However, if we spot something on Mars that looks like slopes darkened by water, we cannot say with a 99.99999999% certainty that it is water. Not even CLOSE. Why? Because we do not know enough about Mars yet. We know for a fact that Mars has geological processes we know nothing about, and we have not been monitoring Mars long enough, or collected enough data, to safely eliminate the possibility that this is just something that looks like water. So, you CANNOT say that water is the only reasonable explanation, because it is reasonable, given the limited nature of the observations so far, to suppose that there is a strong possibility of non-hydrological processes going on that merely mimic the look of water. However, you can safely state that water is our best explanation so far.

Edited December 17, 2013 by |Velocity|

[KASASpace]

Oil is an organic compound. I'm pretty sure you can't make it without life.

That's kinda the point.

Edited December 18, 2013 by KASASpace

[K^2]

Oil is an organic compound. I'm pretty sure you can't make it without life.

If you couldn't make organic compounds without life, where would life come from?

You just need hydrocarbons, heat, and pressure. I would be surprised if some amount of natural oil wasn't present on, say, Titan. (There's a though, maybe we can use that to convince US to send an exploration mission.)

That said, Mars isn't a particularly good environment for it, so yeah, it'd have to be extinct life. Which, still, isn't all that unlikely.

[Nibb31]

An oil baron's wet dream:

http://en.wikipedia.org/wiki/Lakes_of_Titan

[-Velocity-]

If you couldn't make organic compounds without life, where would life come from?

You just need hydrocarbons, heat, and pressure. I would be surprised if some amount of natural oil wasn't present on, say, Titan. (There's a though, maybe we can use that to convince US to send an exploration mission.)

That said, Mars isn't a particularly good environment for it, so yeah, it'd have to be extinct life. Which, still, isn't all that unlikely.

Well, I highly doubt that Mars ever had a biosphere thick enough to produce oil. Earth didn't either, not for the first 4 billion years of its existence.

[Simon Ross]

Another aspect to consider in the equation is that when we talk about water on Mars, it's probably not going to be the clean, pure liquid we commonly think of. Quite possibly it will be polluted with a number of different mineral contaminants that make it quite possible to remain in a liquid form even down to -20c