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Ancient Mars Ocean Found?
astroengine writes "With the help of rover Curiosity, we now know that ancient Mars had large quantities of liquid water flowing across its surface. However, evidence for large bodies of water — i.e. seas/oceans — has been hard to come by. But using high-resolution orbital data, Caltech scientists now think they've found a long-dry river delta that once flowed into a very large body of water. Welcome to the Aeolis Riviera — the strongest evidence yet for a Martian coastline. "This is probably one of the most convincing pieces of evidence of a delta in an unconfined region — and a delta points to the existence of a large body of water in the northern hemisphere of Mars," said Roman DiBiase, Caltech postdoctoral scholar and lead author of the paper that was published (abstract) in the Journal of Geophysical Research."
This is great news, not surprising, but great none the less. It's just that more evidence that Mars was a living, breathing planet, and might still be that way in some limited forms. Or perhaps not even all that limited if life on Mars never went beyond the microscopic form. But I'll get really excited and piss in my pants with giddiness if we learn that the transpermia theory has been confirmed and that life on Earth started on Mars. But that's a long, long way away.
It's really quite a simple choice: Life, Death, or Los Angeles.
Not all that flows is H2O. Not sure how they could determine the chemical composition of what formed these.
Yeah. But they also found blueberries. And blueberries need water.
3..
2..
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Actually there's plenty of evidence of water on Mars... get your facts straight.
Global warming is going to destroy the Earth's magnetic field or geodynamo? Is there anything global warming *can't* do?
One would expect a large body of water there. How the Universe Works "Extreme Planets" mentions a theory of Mars
being hit by an object moving the Northern hemisphere crust to the Sorthern hemisphere.
http://www.youtube.com/watch?v=N2t2VkDYOfYM#t=12m33 (12:33 in, link starts there)
I would assume leaving the Northern side lower as a result.
Not all that flows is H2O. Not sure how they could determine the chemical composition of what formed these.
Well, for that matter, the delta-like feature could have been sculpted by aliens. However, it's generally safe to rule out any absurdly unlikely reason when a far more likely one is available. There aren't a lot of candidates for alternate liquids to occur in large enough quantities at that location. In fact, I'm only aware of the one candidate, unless you want to resort to bonkers-level improbabilities (the chemical equivalent of "aliens did it")...
"Convictions are more dangerous enemies of truth than lies."
make ice cream.
No, I'm not kidding. It's really nice. It's the umpteemth conformation that Mars once had water. WE GET IT. MARS ONCE HAD WATER. Boots. Mars. Do it, NASA. This isn't rocket science.
Thanks Mars. Its back past gives a fair picture of the future Earth, thanks to global warming.
So you'll be riding a bicycle from now on?
Global warming is a lot like Jesus. True believers see them everywhere including things like toast, whereas normal people cannot.
Ahem, I hope your toast Jesus reference is frivolous. We all know the only true representations of Jesus are on tortillas.
http://www.google.com/search?q=jesus+tortilla&client=safari&rls=en&source=lnms&tbm=isch&sa=X&ei=1CjmUby8FYm9iwLCmYGADA&ved=0CAkQ_AUoAQ&biw=1586&bih=1008
Here's the obligatory XKCD reference.
Indeed. Just off the top of my head:
Gypsum sand and gypsum inclusions in rock strata.
Calcium and sodium perchlorate salts
Hydrated silica clay
All three of those require not just water, but often standing pools of water. The perchlorates especially, which at least on earth, form when salt water is slowly evaporated under exposure from strong UV radiation. Gypsum is a hydrated calcium sulphate salt, and requires liquid water to crystallize.
The hydrated silica clay can from just from ambient soil moisture working its magic on feldspar minerals, but usually requies active weathering. Like, rain.
As the parent said, there is ample evidence of water having been on mars. Lots of water.
Perhaps they are thinking of lava flows such as we have seen on the moon.
There's a bunch of hydrocarbons that form liquids at the temperatures found on mars. The atmosphere still contains traces of methane.
NASA Phoenix Mars Lander Confirms Frozen Water
... whatever
Maybe a subsurface probe that drills down where we expect to find liquid water, then to tests there? Maybe just dig a deep hole and test. Hell, set off a bomb if you have to. Our best bets are under the dirt now.
I swear to God...I swear to God! That is NOT how you treat your human!
I'd be interested in what other fluid could have carved the canyons and washouts that litter the surface of mars. Water is simple and very common. I'm not sure that there is enough liquid hydrocarbon out there to create these flow structures.
No volcanos here
If Mars used to be Class M, then sure it had roddenberries.
Its global CLIMATE CHANGE. And it leads to cooler winters. YOUR ICE CREAM HAS BEEN MADE. SIR
This is all caused by XKCD.
Support a Europe-related section on Slashdot!
That's the nice thing about a sample return mission like the one that's been proposed. It'll confirm your above opinion of the evidence. Something that looks like gypsum sand to a rover, may well be. But if it looks like gypsum sand in a lab on Earth, then that's a vastly more definitive piece of evidence.
No, because that CO2 is locked up in rock and if we manage to partly boil the oceans, we'll create a very efficient process for transferring heat to space while simultaneously getting rid of the cause.
Nothing like facts to destroy jokes...
So say we all
Doesn't it appear that the water would have been flowing upward, away from the lowest point on the lower part of the image. Assuming nothing changed that much since there was water, that seems really odd. It looks like the flowing sediment and stuff avoided the bottom part for no apparent reason. In every delta I've seen on Earth, it doesn't do that.
That's the nice thing about a sample return mission like the one that's been proposed. It'll confirm your above opinion of the evidence. Something that looks like gypsum sand to a rover, may well be. But if it looks like gypsum sand in a lab on Earth, then that's a vastly more definitive piece of evidence.
That's not really necessary as your situation isn't really possible.
Crystals/chemicals/etc don't really have many options to form 'differently'. When they form differently, they aren't the same. Sure you can get some isomers, but even then those don't necessarily have the same properties.
For your premise, that all of those minerals formed via some process other than one that involves water, would require a huge coincidence that the rover could somehow find all of these minerals which happened to form without water even though all of our experience tells us is unlikely.
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
Crystals/chemicals/etc don't really have many options to form 'differently'.
When you say 'differently', are you quoting someone? On Earth, we don't actually have this experience. There's a vast number of such chemicals and crystals formed under subtly different conditions and chemical composition. For gypsum, merely changing the quantity of water changes the mineral. We also can partly (not even fully) substitute other elements for calcium and sulfur to get new minerals.
For your premise, that all of those minerals formed via some process other than one that involves water, would require a huge coincidence that the rover could somehow find all of these minerals which happened to form without water even though all of our experience tells us is unlikely.
That's not my premise. We already know water exists on Mars. We see it directly in Mars's atmosphere. The polar caps show evidence of the presence of water ice. The previous poster asserted something stronger than merely the presence of water:
All three of those require not just water, but often standing pools of water.
and
As the parent said, there is ample evidence of water having been on mars. Lots of water.
Unlike Earth, there's been a very long time geologically to concentrate water in calcium sulfate, to create those perchlorates, and so on. We know the conditions are vastly different. I think it's a bit foolish to so confidently extrapolate from our limited experiences on Earth to that of Mars without acknowledging that we don't have supporting evidence for this sort of intuition.
Such undue certainty has been wrong in the past and it will be wrong in the future.
There's a bunch of hydrocarbons that form liquids at the temperatures found on mars.
At what pressure? This matters as much as temperature in determining the phase of a substance.
We send a rover to Mars. It picks up some rocks and does a few tests on them. Analysis can reveal the most likely liquids in which certain minerals will dissolve, re-crystallize and what sort of metamorphosis we are likely to find.
Have gnu, will travel.
steep land masses where contentnets used to rise out of the ancient oceans?
Yes, but give them a few million years of wind erosion after things dry out and their slopes will come to resemble dry land features.
Have gnu, will travel.
Given the similarity of mass between the moon and Mars, probably 1/6th pressure, assuming there was an atmosphere in the first place to keep it all there, which, as we see........
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
I'm tired of all the "water on Mars" reports. No jar of water, then NO WATER!
The joke wasn't even all that funny when it was new, and told by its originator.
7 centuries (or so it seems) of bastardization later, it's amazing that there are still those who think it makes them clever.
Alluvial deposits look nothing like lava flows.
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
Like the other poster said, not at the pressures you see on Mars, and not at normal temperatures. Ice can't even exist on the surface of Mars without sublimating away. If it occured in the past when atmospheric pressure was higher, then the temperature would have been higher from the greenhouse effect, meaning that it wouldn't be cold enough anyway.
Also, Mars has an oxidizing atmosphere, hence the red color. That isn't compatible with free hydrocarbons on the surface. That and you'd need a lot of hydrocarbons for an ocean. You only see that in the outer solar system where things are much colder.
Considering that Mars currently has loads of permafrost and current rock glaciers, as well as evidence of nearer-past glaciation, liquid water is a much more parsimonius answer.
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
What ever the pressure was before the atmosphere was torn away by the sun when it lost its magnetic field, providing it used to have one.
Planet mass doesn't have much to do with atmospheric pressure. Venus is around the size of Earth, yet the pressure is 90x higher on its surface.
Where's Helium around that delta?
mark "and is Dejah Thoris lounging by the Aeolian Riviera?"
There are (Titan rains methane, and has large lakes of ethane), just not on Mars.
Martian atmosphere resembles a colder version of what happened to venus's atmosphere. Venus likewise lacks a strong geomagneric dynamo. Some planetary scientists speculate that this is not because venus isn't heavy enough, but because the atmosphere is so hot, that mantle convection is not viggorous enough to create the dynamo. Mars just wasn't heavy enough, or cooled too signifigantly. Not enough data is available at this time. Regardless, both planets lost much of the lighter elements of their atmospheres to space from abrasive solar particle showers, due to both planets lacking a strong magnetic dynamo.
A significant portion of a hydrocarbon's mass is hydrogen, a light element that was blasted away from said atmosphere. Mars lacks the hydrogen needed to have large quantities of molecular hydrocarbons in its atmosphere. It has carbon dioxide instead.
Titan, being one of saturn's moons, is protected by the very powerful magnetic field produced by its parent, and has such retained all the hydrogen it sucked in during its formation in the early solar system. Its atmosphere does undergo reactions with highly energetic particles caught in saturn's ring system and magnetic field, but this only causes recombinations of molecules in its upper atmosphere, and causes it to appear more hazy, rather than it being blasted off into space.
Because of this, titan retains one of the thickest atmospheres for a body of its mass in our solar system, and does have liquid phase hydrocarbons of sufficient quantity to cause liquid erosion patterns on its "land masses". Mars simply does not.
Agree. i was just trying to answer the earlier question which was what other than H2O produces large flows. Personally i believe it was water but the only other large flows i have seen is lava. I agree it was not lava that did this.