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Mars Rover Sniffs First Hint of Water?
mhw25 writes "It is reported that the Mars rover Spirit is already well into its scientific mission, and may be detecting hints of water. The mini-Thermal Emission Spectrometer has returned its first image, with probable evidence of carbonates and hydrated minerals. We may know more after the rover rolls off its landing base, after making a 120 degree turn to avoid the airbag blocking its front ramp, to start analyses on soil from Thursday or Friday. An ongoing intrigue is already developing - a scientist reckoned that some of the soil around the airbag 'looks like mud, but it can't be mud'."
The low air pressure and the low temperatures in Gusev would seem to rule out liquid water. It's more likely (in my opinion) that what they're seeing is clay, which would have the water chemically bound. Although, as you stated, it's also possible that it's composed of statically-charged Martian fines.
and just a year ago we found out that both poles are mostly water ice.
-caf
It can't be mud because of physics. Water cannot exist in free form in the surface of Mars because it would simply evaporate instantly (at least in most locations). Temperature and atmospheric pressure are the usual suspects here. And we do know what those are with a relatively high degree of certainty. Ergo, it can't be mud. It must be some sort of wacky sand, like montmorillonite. Data from the Mariner probes has detected a few dozen types of this clay. Maybe this is one we haven't seen before.
Water, if found, will be either in the poles or trapped in molecule-sized amounts in rocks under the surface, nominally because of some sort of organism like microscopic algae or fungus keeps it there as part of its organic cycle. The idea goes that if you find water there you're also likely to find some type of primitive life.
But I suggest we let the thing dig holes and stuff before we get all excited =)
Last I heard they'd found bound water, and the surface was a lot hotter than they expected it to be. In the last image release I notice they show a graph of the temperature (presumably up near the Pancam) at ~1m above the surface - the great thing about Mars' atmosphere is how quickly it get's cold the higher you get - i.e. very. Like, your feet could be warm and your head would be a solid block of ice.
:)
The kinda cool thing is the TES data shows a current temperature map at surface level - you notice at Gusev Crater (where spirit is, about 15S, 185W - so basically around halfway down the right edge of the picture) the temperature is somewhere around 0C, +/-10 degrees or so.
The *really* cool thing is, when they were getting ready to make the rover stand up and strut its stuff, they went through extra checks and testing on Earth because the landing site was a lot warmer than they expected - there's every chance that it's above 0 there, in fact, there's every chance that (on the surface at least) Spirit is enjoying much better weather than I am right now.
It's common knowledge that Mars' equator regularly gets up into the positive numbers, even up above 20c, the only real question as to the feasibility of liquid water in these regions is whether there is any ice left there to melt, or if it is all up at the poles (or underground). Due to the low triple point of water on Mars, and the theory that it's just coming out of an ice-age, there's every chance there is no liquid left around there to melt, but there's certainly a chance there is.
Fortunately, we have a rover up there that will be able to tell us for sure in a few days
"Isn't that what commets are primarily composed of?"
Well, not exactly. Yes, water is present on comets. However, the H2O present on comets is primarily in a solid state. IOW, it's not fit to react with surrounding minerals (at least not in any sizeable quantities). So, yeah, it's perfectly reasonable to find trace amounts of water on Mars. However, the presence of large hydrated material deposits requires that this water be present in liquid form for relatively long periods of time.
That's misinformed, that's the temperature ~1m above the surface, the surface temperature does indeed rise above zero, and I believe has been since before Spirit landed
Real surface temp graph
What is THE best site for up to the minute reports?
I'd have to say Gusev Crater, but if you can't make it there, you could try this jpl (has all images & press releases) or this other jpl site (has more articles). Don't miss the 3D model they've built of the site
HIV Crosses Species Barrier... into Muppets
Great point: but the surface of Mars isn't just fine dry powders; it's fine dry powders in relatively low gravity. The behaviour of this isn't something we're familiar with and it may be that which is spooking the unnamed scientist.
Is the reason it "can't be mud" that it would have shown up as such in previous spectroscopic analyses from orbit?
Not this old argument again (referring to several of the above posts, but /. won't let me simultaneously reply to several).
The permanent Martian ice caps are just that, water ice. They expand and shrink seasonally, with much of the winter increase being CO2 ("dry") ice. In the Martian summers the poles are too warm for CO2 ice, in the Martian winters, too cold for some of the atmospheric CO2 not to freeze out. (So yes, at any given time, one pole is mostly water ice, the other mostly (covered with) dry ice -- except in spring and fall when the CO2 is changing poles -- which is also when you tend to get planetary dust storms. Imagine that.)
This has been more or less known since some astronomer first pointed a spectrometer at Mars, and largely confirmed by subsequent observation and exploration.
The only real discussion is the percentages of same, and how much (if any) water or water ice is in the soil further from the poles.
-- Alastair
Oh, PUHLEEEZE. Not more lame conspiracy theories. Heck, maybe the lander is just out in AZ somewhere, eh?
/. community ranged across the entire bell curve, but this is a new low, even for here.
If you REALLY believe that the US govt could maintain a fiction on such a scale, without word ever leaking, then my posting this is probably a waste of typing.
If you want access to the raw data streams, file a FOIA request. Or go build a 'scope and listen to them for yourself. You can be _pretty_ sure the latter signals aren't doctored. Unless, of course, all this 'data' was simply pre-programmed before launch, right?
I knew the
If you're not living on the edge, you're just taking up space!
Spaceflight Now also maintains good coverage and often posts the latest news even before the JPL weenies do.
You can see here that natural processes most likely have occured in a similar manner Mars as they do on Earth. The rover is going to check out these rocks tomorrow or the next day if all goes well. It is exciting to see discovery and the scientific process in action. Who knows maybe water is very common there and thats what eroded this hole into this rock. In any case, sooner or later we are going to turn up water on mars, find life, and reaffirm how precious life on earth in its abundance indeed is.
These will provide plenty of targets for the rover to study up close with its suite of instruments, which include a rock-grinder and microscope and a Mossbauer spectrometer.
Synopsis: There IS a microscope on Spirit.
There is a reason for everything. Sometimes that reason just sucks.
For whatever reason, NASA was reluctant to bake Pathfinder/Sojourner which landed in 1997 and instead baked bits and pieces (antennae, solar panels, parachute, etc.), and cleaned the rest (antibacterial windex, I guess) so that Pathfinder was "clean enough" - i.e., within the international guidelines.
I haven't found any info regarding the Spirit and Opportunity or the lost missions that may have impacted, however it's fair to assume that they, like Pathfinder and Mars Polar Lander (now in its own crater somewhere) went through some decontamination before launch, but Mars Climate Orbiter that burned on aerobraking gone awry was intended to orbit, not land, and may have not been so assiduously decontaminated. Like the famous Apollo example where astronauts retrieved a sneezed-on camera lens from a previous unmanned probe that still harbored some bugs, life is more hearty that we think.
Bush Lies On the Record.
Sorry, vacuum will not cause water to decompose into hydrogen and oxygen. It will remain water molecules, albeit very disperse ones. Breaking the molecular bonds between H and O in water requires an input of energy - electrical as in electrolysis or thermal - creating a dissociated plasma (very high temperatures). Vacuum is not sufficient to break molecular bonds.
This is what P-T diagrams are all about. Here's one for water. Note that there is a region where you can go straight from solid water (ice) to water vapor (steam) - sublimation. This is what would happen, in short order, to ice on mars. Unless, of course, it was bonded to soil or another molecucle (hydrous form) rather than being molecular water.
But I'm not a chemist...
I've been looking around various sites, but mostly keeping up with news about Spirit through google news. What is THE best site for up to the minute reports?
For news, status, updates, scientific info, images, video, and more, check out:
Mars Exploration Rover Highlights (AXCH).
This site has TONS of great links, animations, movies, cartoons, news, and everything else. I hit it and branch off from there many times a day.
Utter rubbish. Water doesn't dissociate into hydrogrn and oxygen just by being boiled. The interatomic forces holding the molecule together are not broken. You can make it dissociate by electrolysis but it does not happen through boiling. If it did it would be quite inadvisable to light a match anywhere near a kettle, given that a mixture of hydrogen and oxygen is just a bit flammable!
Each water molecule is polarised (quite strongly as it happens): although it is overall electrically neutral, one end is rather positive and the other end is rather negative. You get residual interactions between the positive end of one molecule and the negative end of the next one along. When the water molecules are extremely cold they are held in a lattice structure by these residual dipole moments. This is ice. When you add some heat the water molecules jiggle around, and eventually have enough energy to break the lattice and move around freely, though they are still attracted to each other because of the electrical dipoles. This is water. Add some more heat energy and the jiggling water molecules move so fast that they have enough kinetic energy to break out of the energy well of the intermolecular bonds. They can move around at will and each molecule can go where it wants. This is water vapour. The temperature at which these changes occur depends on pressure for reasons that you can go and look up.
What you see as steam when a kettle boils is actually liquid water that cools and recondenses into countless tiny droplets above the kettle's spout.
"'I pass the test,' she said. 'I will diminish, and go into the West, and remain Galadriel.'"
- JRR Tolkien.
carbon life needs water to form hydrocarbons which are the building blocks of the complex molecules of life.
its hypothesized you could base life on some other elements (like silicon), but since we've never seen it, we wouldn't even know *how* to look for it, much less recognize it if we did, short of a silicon based life form seen moving around...
-
Anyway, the quote was elicited only when one of the reporters there asked "to me it looks like mud, any chance it could be". The reply was that although it might look like mud, it couldn't be, followed by a description of the behavior of fine particles (they can flow, etc.).
I'd say that to use this as a quote that "scientists say" it looks like mud is a bit disingenuous.
Opinions my own, statements of fact may contain errors
You're on the right track. As I understand it from a Sedimentary Petrology course I took, we also classified material as mud based on the size of grains apparent. We use something called the Wentworth Size Class. Mud is generally composed of clay to silt sized grains which range anywhere from .00006mm - .0530mm in diameter. When these grains solidify, they form Mudstones, Claystones and Siltstones.
Mud traditionally implies an element of H20 though, so I think scientists would have to be somewhat anal about classifying it as such. The implications for saying water can currently exist at the surface of Mars is quite staggering for all sorts of scientific reasons.
Judging from the pictures (though I have nothing to scale it too), much of the material looks very very fine grained, in the realm of medium grained silt to clay sized particles. But without the presence of H20, that is all they are, just silt or clay (note, using the Wentworth Scale, clay indicates the finest grains).
Now the processes that created these fine silts and clays are very indicative of having sometime of wet environment that broke down materials into these fine grains.