Rover Finds Ancient Streambed On Martian Surface

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Rover Finds Ancient Streambed On Martian Surface

Posted by samzenpus on Thursday September 27, 2012 @10:35AM from the low-flow-planet dept.

sighted writes "NASA reports that its Curiosity rover mission has found evidence that a stream once ran vigorously — and for a sustained amount of time — across the area on Mars where the rover is driving. There is, of course, earlier evidence for the presence of water on Mars, but NASA says this evidence, images of rocks containing ancient streambed gravels, is the first of its kind."

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Water, or some other fluid? by TWX · 2012-09-27 10:36 · Score: 4, Interesting

There are other fluids than water that can sustain a semicolloidal solution or carry sediments. I assume that scientists now have to figure out what fluid flowed, rather than simply assuming that it had to be water.

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1. Re:Water, or some other fluid? by jslarve · 2012-09-27 10:39 · Score: 5, Funny
  
  Probably never occurred to those rocket scientists and geologists at NASA. :)
2. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 10:42 · Score: 5, Insightful
  
  What else would it be besides water? Liquid Hydrogen?
  Considering the place were Mars occupies in our Solar System, I don't see how it could be anything other than water.
3. Re:Water, or some other fluid? by rubycodez · 2012-09-27 10:46 · Score: 4, Insightful
  
  it wasn't a liquid form of the atmosphere, carbon dioxide goes to solid. wasn't the 3% nitrogen, too warm. certainly not the argon, also too warm. maybe the NASA boffins know a bit more than you?
4. Re:Water, or some other fluid? by yincrash · 2012-09-27 10:48 · Score: 5, Interesting
  
  Both mercury and bromine could be liquid at reasonable temperatures. Both are also just as unlikely to be in amounts to have streams.
5. Re:Water, or some other fluid? by jhoegl · 2012-09-27 10:48 · Score: 2, Interesting
  
  Yes, but since humans havent been on Mars (that we know of), toxic sludge isnt one of them.
6. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 11:03 · Score: 5, Informative
  
  Hydrogen is the most abundant element in the universe and Oxygen is the third most abundant element in the universe. The only thing splitting them is Helium which is inert. All other things being equal the likelihood that a particular liquid at 'reasonable temperatures' is water is orders of magnitude more likely to be water than mercury or bromine.
7. Re:Water, or some other fluid? by ackthpt · 2012-09-27 11:03 · Score: 2
  
  There are other fluids than water that can sustain a semicolloidal solution or carry sediments. I assume that scientists now have to figure out what fluid flowed, rather than simply assuming that it had to be water.
  Zap it with a laser and conduct at spectrum analysis on it and see what elements pop up.
  
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  A feeling of having made the same mistake before: Deja Foobar
8. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 11:05 · Score: 1
  
  Does it even have to be a fluid? What about a flow of fine particles, or something like a pyroclastic flow?
9. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 11:08 · Score: 1
  
  It could be whiskey! (With an e because Mars isn't Scottish... or is it?!)
10. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 11:09 · Score: 1
  
  Yeah, the OP admitted that it probably wasn't mercury or bromine. C'mon my fellow AC, your making us look bad!
11. Re:Water, or some other fluid? by dreamchaser · 2012-09-27 11:10 · Score: 4, Insightful
  
  There are other fluids than water that can sustain a semicolloidal solution or carry sediments. I assume that scientists now have to figure out what fluid flowed, rather than simply assuming that it had to be water.
  I take it you've never heard of Occam's Razor. Given the composition of Mars and other evidence gathered to date water is by FAR the most likely substance to have caused this.
12. Re:Water, or some other fluid? by muon-catalyzed · 2012-09-27 11:19 · Score: 1
  
  Wouldn't make the liquid stones' shape oval, rounded, sand like gravel? These sharp edges, angled facets might be evidence of the very opposite.. but nice try NASA!
13. Re:Water, or some other fluid? by RabidReindeer · 2012-09-27 11:23 · Score: 5, Insightful
  
  There are other fluids than water that can sustain a semicolloidal solution or carry sediments. I assume that scientists now have to figure out what fluid flowed, rather than simply assuming that it had to be water.
  Zap it with a laser and conduct at spectrum analysis on it and see what elements pop up.
  Without proclaiming any expertise, I'd say that the erosion and eddy patterns left behind would be informative, since they would be indicative of the viscosity of the liquid. The pattern of sediment would drop hints towards its density. Water, CO2 and other highly-vaporous substances would not leave much, if any discernible residue or precipitate compared many other fluids. Some fluids would react with certain payload elements, other with different payload elements (in the structural meaning of the term "element", not the chemical one).
  There's a lot you can learn just ogling the pictures.
  THEN zap it with a laser!
14. Re:Water, or some other fluid? by ColdWetDog · 2012-09-27 11:30 · Score: 4, Insightful
  
  You're doing it wrong.
  Try looking at the closeup image. You know, the one that shows the nice, rounded stones. Just like the ones you'd find in a stream bed.
  
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15. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 11:32 · Score: 1
  
  Zap it with a laser
  I'd suggest to nuke it from orbit. That's the only way to be sure.
16. Re:Water, or some other fluid? by ackthpt · 2012-09-27 11:34 · Score: 1
  
  There are other fluids than water that can sustain a semicolloidal solution or carry sediments. I assume that scientists now have to figure out what fluid flowed, rather than simply assuming that it had to be water.
  Zap it with a laser and conduct at spectrum analysis on it and see what elements pop up.
  Without proclaiming any expertise, I'd say that the erosion and eddy patterns left behind would be informative, since they would be indicative of the viscosity of the liquid. The pattern of sediment would drop hints towards its density. Water, CO2 and other highly-vaporous substances would not leave much, if any discernible residue or precipitate compared many other fluids. Some fluids would react with certain payload elements, other with different payload elements (in the structural meaning of the term "element", not the chemical one).
  There's a lot you can learn just ogling the pictures.
  THEN zap it with a laser!
  Routinely you will find H20 bonded in some sediments where water has passed for a length of time, sans life, there will be less (to none) of the familiar compounds of Earth. It likely was water, but when and how much is certainly an interest, though it likely boiled off into space, thanks to Mars' weak gravity.
  
  --
  
  A feeling of having made the same mistake before: Deja Foobar
17. Re:Water, or some other fluid? by SternisheFan · 2012-09-27 11:39 · Score: 4, Informative
  
  Linked NASA photo's text:
  "Remnants of Ancient Streambed on Mars NASA's Curiosity rover found evidence for an ancient, flowing stream on Mars at a few sites, including the rock outcrop pictured here, which the science team has named "Hottah" after Hottah Lake in Canada’s Northwest Territories. It may look like a broken sidewalk, but this geological feature on Mars is actually exposed bedrock made up of smaller fragments cemented together, or what geologists call a sedimentary conglomerate. Scientists theorize that the bedrock was disrupted in the past, giving it the titled angle, most likely via impacts from meteorites. The key evidence for the ancient stream comes from the size and rounded shape of the gravel in and around the bedrock. Hottah has pieces of gravel embedded in it, called clasts, up to a couple inches (few centimeters) in size and located within a matrix of sand-sized material. Some of the clasts are round in shape, leading the science team to conclude they were transported by a vigorous flow of water. The grains are too large to have been moved by wind. A close-up view of Hottah reveals more details of the outcrop. Broken surfaces of the outcrop have rounded, gravel clasts, such as the one circled in white, which is about 1.2 inches (3 centimeters) across. Erosion of the outcrop results in gravel clasts that protrude from the outcrop and ultimately fall onto the ground, creating the gravel pile at left. This image mosaic was taken by Curiosity's 100-millimeter Mastcam telephoto lens on its 39th Martian day, or sol, ..."
18. Re:Water, or some other fluid? by chill13 · 2012-09-27 11:44 · Score: 1
  
  I didn't notice anything in the article estimating the age of the stream, but if it's in the order of billions of years, is it possible that Mars was in a different position at that time?
19. Re:Water, or some other fluid? by yotto · 2012-09-27 11:46 · Score: 1, Funny
  
  I take it you've never heard of Occam's Razor. Given the composition of Mars and other evidence gathered to date water is by FAR the most likely substance to have caused this.
  I bet it was Florida Orange Juice. Prove me wrong!
  
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20. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 11:49 · Score: 1
  
  There are other fluids than water that can sustain a semicolloidal solution or carry sediments.
  Could strong relentless sand storms do it? Does the fluid even need to be a liquid?
21. Re:Water, or some other fluid? by RicktheBrick · 2012-09-27 11:50 · Score: 2
  
  If it was water than there should be evidence of life even if it is only bacterial life. Even if they only discover bacterial life than some of these religious nut will have some explaining to do. We have been looking for life outside of earth for a long time now without success. I think if they do not discover some signs of either living life or past life than the whole mission will be a failure. It is just like looking for water on your property, one does not care how fancy or technological the equipment is, one only cares if they have found water. So I am hoping they discover signs of life soon.
22. Re:Water, or some other fluid? by dreamchaser · 2012-09-27 11:54 · Score: 4, Informative
  
  First, water is required for life as we know it, but the presence of water is no guarantee for life. Second, this is not a mission to determine if there are traces of life or not. Curiosity is mostly a geological mission, with an emphasis of finding out if there were ever conditions suitable to sustain life as we know it That's not anywhere near the same thing as finding proof there ever was or even if there still is life on Mars.
23. Re:Water, or some other fluid? by Tablizer · 2012-09-27 12:04 · Score: 2
  
  No, those flat rounded stones are the ones the Titanians tossed to watch them skip off of Titan lakes and on into space, toward Mars because of low gravity. Right diagnosis, wrong planet (or moon).
  
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  Table-ized A.I.
24. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 12:05 · Score: 0
  
  I think that's when the big astroid hit it and the martians fled to another galaxy.
25. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 12:07 · Score: 0
  
  Depends. At around 10 atmospheres and -65 degrees F, carbon dioxide most certainly would be a liquid.
26. Re:Water, or some other fluid? by SternisheFan · 2012-09-27 12:09 · Score: 1
  
  Curiosity's main mission...
  http://www.talknerdytome.net/2012/08/curiositys-main-mission.html?m=1
27. Re:Water, or some other fluid? by Tablizer · 2012-09-27 12:10 · Score: 1
  
  Thoat saliva is the next popular candidate among scientists.
  
  --
  Table-ized A.I.
28. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 12:14 · Score: 1
  
  So, drinking the water will give you a sore thoat then?
29. Re:Water, or some other fluid? by SternisheFan · 2012-09-27 12:19 · Score: 3, Informative
  
  Whoops! Curiosity's real main mission:
  "Curiosity’s primary mission will be to gather geological and environmental data from the Martian surface to determine whether the planet has ever offered environmental conditions favorable for life --and collect data for a manned mission. It will do this by travelling around a particularly promising site called Gale Crater, which has three miles of exposed geological strata, or rock layers like we have in the Grand Canyon. By drilling into these rocks and sampling them, scientists can tell quite a bit about global processes that formed the planet --including the role of water in its creation and the possibility of microbial life." http://energy.gov/articles/powering-curiosity-lab-tech-goes-mars
30. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 12:23 · Score: 4, Insightful
  
  What different position makes something other than water plausible? liquid forms of things we think of as "gasses" require it to be way out there, liquid forms of what we think of as "solids" require it to be way in there. There's a fairly small set of things liquid within the range of reasonable temperatures, and the obvious non-water choices are far more chemically complex.
  Granted, our understanding of mechanics of evolving planetary systems is rudimentary, theoretical, and subject to massive revision over the next decade as we observe more exoplanets, but Mars migrating that far while keeping its surface intact doesn't seem likely at present; while we should remain open to that possibility, Occam's razor says assume it's water.
31. Re:Water, or some other fluid? by PeanutButterBreath · 2012-09-27 12:24 · Score: 1
  
  I take it you've never heard of Occam's Razor.
  I've never heard of Occam's Razor. What is it? I'm imagining some kind of 7 legged, supersonic, invisible shoe.
32. Re:Water, or some other fluid? by dreamchaser · 2012-09-27 12:25 · Score: 1
  
  Pretty much what I said the first time...
33. Re:Water, or some other fluid? by poly_pusher · 2012-09-27 12:27 · Score: 1
  
  In another article they said it is likely thousands to millions of years old. I think this is being left out of some articles as it sounds absurdly broad for an estimate. However, not bad considering the Crater is estimated at 3-4 billion years old. I'm sure we'll hear more. They'll be pouring over ever ounce of data they can collect on this spot.
  
  This really is incredible. It's traveled less than 200 meters and found things worth studying. Once it gets to Glenleg things are going to get really interesting...
34. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 12:33 · Score: 1
  
  Depends. At around 10 atmospheres and -65 degrees F, carbon dioxide most certainly would be a liquid.
  Yeah, and then the only problem with that hypothesis is the 3 orders of magnitude discrepancy in pressure.
35. Re:Water, or some other fluid? by cbhacking · 2012-09-27 12:38 · Score: 2
  
  Considering that the atmospheric pressure on Mars is a lot closer to 100 milibars (1/10 of an "atmosphere") than to that of 10 [Earth] atmospheres, I think the GP's point stands. True, under certain conditions CO2 has a liquid state, but the liquid nitrogen is a far more likely explanation.
  
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36. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 12:45 · Score: 1
  
  Next the rover will find tall four-armed green men.
  Hopefully it will be able to send back some pics of them before they shoot it with their explosive rounds.
37. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 12:48 · Score: 1
  
  The onus to provide evidence is on the maker of the claim.
  What evidence can you provide that Mars once contained flowing rivers of pure Florida Orange Juice?
38. Re:Water, or some other fluid? by treeves · 2012-09-27 13:00 · Score: 1
  
  Yeah, maybe hydrazine or Dowtherm A or tetrahydrofuran or propylene glycol methyl ether acetate.
  
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39. Re:Water, or some other fluid? by NotQuiteReal · 2012-09-27 13:36 · Score: 1
  
  heh - "They'll be pouring over ever ounce of data they can collect on this spot." no pun intended? (see "poring" vs "pouring")
  
  --
  This issue is a bit more complicated than you think.
40. Re:Water, or some other fluid? by bromoseltzer · 2012-09-27 13:37 · Score: 4, Funny
  
  I've never heard of Occam's Razor. What is it? I'm imagining some kind of 7 legged, supersonic, invisible shoe.
  It's an Olde English Cellphone.
  
  --
  Fiat Lux.
41. Re:Water, or some other fluid? by pjbgravely · 2012-09-27 13:37 · Score: 3, Insightful
  
  Orange juice is mostly water, so water is still the correct answer.
  
  --
  Star Trek, there maybe hope.
42. Re:Water, or some other fluid? by Crypto+Gnome · 2012-09-27 13:54 · Score: 1
  
  Once they have some conclusive results I'm sure they'll be pouring ounces.
  
  Most likely the JD kind, though possibly one of the many "Hoot Mon!" brands.
  
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43. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 14:21 · Score: 0
  
  I take it you've never heard of Occam's Razor.
  Razors flowed on Mars? Let me be the first earthling to say, Ouch!
44. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 14:43 · Score: 0
  
  ... though it likely boiled off into space, thanks to Mars' weak gravity.
  I suspect that the low pressure atmosphere would be more of an influence on the water boiling off; of course, if it escapes the planet entirely after it's boiled into the atmosphere, that would be due to the low gravity.
45. Re:Water, or some other fluid? by l810c · 2012-09-27 15:50 · Score: 1
  
  THEN zap it with a laser!
  They didn't, they moved right along. This is one of the more interesting things I took from the NASA site.
  
  "A long-flowing stream can be a habitable environment," said Grotzinger. "It is not our top choice as an environment for preservation of organics, though. We're still going to Mount Sharp, but this is insurance that we have already found our first potentially habitable environment."
  There seems to be many steam beds in an alluvial plain. It's pretty clear that a liquid water river system once flowed there. You would think a river/stream system would be the ultimate place to start searching for life. But they seem to have a better target.
46. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 16:35 · Score: 0
  
  Bullshit. It was water, which proves there was life on Mars, that eventually got to earth on an asteroid, and led to life on earth. Can't you see the science?
47. Re:Water, or some other fluid? by Canazza · 2012-09-27 20:24 · Score: 1
  
  Mars is Ginger isn't it?
  (full disclosure: I'm Scottish, and not ginger)
  
  --
  It pays to be obvious, especially if you have a reputation for being subtle.
48. Re:Water, or some other fluid? by Canazza · 2012-09-27 20:25 · Score: 1
  
  also, the secret ingredient in Irn Bru is Martian soil.
  
  --
  It pays to be obvious, especially if you have a reputation for being subtle.
49. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-27 23:01 · Score: 1
  
  You don't even need additional structures (such as cross bedding) to figure that out, although I won't be surprised if they turn up those structures soon. The fact that the pebbles are rounded already implies a relatively low viscosity liquid like water. At higher viscosities the liquid would tend to cushion the pebbles and prevent the smaller ones from becoming rounded.
  An elemental analysis by itself won't tell you water was involved. But the presence of hydrated minerals such as clays would be pretty suggestive that it was available. Coincidentally there is remote sensing evidence (i.e. from orbit) that the mound of sediments Curiousity will eventually explore in the center of Gale Crater has hydrated minerals.
50. Re:Water, or some other fluid? by Dogtanian · 2012-09-28 00:42 · Score: 3, Funny
  
  Orange juice is mostly water, so water is still the correct answer.
  Human beings are mostly water, so I guess we can explain Mount Rushmore as "water erosion"? ;-)
  
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51. Re:Water, or some other fluid? by rwise2112 · 2012-09-28 01:14 · Score: 1
  
  Does it even have to be a fluid? What about a flow of fine particles, or something like a pyroclastic flow?
  True to a point, but these generally flow for a lesser distance and result in more angular particles.
  
  --
  
  "For every expert, there is an equal and opposite expert"
52. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-28 02:17 · Score: 0
  
  "Does it even have to be a fluid? What about a flow of fine particles, or something like a pyroclastic flow?"
  What do you think a pyroclastic flow is but a fluid?
53. Re:Water, or some other fluid? by tehcyder · 2012-09-28 02:25 · Score: 0
  
  Mars is Ginger isn't it?
  All the ginger girls I've ever met were full of moisture, and I 'm not talking about water, if you know what I mean. And I'm sure that you do.
  
  --
  To have a right to do a thing is not at all the same as to be right in doing it
54. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-28 02:31 · Score: 0
  
  Occam's razor says assume it's water.
  I'm sure I have always misunderstood this, but why does the fact that an explanation is the simplest of the ones available mean it is likely to be correct?
  
  I'm sure if you'd asked someone a couple of hundred years ago whether they thought Relativity and Quantum physics would turn out to be truer than Newtonian physics they'd have laughed.
55. Re:Water, or some other fluid? by Chris+Burke · 2012-09-28 02:33 · Score: 2
  
  They didn't, they moved right along.
  Well, a couple things to realize:
  1) They certainly did get a ChemCam measurement of at least a couple of the sedimentary outcrops -- definitely the Goulburn Scour at the landing site, and probably the Link outcrop. In the Raw Image archive it shows shots from the Cam part of ChemCam around the time they would have been departing Link, and those are used for context of what ChemCam is shooting. They've been shooting quite a bit of things with the laser, since it's "cheap".
  2) ChemCam isn't designed to find organics -- it does elemental spectroscopy, and any organics would be destroyed by the laser. And it's really best for giving you an idea of the predominant elements in a sample. John Grotzinger called it "qualitative", at least in comparison to the other instruments. Previous measurements of Goulburn showed composition consistent with the Martian basalt they see everywhere. So ChemCam measurements really don't add anything to the conclusion that water formed these sediments.
  To really determine if there are organics in the soil, they'll need SAM and Chemin. Those will come into play once they start using Curiosity's sample collection capabilities, which will be exercised soon at Glenelg (possibly before, but definitely during the months at Glenelg).
  
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  The enemies of Democracy are
56. Re:Water, or some other fluid? by MysteriousPreacher · 2012-09-28 02:43 · Score: 2
  
  If it was water than there should be evidence of life even if it is only bacterial life. Even if they only discover bacterial life than some of these religious nut will have some explaining to do.
  They're well practiced in explaining this kind of thing away. There's plenty enough evidence on Earth to question, if not completely contradict, some of their claims.
  
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  -- Using the preview button since 2005
57. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-28 02:46 · Score: 0
  
  Run mars. Run.
58. Re:Water, or some other fluid? by khallow · 2012-09-28 02:56 · Score: 1
  
  Carbon dioxide. Fluids don't have to be liquids.
  
  A continuous, amorphous substance whose molecules move freely past one another and that has the tendency to assume the shape of its container; a liquid or gas.
  If the stream bed is a billion years old and has carbon dioxide repeatedly flood it, it may well have well-worked stones like what are seen. Yes, I do think that the idea is something of a stretch, but it needs to be ruled out.
59. Re:Water, or some other fluid? by jrumney · 2012-09-28 03:10 · Score: 1
  
  Mercury would explain why the martians arranged those rocks to use as stepping stones to get across the stream. You wouldn't exactly want to get your feet wet in a pure mercury stream.
60. Re:Water, or some other fluid? by AllenABQ · 2012-09-28 03:38 · Score: 1
  
  Actually the new find only further confirms prior evidence that it was Dasani once flowed on the Red Planet. http://www.theonion.com/articles/cokesponsored-rover-finds-evidence-of-dasani-on-ma,1146/
61. Re:Water, or some other fluid? by Chris+Burke · 2012-09-28 04:13 · Score: 1
  
  Oh, and a couple relevant things I learned watching the news conference:
  John Grotzinger sounded a lot more open to the possibility of there being preserved organics in these rocks than in that quote, but noted that the presence of water over long periods could have also oxidized the organics into CO2.
  In response to Emily Lakdawalla's question specifically about whether they regretted driving on from this site without using other instruments, John said that having found several such outcrops so far makes them confident that they'll encounter more on the way to or at Glenelg (which promises to have other choices for materials to take samples from, too). And that if it turns out that they don't get any such opportunity, they can return to this site on the way back from Glenelg toward Mount Sharp (which is the significance of the name being a palindrome -- they'll pass it coming and going).
  
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  The enemies of Democracy are
62. Re:Water, or some other fluid? by monkeykoder · 2012-09-28 04:16 · Score: 1
  
  The rounding of rocks is usually due to rocks rubbing against each other carbon dioxide wouldn't be able to generate the necessary force unless it was moving at rather high speeds with higher densities than I (as a non-expert) doubt would be attainable on the lower gravity of Mars.
63. Re:Water, or some other fluid? by charlesj68 · 2012-09-28 04:42 · Score: 1
  
  Next the rover will find tall four-armed green men.
  If it's all the same, I'd rather it find and image Dejah Thoris ...
64. Re:Water, or some other fluid? by RockDoctor · 2012-09-28 06:03 · Score: 1
  
  If mercury were so common in the environment that it literally ran in rivers over the surface, then it's highly likely that the organism's physiology would have developed so that it wasn't concerned by the presence of the mercury.
  Physiologically, is iron a problem for us? Non-elemental phosphorus? Most sulphur compounds (in an oxygenic environemnt, where they oxidise to sulphites / suplhates)?
  
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65. Re:Water, or some other fluid? by RockDoctor · 2012-09-28 06:22 · Score: 1
  
  At the temperatures and pressures of the Martian surface (now, and at all times in all credible histories I've heard of) carbon dioxide is a gas not a liquid. You need 5+ atmospheres (half an MPa) to make liquid stable.
  Does that rule CO2 out as a possible fluid for you?
  
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  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
66. Re:Water, or some other fluid? by RockDoctor · 2012-09-28 06:32 · Score: 1
  
  This really is incredible. It's travel[l]ed less than 200 meters and found things worth studying.
  If you read around the original articles, they saw outcrops of these cemented conglomerates which had been scoured clear of dust and fine material by the blast of the SkyCrane's jets. While they were doing their pre-drive instrument check-outs.
  And they kept their communal traps shut until they'd found good enough evidence.
  
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67. Re:Water, or some other fluid? by Chris+Burke · 2012-09-28 06:47 · Score: 1
  
  I'm sure I have always misunderstood this, but why does the fact that an explanation is the simplest of the ones available mean it is likely to be correct?
  
  It doesn't.
  It does mean the simpler explanation should be preferred in the absence of any method of distinguishing, or absent any extra explanatory power by the more complicated explanation.
  In this case, water explains the composition of these rocks perfectly well. Other explanations could at best hope to explain such sediments as well as water, but would also create many more mysteries. We could conceivably find evidence of a non-water liquid carrier but in the absence of such water just makes more sense. We have a lot of evidence for water on Mars (including finding actual water ice in the present). So positing some other source of sedimentation just to arrive at a result equivalent to that of the obvious that Mars once had flowing water is, according to Occam, unjustified.
  Doesn't mean we can't/won't keep an eye out for signs that the simplest explanation isn't actually the best. But right now it is.
  
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  The enemies of Democracy are
68. Re:Water, or some other fluid? by RockDoctor · 2012-09-28 07:08 · Score: 2
  
  Does it even have to be a fluid? What about a flow of fine particles, or something like a pyroclastic flow?
  True to a point, but these generally flow for a lesser distance and result in more angular particles.
  Pyroclastics can flow for tens of kilometres, possibly a hundred kilometres (some of the Campi Flegrei pyroclastics around the Naples Metropolitan district have travelled approaching a hundred kilometres, and crossed passes of several hundred metres climb; "hmmm") though a few kilometres is more common.
  The internal structure of the particles in pyroclastic flows are generally noticeably vesicular. Vesicles are not reported, and I'd expect them to have been reported if they were seen. Also, typically, the clasts in pyroclastic flows are more angular than what I see in the pictures (though that is quite variable).
  Finally, the formation of pyrooclastic flows is quite strongly correlated with the chemistry of the magmas ; basalt is far commoner on the Martian surface, which would in itself argue against pyroclastic flows being common.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
69. Re:Water, or some other fluid? by RockDoctor · 2012-09-28 07:11 · Score: 1
  
  The erosive fluid at Mt Rushmore was mostly glycerine tri-nitrate, though adsorbed onto diatomaceous earth and packaged so that it appeared as a particulate solid.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
70. Re:Water, or some other fluid? by Anonymous Coward · 2012-09-28 07:21 · Score: 0
  
  Ammonia is not "far more chemically complex" than water. Slightly more complex, and also less likely given the prevalence of H and O over N, but not at all unreasonable as a possibility.
  - T
71. Re:Water, or some other fluid? by RockDoctor · 2012-09-28 07:51 · Score: 1
  
  If it was water than there should be evidence of life even if it is only bacterial life.
  
  By that measure, the gas clouds surrounding Eta Carinae should also contain life, despite being a hard vacuum (with water vapour) and UV radiation that would sterilize your skin (no easy task) before evaporating it.
  We hypothesise that water is essential for life. That does not mean that where there is water, there must be life.
  
  Even if they only discover bacterial life than some of these religious nut will have some explaining to do.
  
  Indeed they will. And I'll be up there demanding an explanation, now, not later.
  
  We have been looking for life outside of earth for a long time now without success.
  
  How long? 50 years (since the Drake Equation was proposed)? 60 years (since the enunciation of the Fermi Paradox)? 90 years (since Percival Lowell set up his observatory to map the Martian "canal" system)? Going back 110 years (Schiaparelli seeing what he interpreted as "channels") would probably be going a bit too far, as Schiaparelli wasn't really looking for life as such.
  That's not a "long" time. At the 90 year mark (which is very arguable), it's barely twice my lifetime (so far) ; my professional society is twice as old as that mark ; I aspire to be invited into a society 4 times as old ; I've participated in archaeological digs where I've excavated plough marks 45 times as old ; I've found archaeological material made by anatomically modern humans that is 60 to 90 times as old. I don't think that we've been looking for life for a particularly long time.
  
  I think if they do not discover some signs of either living life or past life than the whole mission will be a failure.
  The missions aims explicitly do not include finding life. Didn't you read any of the pre-landing material?
  
  It is just like looking for water on your property, one does not care how fancy or technological the equipment is, one only cares if they have found water.
  Sorry ; this is my territory. I drill oil wells for a living. It is 100% normal to be drilling a well for information. In the last year, 3 of the wells that I've drilled have been production wells, the other 4 have been for various types of geological information. OK - as a senior geologist with 25 years of experience it is possible that I get invited to work on more complex wells in more complex situations. But that's people spending serious money with no expectation of a producing well at the end of it.
  It is perfectly normal for the "drilling" people to be badgering me to find out if the wells is "a success" and if we've found oil. And they get deeply confused when I say "Yes, the well is a great success, and we've not found oil." But they don't pay my invoices ; the company's geology department pays my invoice (and all the rest of the well's bills) out of the exploration budget, and they're happy. So the well is a success : "plug and abandon ; dry hole."
  
  So I am hoping they discover signs of life soon.
  So do I. But I'm enough of a scientist to not expect it.
  I wonder if the bookies would take a bet on it? Put a fiver down, hope to get enough back for some decent bubbly if it pays off.
  Do you remember the ALH 86-001 kerfuffle? I said at the time that it would be the biggest thing since Copernicus / Galileo. Still waiting.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
72. Re:Water, or some other fluid? by whitroth · 2012-09-28 08:21 · Score: 1
  
  Maybe there was rain from galactic center....
  mark
73. Re:Water, or some other fluid? by whitroth · 2012-09-28 08:22 · Score: 1
  
  Let's try that again http //news.softpedia.com/news/Sagittarius-B-Contains-a-Billion-Billion-Billion-Liters-of-Alcohol-80786.shtml (Note the space replacing the colon after http)
74. Re:Water, or some other fluid? by whitroth · 2012-09-28 08:25 · Score: 1
  
  Dear dork:
  Do you actually know the meaning of the word "galaxy"?
  Do you also say that you've traveled to another continent when you go to the corner store?
  mark
75. Re:Water, or some other fluid? by Celarent+Darii · 2012-09-28 08:27 · Score: 1
  
  Mars looks almost orange in my telescope, undoutably because of all the orange juice.
76. Re:Water, or some other fluid? by RockDoctor · 2012-09-28 09:13 · Score: 1
  
  I've never heard of Occam's Razor.
  
  Your junior (7-10 age group, whichever country you're in) school teachers were incredibly negligent, or you were a stupid, inattentive pupil. Or you had some sort of attention-seeking disease. Or possibly you're under 7 years old (is there an age question on signing up for Slashdot - it's that long since I did it, I don't remember). http://en.wikipedia.org/wiki/Occam's_razor
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
77. Re:Water, or some other fluid? by RockDoctor · 2012-09-28 09:28 · Score: 1
  
  Could strong relentless sand storms do it?
  Not without leaving ventifacts.
  
  Does the fluid even need to be a liquid?
  No, it could (theoretically) be a gas, or a gas/ solid mixture (aerosol). Unfortunately, to generate a sufficiently high vertical component to the forces on the sediment grain (and so lift it in order to move it) , the lower the density of your fluid and the lower the viscosity, the higher the velocity you need. (I drill holes, horizontally, kilometres long, in rock, for a living. This is well supported experimentally.) Much higher velocities.
  So, you then have really high velocity winds, bearing sediment grains ; the smaller sediment grains impact on the larger ones which are just on the cusp of being picked up. Those are high-velocity impacts. The large, static grain gets abraded. That's a "ventifact".
  The gravel and cobbles pictured are rounded, not ventifact-shaped (bounded by multiple intersecting planes. That alone almost surely excludes a gas from consideration as a fluid phase.
  The poor sorting also excludes a gaseous fluid.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
78. Re:Water, or some other fluid? by TWX · 2012-09-29 12:31 · Score: 1
  
  Actually a friend of mine is Director for a space geology research and imaging archive facility at a major public university, and establishing what causes the appearance of flow patterns is very important to them.
  
  --
  Do not look into laser with remaining eye.
79. Re:Water, or some other fluid? by khallow · 2012-09-29 13:14 · Score: 1
  
  Does that rule CO2 out as a possible fluid for you?
  Gases are fluids as well as liquids.
80. Re:Water, or some other fluid? by khallow · 2012-09-29 13:22 · Score: 1
  
  The rounding of rocks is usually due to rocks rubbing against each other carbon dioxide wouldn't be able to generate the necessary force unless it was moving at rather high speeds with higher densities than I (as a non-expert) doubt would be attainable on the lower gravity of Mars.
  Carbon dioxide ice flashing to steam would be able to generate the necessary power. It would be necessary to demonstrate that the above process actually occurs enough to the same material to create worn pebbles.
81. Re:Water, or some other fluid? by RockDoctor · 2012-09-29 23:08 · Score: 1
  
  [SIGH] And you didn't see my other posting up-thread (or down-thread ; it's not clear on Slashdot's system) about why gaseous fluids would require far higher flow velocities and would therefore produce ventifacts rather than rounded pebbles.
  Sorry, I wrote it once and referred to it at least once again ; I thought I'd referred to it for you as well. Search the thread for "ventifact" ; it's not a common word, but in this context it is somewhere between highly appropriate and unavoidable.
  Your mechanism of "flashing" CO2 ice to vapour would produce an up-force. But how would you get a sufficiently rapid change of system properties to cause this to happen enough times to round off all faces of a pebble. One "flash" would propel the stone upwards, it'd land and chip off one projecting vertex. You'd need hundreds or thousands of "flashes" to produce a rounded pebble. Try running a "tumbler" for a while and see how long it takes to round off gravel and cobbles (technical terms). Your neighbours are likely to object because of the noise.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
82. Re:Water, or some other fluid? by khallow · 2012-09-30 17:21 · Score: 1
  
  Your mechanism of "flashing" CO2 ice to vapour would produce an up-force. But how would you get a sufficiently rapid change of system properties to cause this to happen enough times to round off all faces of a pebble.
  A lot can happen in a billion years.
83. Re:Water, or some other fluid? by khallow · 2012-09-30 17:48 · Score: 1
  
  To elaborate on my previous point, there are no analogous terrestrial processes to carbon dioxide-triggered landslides. My thinking here is a billion years of alluvial material slowly getting knocked around by many, many landslides generated by carbon dioxide flashing to gas.
  
  Ventifacts wouldn't be generated (or at least be a primary component) because most of the relevant erosion would be abrasion of rock against rock.
  
  Try running a "tumbler" for a while and see how long it takes to round off gravel and cobbles (technical terms).
  Not very long, if you ever tried it. Not sure what the point is here when Mars has a billion or more years to duplicate the erosion we can do in at most a few weeks of tumbling.
84. Re:Water, or some other fluid? by RockDoctor · 2012-09-30 21:18 · Score: 1
  
  My thinking here is a billion years of alluvial material slowly getting knocked around by many, many landslides generated by carbon dioxide flashing to gas.
  The debris movement of a landslide last for minutes to hours at best. It's not very effective at rounding off boulders. Having climbed through significant landslip deposits in caves and cave entrances, and over many landslip deposits in the Scottish highlands during my 6 weeks of compulsory (for my geology degree) geological mapping work and 30-odd years of recreational mountaineering, I can state that from personal observation.
  A landslip results in the movement of state from a position of high gravitational potential energy and low kinetic energy to a state of low(-er) gravitational potential energy and high(-er) kinetic energy. That kinetic energy is dissipated partly into fragmentation of the debris, but largely into heat.
  To repeat a landslip you either need to have additional removal of the topography to allow the material to fall again, or uplift of the material you wish to re-work.
  What is your mechanism for re-injecting the landslip material with sufficient CO2 to generate a second (third, fourth ...) landslip? This will then cycle back to the conditions that cause the landslip, and then repeat the cycle again. And again.
  The corresponding cycle of events for the "it's a liquid stream" interpretation is a water cycle not dissimilar to that operating on Earth today.
  
  To elaborate on my previous point, there are no analogous terrestrial processes to carbon dioxide-triggered landslides.
  You don't think that the outgassing viscous magmas collapsing and erupting from the flanks of a volcano are comparable? Each grain (sedimentological sense) of the material emits several times it's own volume of gases (water and CO2 primarily) while involved in a large (multiple cubic kilometre) landslip event. Review this video, particularly from about the 7 second mark when the "cockscomb" plume of a gas-evolving lateral blast becomes obvious. (Surtsey's phreatomagmatic eruptions have some similar effects.)
  I think such events are comparable (NB : "comparable" .NE. "identical") ; gas-fuelled pyroclastic eruptions are not renowned for their high grain rounding.
  Mars has been running erosive processes for billions of years, but most of them seem to have been moribund for the last 2 billion years. (Incidentally, when you're referring to modifying the surfaces of sediment grains, be they micron- or metre- scale, "corrasion" is probably a better term than "erosion". "Erosion" is normally something that happens to landscape and landforms.)
  Anyway, I've got to get floorboards ripped up to install cabling, so I'll be offline for the rest of the day.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
85. Re:Water, or some other fluid? by khallow · 2012-10-01 00:50 · Score: 1
  
  You don't think that the outgassing viscous magmas collapsing and erupting from the flanks of a volcano are comparable?
  Not at all. The mechanism here, if it exists, would be repeated freezing of CO2 in the soil and flashing into gas. There is no such mechanism on Earth comparable to that. It shouldn't need a large gradient (perhaps not any gradient at all, there might be a giant bowl of rounded gravel in the area that Curiosity is looking at, for example) any more than a stream does.
  
  Nor does the phenomenon need to happen today even. If the conditions were right for half a billion years for frequent energetic disturbance of gravel from CO2 outgassing, even though they aren't now, you'd still see much of what we do.
  
  Mars is remarkably Earth-like in its geological processes, but we need to remember that there will be big differences. I think atmospheric processes are going to be very different due both to the weaker oxidizing atmosphere (but it is still oxidizing with free oxygen, ozone, and perchlorates), far lower pressure (though that's about as high as it can get in the huge crater that Curiosity works in), and the particular physical properties of carbon dioxide (by far the principle component of the Martian atmosphere), including its relatively low melting point under pressure.
86. Re:Water, or some other fluid? by monkeykoder · 2012-10-01 08:11 · Score: 1
  
  The issue I see with this is not that it might not have enough force but the direction of the force seems like it would be in a radial direction from the center of the planet which would be unlikely to develop the rounded edges seen. It would also require flash sublimation which I don't have quite the background to have intuition about.
87. Re:Water, or some other fluid? by khallow · 2012-10-01 14:20 · Score: 1
  
  And what happens to the material that is pushed around? It's going to bounce and collide a lot and generate impacts, perhaps a considerable number per incident.
88. Re:Water, or some other fluid? by RockDoctor · 2012-10-01 21:23 · Score: 1
  
  You don't think that the outgassing viscous magmas collapsing and erupting from the flanks of a volcano are comparable?
  Not at all. The mechanism here, if it exists, would be repeated freezing of CO2 in the soil and flashing into gas.
  So you're looking to repeatedly put CO2 into the soil then release it abruptly. That doesn't sound very feasible to me.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
89. Re:Water, or some other fluid? by khallow · 2012-10-02 01:31 · Score: 1
  
  So you're looking to repeatedly put CO2 into the soil then release it abruptly.
  
  One such mechanism is the season cycle. CO2 freezes into the ground in winter and gets released in early spring whenever a drop in pressure occurs. Again, you're thinking about this in terrestrial terms.
  
  Keep in mind that Mars is currently just past fall equinox (September 29 according to the Planetary Society). Curiosity has yet to see any early spring phenomena.
90. Re:Water, or some other fluid? by RockDoctor · 2012-10-02 20:18 · Score: 1
  
  ... and in the Martian context, when CO2 freezes out of the atmosphere (which it does every Martian year), it forms a frost rather than penetrating into the sub-surface. So . . . what is your process for getting CO2 to penetrate into the subsoil, and then to change conditions (in the subsoil) so as to cause rapid outgassing. Then lather, rinse and repeat.
  Your fundamental problem is that your proposed mechanism requires repeated rapid changes in conditions in the subsurface, coupled with large fluxes of atmosphere through the soil.
  The proposed CO2 outgassing landslip scars in various parts of Mars are one-off events precisely because of the difficulty of recharging the subsoil with CO2. Feel free to try addressing that problem, because you won't be the only person by a long chalk to have looked at it. Then you might look at the question of how to cause a second (3rd, 4th ...) landslip in the debris deposited by a previous landslip. Landslip material comes to a stop precisely because it has come to an area of low potential energy.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
91. Re:Water, or some other fluid? by khallow · 2012-10-02 20:53 · Score: 1
  
  ... and in the Martian context, when CO2 freezes out of the atmosphere (which it does every Martian year), it forms a frost rather than penetrating into the sub-surface
  Based on what evidence? This is where your argument fails. Not only do you make an unverified claim for today, but also for the past billion or so years of that location.
92. Re:Water, or some other fluid? by RockDoctor · 2012-10-02 21:52 · Score: 1
  
  Go back and read your references on Martian atmospherics. The polar ice caps are mostly carbon dioxide with small amounts of water ice. That's been accepted for decades. Unless of course, you know better.
  HOW, precisely, are you proposing to get carbon dioxide FROM an atmosphere at a small fraction of a bar, THROUGH a soil of moderate permeability, AGAINST a temperature gradient (the surface cools by radiating into space ; the subsurface has a heat flux from the cooling interior), to then condense onto existing CO2 ice.
  Then, how are your conditions going to alter sufficiently rapidly to cause the CO2 you've accumulated over an extended period to flash into vapour.
  After that, explain how the subsequent landslips move this package of vapour-supported sediment from it's reduced slope to another location with an even further reduced slope. You're talking about multiply repeated landslip events affecting this particular unit of sediment ; and each landslip starts with a (relatively) high inclination landscape and turns it into a relatively low inclination landscape.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
93. Re:Water, or some other fluid? by khallow · 2012-10-03 01:26 · Score: 1
  
  HOW, precisely, are you proposing to get carbon dioxide FROM an atmosphere at a small fraction of a bar, THROUGH a soil of moderate permeability, AGAINST a temperature gradient (the surface cools by radiating into space ; the subsurface has a heat flux from the cooling interior), to then condense onto existing CO2 ice.
  
  Well, that sounds like a good start. Freeze CO2 out of the atmosphere in winter. Due to heating from the moderately permeable ground, CO2 vaporizes and refreezes further in the ground. Then in spring, sudden drops in pressure, say from a vaporizing layer of CO2 causes the occasional flash into vapor. Inclined landscapes might not be necessary.
  
  The problem isn't that this is implausible, but to show that it doesn't happen. You have a fair argument, but you don't have evidence to support it.
94. Re:Water, or some other fluid? by RockDoctor · 2012-10-03 18:02 · Score: 1
  
  Freeze CO2 out of the atmosphere in winter. Due to heating from the moderately permeable ground, CO2 vaporizes and refreezes further in the ground.
  Wrong direction. The ground is heated from below, or cooled from above ; pick an alternative and you get a gradient in the same direction. So, solid CO2 at (say) 20m below ground surface will have, generally, a HIGHER vapour pressure than solid CO2 at 10m below ground surface. So generally the heat flux from the ground will result in an outgassing flux from the soil.
  
  Then in spring, sudden drops in pressure, say from a vaporizing layer of CO2 causes the occasional flash into vapor.
  Wrong direction. In spring, as the Martian polar caps warm with approaching perihelion, the atmospheric pressure increases.
  
  You have a fair argument, but you don't have evidence to support it.
  I wish that I could say the same, but I think that you've got several effects operating with the wrong sign in your mental model.
  Anyway, I've got to bugger off now to attend a planning meeting for a 20-30 million dollar budget effort to investigate some ancient streambeds somewhere in the North West Europe Hydrocarbon Province. Which, considering the approaching winter season, could be "interesting".
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
95. Re:Water, or some other fluid? by khallow · 2012-10-04 12:43 · Score: 1
  
  So, solid CO2 at (say) 20m below ground surface will have, generally, a HIGHER vapour pressure than solid CO2 at 10m below ground surface.
  The location 20 meters down will also have a higher actual pressure due to the presence of 10 meters of overburden.
  
  Wrong direction. In spring, as the Martian polar caps warm with approaching perihelion, the atmospheric pressure increases.
  Warmth. That increases the vapor pressure of CO2 near the surface. As it evaporates, you have less pressure on deeper CO2.
  
  Anyway, I've got to bugger off now to attend a planning meeting for a 20-30 million dollar budget effort to investigate some ancient streambeds somewhere in the North West Europe Hydrocarbon Province. Which, considering the approaching winter season, could be "interesting".
  Why waste the effort? Just toss it on Slashdot. There's a lot of people who say that they know what they're talking about.
96. Re:Water, or some other fluid? by RockDoctor · 2012-10-05 10:16 · Score: 1
  
  The location 20 meters down will also have a higher actual pressure due to the presence of 10 meters of overburden
  
  Only if the overburden has effectively zero permeability and the pore-filling material is supporting the overburden with no remnant matrix stress. Which, as you'll know from your well-control courses and pore-pressure analysis experience. They are rather important things, as BP found out a couple of years ago (and on the back of which, I got about 5 months of work in Canada ; interesting but not particularly lucrative).
  But you very explicitly want your overburden to have permeability (so that the carbon dioxide can get into the formation from the atmosphere). So, the increase in pressure on the pore fluids will be the integral of the density of the pore fluid with the vertical distance into the sediment. (Normally you'd express as the product of the density and the vertical distance, but that only really works if you know or assume that your pore fluids have uniform density, or you're talking about your drilling or completion fluids, which bloody well better have uniform density or the mud engineer has got some explaining to do.)
  Anyway, if you want to be able to move CO2 into the sediment, then you've got to have hydraulic communication to the atmosphere. which means that the overburden is supported by stress in the sediment grains and the pressure of the pore fluids is the atmospheric pressure at the sediment-atmosphere interface plus the integral mentioned above. This really is basic pore pressure work - I've had to train a few dozen Applied Drilling Technology Engineers, Wellsite Geologists and Operations Geologists, for about a dozen companies (contractors and operators) in it after their first couple of years out of university, and it's been a routine part of my work for nearly 25 years.
  
  Warmth. That increases the vapor pressure of CO2 near the surface. As it evaporates, you have
  
  a net force on the newly evaporated CO2 (the vapour pressure of the evaporating CO2 on one side of any particular unit of gas, opposed by the general atmospheric pressure acting on the other side, giving a net force away from the evaporating solid CO2) ; that net force accelerates the mass of gas AWAY from the evaporating solid. So, bye bye CO2, and an infinitesimal increase in the general atmospheric pressure.
  You're talking about fluids of very low stiffness ; the only way that they can support a significant pressure differential is through their density acting over a vertical distance.
  
  There's a lot of people who say that they know what they're talking about.
  Some of them do. Many are bullshitters, but some do actually know what they're talking about. And when you're talking about your client's money, you do think quite hard before tossing it away. They tend to ask you why you did that, and then check if your answers add up. Funny that, you'd almost think they gave a shit about their money.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
97. Re:Water, or some other fluid? by khallow · 2012-10-05 13:16 · Score: 1
  
  Only if the overburden has effectively zero permeability and the pore-filling material is supporting the overburden with no remnant matrix stress.
  Well, the obvious sealant to consider here is frozen CO2. If we grant your assertion that it is impossible for CO2 to move into soil as I speculated above, there's still other ways to do it. For example, if the outgassing is strong enough to create craters or crevices, then one can have an alternate means of introducing frozen CO2, Namely, have it freeze into the surface of the hole and covered later by windblown sand. Similarly, a sand dune which moves in the direction of a mostly shaded side, could bury frozen CO2.
  
  Alternately, wind erosion might just work differently on Mars for this size or composition of pebble than anything we've experienced on Earth. Perhaps it was rounded while rolling along the surface of sand dunes at some point in the distant past. Sand effectively is acting as yet another fluid here both in the sand dune and as particles suspended in the wind.
  
  As I see it, there's simply too much we don't know about Mars and its past to rule out exotic processes unknown or rare on Earth. My take is that we will find that CO2 and its peculiar physical characteristics will result in some bizarre geological processes that are unheard of on Earth. Rounding pebbles without the use of liquid water may be one such process.
98. Re:Water, or some other fluid? by RockDoctor · 2012-10-06 05:53 · Score: 1
  
  Namely, have it freeze into the surface of the hole and covered later by windblown sand.
  Which does not describe the tabular nature of the deposit in question. So, it's relevance to the deposit in question is ... ?
  Rounding pebbles could happen without the presence of liquid water. It can happen dry ; it can happen in liquid hydrocarbons ; it can happen in liquid CO2, I'm sure ; it can probably happen in liquid fluorine ; but it would take time to happen, even in the liquid fluorine. Of those liquids, the most credible on in a previous Martian environment is, by far, the liquid water.
  Dry flow would require repeated rejuvenation of the slope to keep the sediment on the move, on a slope of around 30degrees to the horizontal.
  Liquid hydrocarbons would require some pretty exotic chemistry to have happened on Mars, for which there is no other evidence.
  Liquid CO2 would require an atmospheric pressure of around 500 times the present, for which there is no evidence (nor enough CO2 on the planet).
  Occams razor strongly suggests liquid water to be the most credible option for the fluid involved.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
99. Re:Water, or some other fluid? by khallow · 2012-10-06 13:10 · Score: 1
  
  Occams razor strongly suggests liquid water to be the most credible option for the fluid involved.
  Occam's razor suggests waiting for evidence rather than jumping to conclusions.
Re:Rocks by Anonymous Coward · 2012-09-27 10:52 · Score: 4, Insightful

So we spend billions to look at dirt !!
Look, touch, analyze. It sure beats sending 2-3 meatbags on Mars to do the same thing.
Good thing we didn't land then... by ackthpt · 2012-09-27 11:00 · Score: 2

Rover could have been washed away.
Launch, fly 54.6 million kilometers, land, drown. No profit in that.

--

A feeling of having made the same mistake before: Deja Foobar
1. Re:Good thing we didn't land then... by Crypto+Gnome · 2012-09-27 13:48 · Score: 1
  
  Launch, fly 54.6 million kilometers, land, drown. No profit in that.
  Conclusive proof of the existence of large amounts of liquid water on Mars would be absolutely worth the expense.
  
  --
  Visit CryptoGnome in his home.
Re:Rocks by multiben · 2012-09-27 11:03 · Score: 1

I know you're probably trolling, but if that is really your point of view then there maybe better places for you to hang out on the internet.
Re:Rocks by ackthpt · 2012-09-27 11:04 · Score: 1

So we spend billions to look at dirt !!
On Soviet Red Planet water finds YOU!

--

A feeling of having made the same mistake before: Deja Foobar
Re:Rocks by Capt.DrumkenBum · 2012-09-27 11:04 · Score: 2, Funny

It sure beats sending 2-3 meatbags
I believe those meatbags are commonly referred to as: "Ugly bags of mostly water"

--
If I were God, wouldn't I protect my churches from acts of me?
Soil. by mosb1000 · 2012-09-27 11:05 · Score: 1, Informative

It's called soil. Dirt is the stuff stuck on the bottom of your shoes.
1. Re:Soil. by Anonymous Coward · 2012-09-27 11:28 · Score: 2, Informative
  
  no, soil contains organic remains. dirt and regolith do not.
2. Re:Soil. by Hatta · 2012-09-27 11:42 · Score: 0
  
  It's the same stuff. Where do you think the dirt on the bottom of your shoes comes from?
  
  --
  Give me Classic Slashdot or give me death!
3. Re:Soil. by thexile · 2012-09-27 14:56 · Score: 0
  
  or vagina.
4. Re:Soil. by mosb1000 · 2012-09-27 15:46 · Score: 2
  
  I don't believe there is any requirement for soil to contain organic remains.
5. Re:Soil. by Anonymous Coward · 2012-09-27 17:04 · Score: 0
  
  So far as I have seen, "soil" refers to any sort of more or less loose stuff sitting on top
  of bedrock.
  From Dictionary.com:
  "1. the portion of the earth's surface consisting of disintegrated rock and humus."
  From Wikipedia:
  "Soil is a natural body consisting of layers (soil horizons) that are primarily composed of minerals which differ from their parent materials in their texture, structure, consistency, colour, chemical, biological and other characteristics. It is the unconsolidated or loose covering of fine rock particles that covers the surface of the earth.[1] Soil is the end product of the influence of the climate (temperature, precipitation), relief (slope), organisms (flora and fauna), parent materials (original minerals), temperature, and time. In engineering, soil is referred to as regolith, or loose rock material. Strictly speaking, soil is the depth of regolith that influences and has been influenced by plant roots and may range in depth from centimetres to many metres."
  From NSW TAFE Landcare notes:
  "Soil is a natural body consisiting of sopilds (minerals and organic matter), liquid, and gases
  that occur on the land surface"
  So they indicate organic matter as a necessity, but OTOH one hears references to the
  "Lunar soil", "Martian soil", etc, even if they are otherwise called regolith or sand.
  But they're free of organics at least those made by life.
  Of course on Earth all soils DO contain organic material, even if in tiny amounts like in deserts (Atacama, etc).
  "Soil" in these contexts might be loose language, or maybe we have to redfine it now we're digging on other planets..
  "Regolith" is in fact the bottom-most layer of many soil systems, and may be the "only" layer.
  "Dirt" is a hopelessly vague term. I'm pretty sure general purpose "dirt' contains organic gunk :)
6. Re:Soil. by tehcyder · 2012-09-28 03:07 · Score: 1
  
  It's called soil. Dirt is the stuff stuck on the bottom of your shoes.
  Isn't saying "dirt" (for soil) just a colloquial US usage?
  
  --
  To have a right to do a thing is not at all the same as to be right in doing it
7. Re:Soil. by RockDoctor · 2012-09-28 09:36 · Score: 1
  
  ITYM "parochial" not "colloquial", but yes, it is pretty much a EN_US-ism.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Re:Rocks by Anonymous Coward · 2012-09-27 11:11 · Score: 1

So we spend billions to look at dirt !!
Yes. That's why wine tastes good, and fewer houses are sliding off their foundations these days.
Just going to post the only thing worth posting by Anonymous Coward · 2012-09-27 11:20 · Score: 1

Neat.
1. Re:Just going to post the only thing worth posting by Tablizer · 2012-09-27 12:29 · Score: 1
  
  It's interesting the sucker practically just landed and barely started roving, and Kazaam!; there's a major discovery at the first rock grouping it encounters.
  I suppose this is similar to Opportunity in that it found bedrock and BB-sized metal spheres almost immediately.
  Both sites looked interesting from orbital observations. But then again, so did Spirit's, yet Spirit had to rove for several months toward the hills before it found anything sufficiently new.
  
  --
  Table-ized A.I.
2. Re:Just going to post the only thing worth posting by tehcyder · 2012-09-28 02:58 · Score: 1
  
  It's interesting the sucker practically just landed and barely started roving, and Kazaam!; there's a major discovery at the first rock grouping it encounters.
  * puts on tinfoil hat *
  
  Yes, it's very, um, interesting indeed.
  
  Of course the left-leaning hippies in NASA would have to come up with something interesting in order to justify their vast taxpayer-funded subsidies, funds which have been literally stolen AT GUNPOINT from honest hard working US citizens in order to underwrite international communism and the fluoridization of our water.
  
  * leaves on tinfoil hat just in case *
  
  --
  To have a right to do a thing is not at all the same as to be right in doing it
Re:Rocks by Anonymous Coward · 2012-09-27 11:25 · Score: 0

These meatbags you speak of would have done the job of Spirit and Opportunity in two weeks rather than several years.
Re:Rocks by Tarlus · 2012-09-27 11:27 · Score: 1

Those future houses and vineyards on Mars are totally set. =)

--
/* No Comment */
Look closely by kurt555gs · 2012-09-27 11:29 · Score: 5, Insightful

I see Thoat tracks.

--
* Carthago Delenda Est *
1. Re:Look closely by Velex · 2012-09-27 11:38 · Score: 0
  
  Arg! I wasted all my mod points yesterday! Will somebody else do the honors?
  
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  Join the Slashcott! Stay away entirely Feb 10 thru Feb 17! Close all tabs to prevent autorefresh!
2. Re:Look closely by gslj · 2012-09-27 14:56 · Score: 1
  
  I see Thoat tracks.
  Willis tracks.
3. Re:Look closely by Anonymous Coward · 2012-09-28 03:11 · Score: 0
  
  Haven't we already found footprints on Mars as seen in this guys video? Looks like martians wear Nikes and Reeboks.
4. Re:Look closely by RockDoctor · 2012-09-28 09:38 · Score: 1
  
  I see Thoat tracks. -- * Carthago Delenda Est *
  
  Speaking as a Martian, what have you got against Carthage?
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Re:Rocks by ColdWetDog · 2012-09-27 11:32 · Score: 1

Meat Popsicles!!

--
Faster! Faster! Faster would be better!
Re:Rocks by z0idberg · 2012-09-27 11:43 · Score: 3, Insightful

And imagine how much more they could get done while they sit around on that red rock waiting to die.
Observation by Anonymous Coward · 2012-09-27 12:03 · Score: 1

I'm probably way off, but if Earth's core cooled and solidified, wouldn't a majority of our oceans seep below the crust? It seems like magma prevents water from doing this now because it would turn it to steam. Maybe this is what happened with Mars. Both planets are similar in composition, but since Mars is farther from the sun and smaller, Maybe it just cooled quicker and got a head start in the process. That would mean there's a lot more water on Mars than we can observe. We should drill deep into Mars and find out. Life would probably be hanging on down there too
1. Re:Observation by RockDoctor · 2012-09-28 10:03 · Score: 1
  
  Why would the oceans seep into the crust? Are you implying that there is significant porosity (holes in the rock) and permeability (connections between holes in the rock, allowing fluids to move) in all the rock types comprising the crust? Further, are you implying that that porosity is currently filled with fluid of lower density than (sea-)water - 1030 kg/m^3 ?
  You're wrong on all 3 points.Only a few percent by volume of rocks have more than a percent or so of porosity ; anything with less than a percent of porosity has very low permeability ; most porosity is filled with salty water (density 1015 to 1050 kg/m^3).
  In my industry, we search assiduously for those few rocks with porosity, permeability and a low-density (800 kg/m^3 and lower) pore-filling fluid. We call it "oil" or "gas" ; you may have heard of the industry and it's products.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Re:Rocks by MightyMartian · 2012-09-27 12:04 · Score: 1

Indeed... Like his navel

--
The world's burning. Moped Jesus spotted on I50. Details at 11.
Re:Rocks by Tablizer · 2012-09-27 12:07 · Score: 1

So we spend billions to look at dirt !!
That's no dirt, that's humanity's great great great great great great great great etc. etc. grandfather.

--
Table-ized A.I.
Re:Rocks by Anonymous Coward · 2012-09-27 12:13 · Score: 0

It sure beats sending 2-3 meatbags
I believe those meatbags are commonly referred to as: "Ugly bags of mostly water"
HK-47 would most certainly disagree with your assessment.
What would be really cool by AndyKron · 2012-09-27 12:14 · Score: 1

What would be really cool is if Curiosity found some arrows heads along the banks.
1. Re:What would be really cool by tehcyder · 2012-09-28 02:45 · Score: 1
  
  What would be really cool is if Curiosity found some arrows heads along the banks.
  Well, yes. Cooler still if they found some pony hoof prints. In pink. And a unicorn's teardops solidified into purest diamond....
  
  Sorry, it's Friday afternoon at work. The beer is calling.
  
  --
  To have a right to do a thing is not at all the same as to be right in doing it
Re:Rocks by tom17 · 2012-09-27 12:20 · Score: 1

But foundations still slide off their houses.. or something :)
http://www.bbc.co.uk/news/uk-england-tyne-19725952
Re:Rocks by Caerdwyn · 2012-09-27 12:24 · Score: 1

I believe those meatbags are commonly referred to as: "Ugly bags of mostly water"
As long as you don't ask about the glowy bits. Or the probe code.

--
Everybody gets what the majority deserves.
Props to submitter and editor by elistan · 2012-09-27 12:32 · Score: 5, Insightful

Nice job, submitting and subsequently accepting, an article with a link to the NASA article instead of some random blog linking to a multipage ad-heavy website that only vaguely discusses the NASA article. More of this, please.
1. Re:Props to submitter and editor by sighted · 2012-09-27 14:36 · Score: 4, Interesting
  
  So glad you found it useful, and thank you for saying so. If, however - just for the sake of familiarity - people still want a link to some random guy's website, here's my latest space-related project: http://www.ridingwithrobots.org/earth Except it still doesn't have ads. Oh well, what can you do?
  
  --
  Saddle up: Riding with Robots
2. Re:Props to submitter and editor by bronney · 2012-09-27 16:04 · Score: 2
  
  What an awesome website bro. More of these please!!!
Re:Rocks by Anonymous Coward · 2012-09-27 13:43 · Score: 0

They're made out of meat
You know what the Curiosity rover CAN'T find? by elrous0 · 2012-09-27 13:54 · Score: 0

Love.

--
SJW: Someone who has run out of real oppression, and has to fake it.
1. Re:You know what the Curiosity rover CAN'T find? by bronney · 2012-09-27 16:15 · Score: 1
  
  you sure bro? cause I absolutely love "it".
2. Re:You know what the Curiosity rover CAN'T find? by mcgrew · 2012-09-28 07:00 · Score: 1
  
  There's lots of love for Curiosity... but it won't be found on Mars, it's all here millions of miles away.
  
  --
  Free Martian Whores!
vanity fair (no capitals) by ntropia · 2012-09-27 14:49 · Score: 0

It is amazing how few respected armchair scientists can keep at bay legions of puny exogeologists and so-called experts.
Guess again.... by die+standing · 2012-09-27 14:56 · Score: 1

It wasn't the Egyptians, Chinese, Africans, and several South American civilizations, nuh uh, no way. What we have here is clearly an ancient martian craft brewery. This particular area must have been where they made their darker ambers and pales by allowing the beer to flow along the natural terrain to give them those distinct natural martian flavors and colors.
Honest question by jomama717 · 2012-09-27 15:42 · Score: 2

How naive am I to get excited at the thought we might happen upon a fossil?

--
while [ 1 ]; do echo -n -e "\xe2\x95\xb$((($RANDOM&1)+1))"; done
1. Re:Honest question by rs79 · 2012-09-27 16:28 · Score: 1
  
  Very.
  
  --
  Need Mercedes parts ?
2. Re:Honest question by DigiShaman · 2012-09-27 18:26 · Score: 2
  
  Well, if they find some seashells that pretty much answers that question. Anything conical or based on the golden ratio would mean that life is highly likely to be ubiquitous on planets that are wet with water and have a proper climate. Again, that's a big fat IF.
  I still have high hopes that something fossilized might be found (bacteria would still be fantastic). My gut feeling is that planet is too big to be completely sterile throughout its existence.
  
  --
  Life is not for the lazy.
3. Re:Honest question by Alioth · 2012-09-27 22:07 · Score: 1
  
  If they find anything, it's likely to be unicellular. Multicellular life on Earth took billions of years to appear, and we think surface water on Mars disappeared an awful long time ago - probably not giving time for anything more complex than bacteria to appear.
  
  --
  Oolite: Elite-like game. For Mac, Linux and Windows
4. Re:Honest question by Anonymous Coward · 2012-09-27 23:16 · Score: 1
  
  Yes. And the rover isn't equipped to see those. It would require sample return to spot them. However, on Earth there are macroscopic structures that are found commonly in rocks billions of years old (going back about 3.5 billion in the Precambrian), that are produced by communities of microorganisms growing at the surface in lakes and the ocean, mostly bacteria and algae. The structures are called stromatolites. The best-known examples are in Shark Bay, Australia.
  If the rover saw those it in the sediments of Gale Crater it would be .... spectacular. Although there would be a lot of argument about whether they were biogenic or non-biogenic structures, because sometimes you can produce stromatolite-like structures through other processes, and even some fossil occurrences on Earth have been debated for that reason. It would still be pretty amazing, and with the right sort of exposure, you could still make a pretty strong case one way or the other.
  The sediments where the rover is currently driving aren't likely to contain stromatolites. The sediments are coarse sandstones and conglomerates, thought to be deposited on the alluvial fan that forms the plain Curiosity landed on. If you're going to find stromatolites it would be in fine-grained lake deposits, the kind of deposits that people suspect are on Mount Sharp in the middle of the crater, and which are the main target for Curiosity to reach in a few months.
5. Re:Honest question by tehcyder · 2012-09-28 02:39 · Score: 1
  
  How naive am I to get excited at the thought we might happen upon a fossil?
  Not quite as naive as getting excited at the thought that we might find some live red-skinned Princesses of Mars or green six-limbed Warriors of Mars, but not far off.
  
  --
  To have a right to do a thing is not at all the same as to be right in doing it
6. Re:Honest question by RockDoctor · 2012-09-28 10:07 · Score: 1
  
  Not very naive to get excited at the thought. I'm excited at the thought too!
  But I reluctantly have to say that the probability of seeing one is not high.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
7. Re:Honest question by RockDoctor · 2012-09-28 10:10 · Score: 1
  
  Depressingly true.
  I think I'll fire up my Cobra and make another attempt a finding a Thargoid fleet. (An Oolite reference for those benighted souls who don't know the game.)
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
8. Re:Honest question by RockDoctor · 2012-09-28 10:16 · Score: 1
  
  I was stromatolite-fossil collecting a few weeks ago in the Scottish Highlands ; the fossils are fairly subtle, but once you "get your eye in", reasonably obvious.
  But the good news is that these stromatolites appear to have been deposited (a billion years ago) in intermittent or ephemeral lakes in an inter-montane basin, interbedded on a large scale with coarse sands and conglomerates.
  Which (the conglomerates) is what we're seeing here.
  Saw a meteorite's suevite deposit too. Good weekend, well worth the effort.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
fossils by Anonymous Coward · 2012-09-27 16:48 · Score: 1

Time to look for fossils?
Video of the press conference by Anonymous Coward · 2012-09-27 17:17 · Score: 1

http://www.ustream.tv/recorded/25748116
Tell me when they get to sandybridge. by PDX · 2012-09-27 19:32 · Score: 1

If they find divots in smooth river rock it could indicate a metabolic process tore into a rock.
1. Re:Tell me when they get to sandybridge. by kaatochacha · 2012-09-28 04:47 · Score: 1
  
  or golf. Golf on mars.
2. Re:Tell me when they get to sandybridge. by RockDoctor · 2012-09-28 10:21 · Score: 1
  
  If you follow Ian Parson's work ... that's a real possibility. Low likelihood, but not zero.
  But the divots (a good golfing word ; Ian would like it!) are microscopic. Finely microscopic. He uses an electron microscope routinely. (Well, he did before he retired.)
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Wikipedia disagrees a bit by SmallFurryCreature · 2012-09-27 19:54 · Score: 2

Soil is a natural body consisting of layers (soil horizons) that are primarily composed of minerals which differ from their parent materials in their texture, structure, consistency, colour, chemical, biological and other characteristics. It is the unconsolidated or loose covering of fine rock particles that covers the surface of the earth.[1] Soil is the end product of the influence of the climate (temperature, precipitation), relief (slope), organisms (flora and fauna), parent materials (original minerals), temperature, and time. In engineering, soil is referred to as regolith, or loose rock material. Strictly speaking, soil is the depth of regolith that influences and has been influenced by plant roots and may range in depth from centimetres to many metres.
So it doesn't have to contain organics, just has to have been affected by plant roots. Soil is almost always reffered to when talking about stuff to grow things on/in and then on land. You don't talk about the sands of the Sahara as soil after all. Or the soil at the bottom of the sea.
But hey, go right ahead kid, show yourself to be a true dweed and insist on using words by their most strict interpretation, it will warn everyone that you are someone who hasn't any social skills whatsoever. I would warn you to now go try to order soil to fill your kids sandbox but I think it is safe to assume you never will be in that situation.

--

MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
1. Re:Wikipedia disagrees a bit by mosb1000 · 2012-09-27 20:22 · Score: 1
  
  But hey, go right ahead kid, show yourself to be a true dweed and insist on using words by their most strict interpretation, it will warn everyone that you are someone who hasn't any social skills whatsoever. I would warn you to now go try to order soil to fill your kids sandbox but I think it is safe to assume you never will be in that situation.
  Doctor, heal thy self.
  The saying I posted is just a funny way of saying "hey, this stuff (the dirt) is important."
  I wasn't trying to be pedantic. I used to work at an environmental engineering company, and I noticed that the geologists and environmental scientists didn't like it when I referred to soil samples as dirt. One once said to me "I didn't spend 6 years in college to study dirt." I looked it up and it turns out they were right. These nasa scientists aren't studying dirt. Saying that implies what they're doing is less important than it actually is. Even if it's not on mars, the soil covering the earth is very important to us, and many people make studying it their live's work.
2. Re:Wikipedia disagrees a bit by kaatochacha · 2012-09-28 04:37 · Score: 1
  
  This discussion has me so confused, I believe I just soiled my pants.
What NASA is hiding from us by SmallFurryCreature · 2012-09-27 19:55 · Score: 1

You have to search through all the photographs, they try to hide them in the flood of images, but one some pictures I can clearly see the tracks of a wheeled vehicle. PROOF there are aliens!

--

MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
1. Re:What NASA is hiding from us by mcgrew · 2012-09-28 07:22 · Score: 1
  
  Of course there are aliens on Mars. Three of them, although one has died. And all three have wheels. Plus, there are a couple of aliens in orbit around Mars.
  
  --
  Free Martian Whores!
2. Re:What NASA is hiding from us by RockDoctor · 2012-09-28 09:42 · Score: 1
  
  [Counts] Seven, at least, though not all have wheels, and the majority are immobile and unresponsive, (and possibly fragmentary)
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
They're just saying this to piss of the Fundies by WOOFYGOOFY · 2012-09-27 23:03 · Score: 1, Troll

This is a perfect example why doing science is morally wrong.
Aw nuts by opentunings · 2012-09-28 00:05 · Score: 1

Now when I go to Mapquest and type in "Hottah" they're going to prompt me "Earth or Mars?"
1. Re:Aw nuts by rwise2112 · 2012-09-28 04:16 · Score: 1
  
  Now when I go to Mapquest and type in "Hottah" they're going to prompt me "Earth or Mars?"
  Try Apple Maps. It'll automatically go to Mars.
  
  --
  
  "For every expert, there is an equal and opposite expert"
Re:Rocks by khallow · 2012-09-28 03:00 · Score: 1

We all are waiting to die. Doing a lot of constructive stuff (like say, science research on Mars many orders of magnitude faster than anything we're used to today) while you wait, seems a better use of your time.
Dammit... by Anonymous Coward · 2012-09-28 03:31 · Score: 0

They need to stop exploring mars and put some of those billions into warp drive functionality. I WANT TO MEET GREEN ALIEN WOMEN!!!
Almost looks like a slab of concrete by Stan92057 · 2012-09-28 04:04 · Score: 1

Almost looks like a slab of concrete.

--
Jack of all trades,master of none
Re:Rocks by Anonymous Coward · 2012-09-28 05:38 · Score: 0

Yep, because all manned Mars mission plans are one way suicide missions...
Er... why water? by DarthVain · 2012-09-28 06:50 · Score: 1

Doesn't "round" stones predicting water, just mean they thing it round becase it was caused by erosion caused by water?
What is to stop other kinds of erosion from also making round stones? Would not wind erosion given enough time perhaps do the same thing? Do they not have terrible dust storms on Mars? How are they measuing how long it took to create the erosion?
Anyway it seems a bit of a leap to me.
1. Re:Er... why water? by RockDoctor · 2012-09-28 10:24 · Score: 1
  
  Read the posting I made earlier including the word "ventifact." There are not likely to be many other people using that word here.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Re:Rocks by mcgrew · 2012-09-28 07:43 · Score: 1

I see you've never seen Surrogates. Pretty good SF flick, you should check it out.

--
Free Martian Whores!
Re:Rocks by RockDoctor · 2012-09-28 09:31 · Score: 1

Yes.
You have a problem with that? (Hint : look at the username.)

--
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"