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"Puddles" of Water Sighted on Mars

Posted by Zonk on Sat Jun 09, 2007 02:22 PM
from the interstellar-jackpot dept.
eldavojohn writes "Further reinforcing the theory of a wet Mars, NewScientist is reporting on what appear to be water puddles in newly taken images from the Mars rover. While these results are controversial, the assumption that these blue 'puddles' are water still has to be tested by engineers. They'll try to measure the uniform smoothness of the puddle surfaces. Analysis will also examine their apparent 'opaqueness', where in some areas observers claim to see pebbles underneath the surface of the blue areas. From the article: 'No signs of liquid water have been observed directly from cameras on the surface before. Reports last year pointed to the existence of gullies on crater walls where water appears to have flowed in the last few years, as shown in images taken from orbit, but those are short-lived flows, which are thought to have frozen over almost immediately.'"
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[+] Surprising Further Evidence for a Wet Mars 192 comments
Riding with Robots writes "When the robotic geologist Spirit found the latest evidence for a wet Mars, 'You could hear people gasp in astonishment,' said Steve Squyres, the lead scientist for the Mars rovers. 'This is a remarkable discovery. And the fact that we found something this new and different after nearly 1,200 days on Mars makes it even more remarkable. It makes you wonder what else is still out there.' The latest discovery, announced today, adds compelling new evidence for ancient conditions that might have been favorable for life, according to the rover team."
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  • by Icarus1919 (802533) on Saturday June 09 2007, @02:25PM (#19452293)
    Direct link to image: http://space.newscientist.com/data/images/ns/cms/d n12026/dn12026-2_250.jpg [newscientist.com]

    Gotta say, can't think of what it could be besides water. On the other hand, aren't the images artificially colored?
    • Re: (Score:3, Informative)

      Yes they are. And water probably wouldn't look that blue ob the red planet ;)
      • Re: (Score:2, Informative)

        Actually, the pancam isn't completely black-and-white: http://marsrovers.nasa.gov/mission/spacecraft_inst ru_pancam.html [nasa.gov]
        • To be more precise, the CCD in the pancam is black and white, but there are a variety of filter they can place in front of it. When they do a "true" color image they use a red, green, and blue filter and take three exposures. However the pretty "true" color images rarely support the science they are doing, so they may, for instance, shoot a picture in infrared, visable green, and UV because that best suits the science they are doing. Sometimes they arbitrarily assign colors to these frequencies of light and make a false color picture. Other times they take a picture of a color reference target attached to the rover using the same filter set they took the picture with. Since the computers on Earth "know" what colors are on the reference chart they can produce a close approximation of the colors in the scene. They photographed the reference chart with ALL of the available filters in a variety of lighting conditions, so they have a pretty good idea that the colors are reasonably accurate. So it would be useful to know if this picture was color corrected or if it is a false color image.
            • I don't know. One would think that they went as durable as possible since the accuracy of the color reference is critical to getting accurate pictures. But the rovers were only supposed to last about 3 months. I think we're going on 5 years now, so who knows.
      • Here is a picture of it in its original b&w glory from another angle.
        With the rover driving over that area.

        http://marsrovers.jpl.nasa.gov/gallery/all/1/n/285 /1N153484776EFF37MIP0757R0M1.JPG [nasa.gov]

        It does look a lot like track prints in mud.
        • Actually, the Martian sky frequently has a pinkish hue due to the large quantities of suspended dust grains. If you live anywhere that has wildfires (like SoCal) think of what it's like when the air is full of smoke.
        • by Anonymous Coward on Saturday June 09 2007, @03:47PM (#19452795)
          That is an urban myth. The oceans are blue because pure water is very slightly blue [lsbu.ac.uk]. In large quantities, like lakes or oceans, the blue comes out. If it was just due to the reflection of the sky then large bodies of water would by white on overcast days.
          • This is consistent with the picture. Depending on the filter they took the picture with, it might look VERY blue. They commonly represent the image obtained from the UV filter as "blue" when they want to produce a color image from the pancam, but have not used the true blue filter in the image set. Give the absorption spectrum, that would make it look bluer than usual because water absorbs UV even better than blue. Notice that the lowest point of that graph is just outside the visible range to the left
            • Re: (Score:3, Insightful)

              [snip].... water is very slightly blue, in large quantities, the blue comes out .... [/snip]

              This is true. Glass is also slightly green.


              I attest to that. And air is slightly cyan/blue as well. In large quantities (such as a big sky), the cyan/blue comes out.

              There's nothing like reading a good piece of science on Slashdot.

              There's something I can't figure out: for some reason on sunset and sunrise, water becomes slightly yellow/red, just like the air.

              I'm not sure what's with that, maybe as the sun gets ready t
            • by Dunbal (464142) on Saturday June 09 2007, @10:37PM (#19455195)
              As a matter of fact, the ocean looks gray on an overcast day. In other words, it's the same color as the sky.

              Protip: any SCUBA diver will tell you that water absorbs the red end of the spectrum much faster than the blue end, which is why you lose all the reds at around 40 feet depth, and at 100 feet everything is mostly shades of blue. It has NOTHING to do with the color of the sky which, because of the Compton effect (ie lots of water vapor in our atmosphere) is also blue.
                • Re: (Score:3, Informative)

                  As for the topic in question. The tracks in the original image do indeed look like they have gone through a puddle. How it could survive in the near vacuum is interesting ... maybe it is very salty

                  The triple point of water is at 0.01 C and 0.006 atm, which tells you that plain water can, in fact, exist in liquid for in "near vacuum" (salt, of course, probably helps even more). Those conditions are pretty close to what you get on Mars.
    • Gotta say, can't think of what it could be besides water.

      The smoothness and transparency of the features could suggest either water or very clear ice, Levin says. "The surface is incredibly smooth, and the edges are in a plane and all at the same altitude," he says. "If they were ice or some other material, they'd show wear and tear over the surface, there would be rubble or sand or something."
      Karma whoring? Check

      Didn't RTFA? Check

      • Karma is so easy. Why whore it? No one would whore around for pennies? Air? I think I might write a script that will try to gain Karma for me. Candidate rules would include:

        1) Use proper html to make lists.

        2) Do a google/wikipedia search for the Nouns in TFA and link those into the page.

        3) If its a science article use Google Scholar, and use citations.

        4)Don't post first, but do post near the top, anytime a noun is close to your topic withing a semantic network dog->mammal->cat.

        5) use joke reposi

    • by CorSci81 (1007499) on Saturday June 09 2007, @03:01PM (#19452503) Journal

      Yes, they're colored, and lots of things don't look quite normal under the lighting conditions on Mars. Right off the bat I have a lot of reservations about this work.

      1. His analysis method is based on stereoscopic image reconstructions of a height field. His claim essentially seems that there was no solution everywhere the picture was blue, so it must be flat. Unfortunately, this technique is pretty lousy for extracting height fields. It's noisy, and contrast issues cause it to fail frequently (I know, I've done it myself).

      2. He has no spectral data or any other data to back up his claim. Granted, he's a Lockheed engineer and may not have access. But I have a hard time believing the vast team of scientists analyzing the data overlooked something so obvious.

      3. And finally there's Mr. Levin's history of publishing rather dubious claims regarding water on Mars in the Proceedings of the SPIE but never once a full paper in a peer-reviewed journal that covers planetary science. Not that I want to make a personal attack, but this isn't the first time he's made a dubious claim that was never verified.

      So, while it's intriguing and might be worth a second look, I'm still firmly in the skeptic category on this one.

    • I agree that the images are artificially colored. The liquid looks more like liquid C02 runoff from the underground Katari reactor installed in that region 50,000 years ago by the Zebnor tribe. It should be clear, not bluish in color...
    • Re: (Score:3, Insightful)

      Gotta say, can't think of what it could be besides water. On the other hand, aren't the images artificially colored?

      Shoot, it does look like water, a flowing river even, which reflects the blue sky and clouds on Mars.
      Which it doesn't have.

      Also: "Puddles of Water Sighted on Mars". Damn it, Slashdot! What's wrong with that article title? Tell me.

      You forgot the damn question mark is what it is! How many times do I have to repeat: when posting dubious speculative claims that are most likely false, never forget
  • by Kohath (38547) on Saturday June 09 2007, @02:36PM (#19452361)
    We have puddles of water right here.
  • Even the Mars rovers are starting to see mirages after 3 years on a desert planet.
  • Can't be (Score:3, Insightful)

    by Jarjarthejedi (996957) <bookreader13.cox@net> on Saturday June 09 2007, @02:43PM (#19452399) Journal
    Isn't the Mars Rover in an area where there couldn't be free flowing water? Last I checked the temperature and pressure were far from the conditions needed for liquid water to flow freely on a surface.

    And as someone mentioned earlier the images are artificially colored. It's probably just a mineral deposit or something.
    • Re: (Score:3, Informative)

      If it is water, then perhaps there is something present that has increased the surface tension of the water.
      According to this article [ucalgary.ca]

      Certain inorganic salts (called strong electrolytes) that readily dissolve and completely dissociate into their separate ions in water can raise the surface tension by modest amounts. For example a 10.5 mass percent solution of sodium chloride in water will have a surface tension that is raised by about 3.3 mN/m from the pure water level (at room temperature). That is, the sur
  • WTF? (Score:3, Funny)

    by east coast (590680) on Saturday June 09 2007, @02:43PM (#19452401)
    Why did the image in the article have an enlarge feature? They made it about a whole 2% larger. I feel ripped off by shit like that on the web.

    In any case, this is an interesting find.
  • Come on you scientist nerds. Keep examining photographs until you find a face -- no, water. That's it, we must find images that match our preconcieved notion of what it'll take to get a bigger budget, more subordinates, etc.
      • Well, sadly, war is often useful, but anyway...

        How about landers on Venus, Mercury, or any of the dozen interesting moons around Jupiter and Saturn? How about trying the Mars Polar Lander again, getting it right this time, so that we can study the frost?

        We might learn quite a bit if we did any of that. But no. We go back to the SAME DAMN PLACE. It's familiar and easy.

        Really, we don't get good science payback from YET ANOTHER toy driving around on the warmer/flatter part of Mars. Exploring is about going to
  • by mrcgran (1002503) on Saturday June 09 2007, @02:54PM (#19452473)

    It seems that the colored composite picture [newscientist.com] shown in newscientist's article [newscientist.com] was derived from these [nasa.gov] two [nasa.gov] original left-right pictures from Opportunity's navigation cameras on day 285 [nasa.gov]. There are many more similar pictures around day 285, with these flat paths around the flat stones. In the 'Burns Cliff' Color Panorama [nasa.gov] (high res) [nasa.gov], the newscientist's image is just a fraction of the cliff: it's in its very center, where you can see a V and the steepness of where it is located.

    1) The surface just seems a bit too steep to me to accumulate any liquid water in such amounts for a pond, since it's facing up the border of the crater in the original pictures. The rover was taking the picture from the bottom up, so also the material wasn't in the lowest part of the terrain.

    2) In the original JPL's pictures, you can see the same 'watery' material all way up to the border of the crater: it's distinctly darker. In the panorama [nasa.gov], it's interesting to note that it doesn't go all the way down to the bottom of the crater, where you can see a brighter dust covering everything.

    Does this darkness means humidity? I fail to see streaming water, maybe flat thin ice sheets from a humid surface but this seems to be explicitely discarded when the author says that "If they were ice or some other material, they'd show wear and tear over the surface, there would be rubble or sand or something." (btw, sand on this steep cliff?) A very thin dark powdery sand looks more likely, but someone needs to go there and poke it to be sure. Any ideas about this? I'm unable to find the original paper to have a look at it.

    Can anyone explain how they came up with the bluish hue in the composite picture, since the original pictures do not seem to have any filter information? (the 25th character in their names is 0 instead of some specific filter frequency [nasa.gov])

    • The original pictures do look like they are on a slope and it does look like sediment in them. Plain water can't stay liquid for very long at Mar's near vacuum. So the question is what water solutions can stay liquid at that temperature and pressure and for how long? Mars is by no means wet. It is mostly dry, but that doesn't mean it's not damp in spots.

      Looking at the very hi-res version of the panorama [nasa.gov] reminds me of damp soil. If it were shallow liquid the shadows would look different in them I think. Th
      • Re: (Score:3, Interesting)

        Plain water can't stay liquid for very long at Mar's near vacuum. So the question is what water solutions can stay liquid at that temperature and pressure and for how long?

        The triple point of water is around 0.01 C and 0.006 atm, which tells you that even plain water can be liquid at surface conditions that can exist on Mars. Salt solutions can exist in liquid form over a much wider range of conditions.

        See also here:

        http://mars.spherix.com/spie2/spie98.htm [spherix.com]
      • Re: (Score:2, Informative)

        I meant to add: There are more shots of the same scene on the Sol 279 [nasa.gov] page. These are from a different angle, and if you cook up a way to view stereoscopic pairs ( I used MS Paint ) you can see that the "water" surfaces are far from flat, as well as being inclined, of course. Try this left [nasa.gov] and right [nasa.gov] pair, which shows the top part of Levin's image viewed from the right side. The horizontal blue portion of Levin's "puddle" on the upper right is seen to have significant relief in this pair. You can actually s
  • by J05H (5625) on Saturday June 09 2007, @03:00PM (#19452499) Homepage
    MarsRoverBlog.com is discussing it, this isn't a flat area, but on a 20-30 degree slope. It is part of Burns Cliff in Endurance Crater.There is plenty of evidence for water on Mars, just not in these images. There is evidence of something other than dust, probably water seepage from underground, at Meridiani and Gusev. Orbital images have shown water in the polar caps and probably a frozen sea in Elysium. There are what appear to be ponds and flowing rivers in some images, especially the first Mars Express image released a while ago.

    http://www.marsroverblog.com/discuss-mars-rover-fi nds-puddles-on-the-planets-surface.html [marsroverblog.com]

    This "puddle" however, doesn't stand the test.
  • by bwy (726112) on Saturday June 09 2007, @03:32PM (#19452687)
    The burden of truth typically lies with the person asserting the positive. However, in this case it would be interesting and useful to hear other explanations for this photo, because it *does* appear to reveal something of interest.
  • Does anybody else find it odd that they can't tell whether or not this is water? I mean, were they so positive that they wouldn't find water on Mars that they didn't include any way of testing for it?
  • Not this again (Score:5, Informative)

    by orangepeel (114557) on Saturday June 09 2007, @04:14PM (#19453019)
    Am I really the only one here who actually played in the dirt as a kid?

    Originally an outwash plain during the final ablation phase of a glacier, the 5+ wild acres I grew up on as a kid had a variety of clay, soil, and silt types. This "OMG, there's water on Mars!" reaction has come up at least once before here on Slashdot, after someone posted a link to a photograph that showed dark plumes spilling down a small incline. Some of the reactions here depressed me back then too. Have so many people really become so disconnected from the earth that they can't recognize ultra-fine silt when they see it?

    Ok, so fine ... let's assume you don't have first hand experience with how liquid-like dry silt can be. Just today I read an article on Nasa's site [nasa.gov] that got me thinking about this topic. It's about how one of the rovers has again had its solar panels cleaned off by wind. If Martian winds can pull that trick off, clearly wind erosion must be ongoing on Mars, and has been going on for what, BILLIONS of years? Now...

    without any liquid water...
    without any biological activity...
    without any volcanic activity...

    ...but with that wind erosion, what would be the lowest limit for particle size on the Martian surface?

    Let me put this another way: there has been an erosional force running on that planet for a billion plus years, to this day, and no force (at least on the surface) is present to conglomerate or cement those particles back together. This, to me, means that all surface particles must be being eroded down to some lower limit in silt particle size. I bet there's all kinds of weird and wonderful physics going on down at that level, but I'm digressing.

    Folks, as apparently the only person here on Slashdot who's ever played with dry silt, I have some sad news for you: I would be shocked if there weren't patches around that didn't look a heck of a lot like liquid.

    Here's another story to contemplate: do you remember when one of the Mars rover's got stuck? The NASA engineers went off to the hardware store to recreate the soil conditions, and picked up things like dry cement powder and diatomaceous earth. And you have to remember that Mars' gravity is what, 1/3 that of Earths? Come on kids ... it's nice to dream and all, but what we're dealing with here -- again, at least on the surface -- is one very dry surface that has a heck of a lot of ultra-fine silt lying around in a low gravity environment.

    Mars: where a dry surface flows like water.
    • Re: (Score:3, Interesting)

      Actually I had these same feelings when I first saw the the images of the landing of the NEAR probe on Eros (note the final image [nasa.gov]). There was silt so fine that it flowed like a liquid and even looked like it had surface tension. This reminded me of when I was a kid I had seen fine silt mud settle out in water with a similar effect. Some very interesting physics must be going on the surface of Mars and the asteroids. Particles the size of colloids interacting like molecules to form a quasi liquid?

    • Come on kids ... it's nice to dream and all, but what we're dealing with here -- again, at least on the surface -- is one very dry surface that has a heck of a lot of ultra-fine silt lying around in a low gravity environment.

      It's quite clear that soil surfaces on Mars must regularly be exposed to liquid water. Why? Because we've already pretty much seen it: the Viking lander saw ground frost in its images, and at temperatures and pressures on Mars, that frost can turn liquid.

      (Incidentally, silt was, by de
  • cant be water (Score:4, Insightful)

    by Jarik C-Bol (894741) on Saturday June 09 2007, @04:18PM (#19453043)
    ok, i'm no trained profesional in hydrophysics, but where i'm from, water obeys the laws of gravity. if you look closely at that picture, you see what is claimed to be "water" in a configuration that it could not hold, and/or would not end up in on any surface. especialy a sloped one. (short runs both up and down the "slope" and runs in oposite direction of what apears to be "primary flow" it looks like extermely fine blown sand to me. blown sand on rock.
  • If you look at the colored pic next to the original black and white, it looks like someone was just bored in Gimp and did some coloring. The whole side-hill in the blacknwhite pic must be water if the colored pic is true.

    http://img370.imageshack.us/img370/6572/39317433nj 5.jpg [imageshack.us]
  • by Anonymous Coward
    They're canals!

    We've known about the Martian canals for decades!

    This is news?
  • by Anonymous Coward on Saturday June 09 2007, @08:17PM (#19454535)
  • by Aerovoid (590728) on Saturday June 09 2007, @08:57PM (#19454755)

    There are a number of things wrong with that article.

    1) The images are false colour. All images taken by the rovers (or any probe for that matter) are never true colour. They generally take images through various infra red and green and ultraviolet filters. When combined, they create unnatural coloured images. So that blue soil you see wouldn't really be blue if it were to be seen with the naked eye.

    2) The specific image shown were taken on the rim of Endurance crater, not at the floor of it. Water can't exactly pool on a slope.

    3) Although the summery on slashdot here says "newly taken images...". This is also incorrect. They were taken in 2004.

    I don't doubt that there is water on Mars, but I don't think it can pool on the surface (due to the low atmospheric pressure), nor do I think this photo contains any evidence of pooling water either. It may contain evidence of past water how ever.

    • Re: (Score:3, Informative)

      1) The images are false colour. All images taken by the rovers (or any probe for that matter) are never true colour. They generally take images through various infra red and green and ultraviolet filters. When combined, they create unnatural coloured images. So that blue soil you see wouldn't really be blue if it were to be seen with the naked eye.

      Not exactly true. They can create near-real color images in the same way many digital cameras do. They have seven filters for different wavelengths of light.

  • by moranar (632206) on Sunday June 10 2007, @02:36AM (#19456283) Homepage Journal
    For all the fun we poke at them for mixing imperial and metric units, they've done a fantastic job with the Rover, still working so long after its "due date". Congratulations to all people involved.
    • Drinking Martian water is not something to be done without careful consideration... Martians place a very high value on the sharing of water. If you're going to do it, you mustn't do it without understanding the full implications of doing so - the cultural significance and the implicit promises that accompany water ritual.

      May you never thirst...
    • Re:NASA budget (Score:4, Informative)

      by MobyDisk (75490) on Sunday June 10 2007, @10:11AM (#19458085) Homepage
      The problem is context. I could build a small scale model of my backyard, dig a hole in it, and pour some bleach into it. From the picture, you would think it is a puddle of water. You would base your decision on your decades of experience seeing how things work on this planet. The problem is that Mars doesn't have the same landscape, materials, temperatures, or pressures that earth does. So you can look at the picture and say it looks like water, but it is really bananna pudding, or bleach, or fine nano-particles of dust that ae so light they flow like water. There's a lot of crazy materials in this world, and you can't base a scientific conclusion on Mars from your Earth-based assumptions.