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"Puddles" of Water Sighted on Mars

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.'"

14 of 237 comments (clear)

  1. Well, admittedly, the image is interesting... by Icarus1919 · · Score: 5, Informative

    Direct link to image: http://space.newscientist.com/data/images/ns/cms/d n12026/dn12026-2_250.jpg

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

    1. Re:Well, admittedly, the image is interesting... by CorSci81 · · Score: 4, Interesting

      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.

    2. Re:Well, admittedly, the image is interesting... by MichaelKaiserProScri · · Score: 5, Informative

      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.

  2. That's nothing by Kohath · · Score: 5, Funny

    We have puddles of water right here.

    1. Re:That's nothing by naoursla · · Score: 4, Funny

      Whoa! How did you get on Mars, dude?

  3. Re:WTF? by armando_wall · · Score: 5, Funny

    "They made it about a whole 2% larger. I feel ripped off by shit like that on the web."

    Are we still talking about images here?

  4. JPL's original pictures by mrcgran · · Score: 5, Informative

    It seems that the colored composite picture shown in newscientist's article was derived from these two original left-right pictures from Opportunity's navigation cameras on day 285. There are many more similar pictures around day 285, with these flat paths around the flat stones. In the 'Burns Cliff' Color Panorama (high res), 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, 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)

  5. not flat, part of Burns Cliff by J05H · · Score: 4, Informative

    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

    This "puddle" however, doesn't stand the test.

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  6. Re:Why oceans are blue by Anonymous Coward · · Score: 5, Informative

    That is an urban myth. The oceans are blue because pure water is very slightly blue. 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.

  7. Not this again by orangepeel · · Score: 5, Informative

    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 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.

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  8. cant be water by Jarik+C-Bol · · Score: 4, Insightful

    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.

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  9. Re:Why oceans are blue by Dunbal · · Score: 4, Interesting

    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.

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  10. Hats off to NASA, this time by moranar · · Score: 4, Insightful

    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.

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