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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.'"
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?
We have puddles of water right here.
Even the Mars rovers are starting to see mirages after 3 years on a desert planet.
-- my sig got
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.
There are two kinds of fool One says 'This is old therefore good' Another says 'This is new therefore better'- Dean Ing
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.
Dedicated Cthulhu Cultist since 4523 BC.
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)
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.
i nds-puddles-on-the-planets-surface.html
http://www.marsroverblog.com/discuss-mars-rover-f
This "puddle" however, doesn't stand the test.
gigantino.tv - Heavy but weighs nothing.
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.
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.
http://www.flickr.com/photo_zoom.gne?id=536615119& size=o
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...
---GEC
I'm but the humble pupil, seeking to snatch the scratchbuilt pebble from the master's fully articulated hand
Am I really the only one here who actually played in the dirt as a kid?
... 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...
...but with that wind erosion, what would be the lowest limit for particle size on the Martian surface?
... 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.
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
without any liquid water...
without any biological activity...
without any volcanic activity...
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
Mars: where a dry surface flows like water.
Whoever designed level 61 in Frozen Bubble is a sadistic bastard.
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.
I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
They're canals!
We've known about the Martian canals for decades!
This is news?
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 of blue. That's UV.
[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 to turn off, as heading into the ocean every night.
PS: Water reflects blue a bit better, but honestly, check some photos. You see the reflection on the surface. Water isn't cartoon bright blue as shown on the "proof photos" on Mars, especially when you lack the blue sky.
Keep in mind that our pools are also laden with chemicals to keep them "clean"
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In nature there aren't too many sources of pure H2O, collections of glacial water pools/collections are probably one of the few naturally-occuring sources of relatively pure water, and you'll note that they tend to be quite blue.
http://crevassezone.org/Photos/Graphics/2836L-(Og
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http://www.marsroverblog.com/dyn/entry/54280/disc
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.
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.
Seven puppies were harmed during the making of this post.
Why do they keep sending such crappy cameras to mars? If I took a picture of a puddle of water with my 1 megapixel cellphone camera I could tell it's a puddle of water. Why is it so hard for them to take good pictures?!
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.
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 definition, created in running water.)
So, while I agree that these pictures don't show liquid water and that we haven't seen any puddles of water on Mars yet, an ultra-dry explanation of Mars doesn't work, and liquid water or salt solutions on the surface of Mars are not just possible, but likely.
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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