Mounting Evidence for Water on Mars 342
Kent Simon writes "Space.com has an interesting article discussing new evidence from the mars rovers that shows there may really be Water on Mars."
UNIX is hot. It's more than hot. It's steaming. It's quicksilver lightning with a laserbeam kicker. -- Michael Jay Tucker
What's so great about water!? (Score:5, Informative)
OK we all know that water is needed to sustain life on earth, which is why its such a biggie when the possibility of water on extra-terrestial terrains arises.
But what is it exactly about water that makes it so important? Here [uni.edu] is a page which shows some of the most important properties of water. It shows, for example, how capillary action works, a property that allows plants up to 20 feet (i think!) tall to absorb water without using any energy whatsoever!
Hmmm... (Score:2, Informative)
Little mars space men, here we come!
It may have water (Score:5, Informative)
link [sltrib.com]
Antiseptic and life-killing, the chemical helps explain why the martian atmosphere and surface are void of life.
Re:The spherules (Score:5, Informative)
Re:What's so great about water!? (Score:5, Informative)
btw, capillary action is not a unique property of water, it will occur with any liquid that an affinity for the substrate
Moot Point (Score:4, Informative)
http://www.sltrib.com/2004/Mar/03012004/utah/14
Re:Tell news (Score:5, Informative)
They had a little scoop so they could get some soil and perform tests for life.
Re:What's so great about water!? (Score:5, Informative)
The most important action that allows water to go up in those big trees is negative pressure at the leaves, created by the evaporation of water. Take a look here [rcn.com].
Re:The spherules (Score:5, Informative)
There have been at least two expeditions to the Arizona desert by NASA people to study dust devils, both run out of the University of Arizona. I had the opportunity to spend a month in the Arizona desert gathering data on the second trip.
I wouldn't say that NASA is particularly concerned about dust devils -- due to the lower gravity, dust devils on mars would be much weaker than those on earth, even if they are larger. Even on earth, dust devils post little threat. Some of the ones we studied were over 2 miles tall, and you could walk right through them with absolutely no danger. While the original trip was sponsored by the HEDS (Human Exploration and Developement of Space) funded Matador experiment to see if the dust devils posed any danger to human exploration, the primary concerns were over static electricity and dust getting into space suits.
What NASA is really interested in is how dust affect the geology of the planet. In the absense of water or strong winds, dust devils may in fact be the primary erosive force on Mars. During the first half of the 20th century, astronomers noticed that Mars changed color depending on the season, and this led them to beleive that there was rich vegetation on Mars. When the first orbiters and lander arrived, we learned that this wasn't quite true, but we still had no other solution. Now, scientists believe that is was dust devils, which are a seasonal occurance, that were actually reconfiguring the landscape of the planet. We have actually seen pictures of light colored planes that are crisscrossed by dark dust devil trails.
The problem is that very little is known about dust devils on Earth. I only know of one scientific paper published on the subject. While some of the work we did was trying to find out the proerties of dust devils, especially the electrostatic properties, to help create an accurate model for their formation on Mars, this was not really why we were there. The primary goal of the NASA researchers was to study the dust devils on earth in order to learn how to study them on Mars. We were mainly out there to test a set of instruments planned for Matador (including some far out stuff, like using a special UV camera to detect sparks caused by static electricity).
If anyone is interested, there is an article on the first trip at:a .html [spacedaily.com] 0 5/29_dust.html [berkeley.edu]
http://www.spacedaily.com/news/mars-atmosphere-01
and the second trip at:
http://www.berkeley.edu/news/media/releases/2002/
Re:The spherules (Score:5, Informative)
Except the spherules don't look like the sand grains you find in Earth deserts. Those would be rounded (because as you say there is lots of abrasion), but rarely spherical, and they tend to show signs of impact and scratching from their fellow grains. So far the spherules appear to lack these features.
Best wishes,
Mike.
Re:The spherules (Score:5, Informative)
Re:What's so great about water!? (Score:5, Informative)
Where did you get this from?
Geologically speaking, life appeared on Earth almost the instant the Earth became hospitable enough for life, about 3.8 billion years ago (or when the Earth was 700-800 million years old. That was only single-celled life, but life nonetheless. The move to multi-celled life took far longer and didn't occur until about 700 million years ago. That's the giant-leap there. If single-celled life appears so quickly and it took so much longer for multi-celled life, then it gives the impression that single-celled life is very opportunistic while multi-celled life isn't necessarily the next step.
Re:Tell news (Score:5, Informative)
ESA decided to send one orbiter and one lander to mars, NASA decided to play safe and sent out not one but two landers, Spirit and Opportunity. And of course, they have their own orbiter, too.
Orbiter? Try Orbiters -- there are two existing orbiters -- Mars Global Surveyor and Mars Odyssey. The MER missions did not orbit.
But when you look at the actual scientific data produced by both the ESA and the NASA mission, you will see that NASA definitely does the better PR work. But what have they produced so far? A few snapshots and panorama pictures (which are nice, but well...)
You don't really have a clue, do you? First, some of those "snapshots" are from the Pancam, which has a variety of narrow-band filters to allow detailed image analysis. Second, the rovers have been collecting a TON of data from the other main science instruments -- MiniTES, Mossbauer, APXS. While these don't produce pretty pictures (just boring spectragraphs), it's a wealth of scientific information.
and some stone probes. But due to their design, they can't drill down further than maybe a few meters (if even that deep).
"Stone probes"? WTF are you talking about? The rovers can essentially spin a wheel in place to carve out a trench in the soil. That can dig in the ballpark of 6 inches. There's also a RAT tool to grind rocks, which only goes a few milimeters -- that's all you need to get past any dust or weathering.
This isn't a sub-surface exploration mission, so complaining about that is like saying Slashdot sucks because there's not enough advice on cosmetics.
but IMHO, it's not really something special: we've seen pictures from mars before, and we've analyzed probes from mars before.
We've never seen pictures like the microscopic imager is taking. And it's naaive to say that just because a couple of previous missions have takes pictures that there's no value in doing anything similar again... For simple example, look at how radically different the Opportunity site is from the other missions (Spirit, Pathfinder, Viking I&II).
So, I'm a lot more impressed by the work done by ESA: although they lost their lander (what a pity...), they concentrated not so much on the PR (no "the best crew in the world!" cheering) but more on actual science
That's an insult to everyone in NASA working on the MERs. Have you ever done any real science? It's obvious you don't know anything about the NASA mission, but to make a blanket statement like that about the science just a couple of weeks into the mission is stupid. It can take months to years to develop all the final results.
Let's look at your other ESA claims:
produced detailled 3D maps of parts of mars which has never done before, and where the big geological structures can be analyzed better than ever before.
Uhm, no. NASA has been making maps since the Mariner and Viking missions in the 60's and 70's. More recently, the MGS and Odyssey orbiters have been producing higher-resolution imagery. MGS has even taken pictures of the rovers on the surface (see http://www.msss.com/mer_mission/index.html).
proved the existence of water on the south pole of mars. NASA asserted that they had detected that in 2001 already, but in fact, they didn't, because they didn't have the right equipment. All they were able to detect at that time was hydrogen, which is a possible indicator for water, but definitely not a prove.
It would be more accurate to say "confirmed," no "proved." ESA's PR is in hyper-overdrive here. Previous results from other missions (especially Odyssey's neutron spectrometer) have led to the forgone conclusion that water/ice is present. ESA's results are an "independant cconfirmation," but are hardly a novel or shocking result.
measured the actual temperature on the mars surface (up to +4 degrees Celsius), which is higher than estimated before.
Aga
Re:What is BB ? (Score:3, Informative)
Specifically, when someone says "a BB" in the US, it means a small ball bearing used in a "BB gun", which is an air powered gun that fires BBs.
These BBs are around 2 millimeters wide. So you have your answer.
Re:The spherules (Score:5, Informative)
Answer : it wouldn't
Shouting "but this is Mars, you can't just compare it to Earth" isn't going to help, we're talking physics here, not some kind of mysticism...
It's not because the planet is a little different from Earth (and let's face it : the differences are relatively minor, with gravity, air pressure, temperature and chemical composition actually being very very close to Earth's):
Gravity: 1/3 of Earth
Air Pressure : 1-10% of air pressure in the high mountains (where pebbles form in streams)
Temperature : 150-290K on Mars, 250-300K on Earth (again, high up in the mountains)
Chemical composition : mainly basaltic rocks, lots of those on Earth too...
Mars is actually the planet which is most like Earth in the whole solar system (not Venus, which is only alike in size, but not in environmental properties).
Re:Tell news (Score:5, Informative)
It is obvious that you didn't read the article. The editor's post of the story was a little misleading because we've known about water on Mars for some time.
Having said that, the article states that they think they are actually SEEING liquid water freeze as it's being pressed upward out of the soil by the rover's wheels. That's much different than detecting it with an orbitor. Also, if I'm not mistaken the ESA orbitor suggested that water vapor exists in the atmosphere, not the soil. The missions are complimentary (ESA and NASA have been assisting one another by relaying commands through both of their orbitors and NASA has been trying to actually find Beagle visually using their orbitor). No one is taking credit for anything they haven't done. No need to get defensive.
Do the numbers? Indeed! (Score:5, Informative)
Hmmm, you should have paid attention in your freshman physics class. No such thing as "negative pressure." What you meant to say was "lower relative pressure" and even then you're still wrong. Even if the leaves managed to lower the air pressure above their surface to zero psi, which of course they can't, the highest you can lift water via air pressure differential is 10.3 meters. A water column 10.3 meters high weighs as much as a column of air reaching from sea level to the top of the atmosphere.
If you want to move water to the top of a sequoia, you've got to use some mechanism other than air pressure differentials. In fact, had you carefully read the page you linked to, you would have noticed that transpiration peters out at around 32 feet.
Re:What is BB ? (Score:4, Informative)
Examples on Earth - Brine Shrimp & Soil Crust (Score:4, Informative)
Might the subsurface "sparkling" spheres [nasa.gov] be a form of Martian brine shrimp eggs
similar to the Great Salt Lake brine shrimp eggs???
photo 1 [brineshrimpusa.com]
photo 2 [utah.edu]
More on the Great Salt Lake Brine Shrimp ecology can be found here:
Link 1 [brineshrimpusa.com]
Link 2 [brineshrimpusa.com]
Soil Crust Analogs on Earth???
Likewise a USA Today article Imprint shows Mars craft landed in 'weird stuff' [usatoday.com] describes "The soil was stripped up and folded in an interesting way," said Jim Bell, who designed the panoramic camera that Spirit used to photograph the "mud-like" patch [nasa.gov]. "It has quite alien textures."
Might this soil crust on Mars be same/similar to the biological soil crust found at Arches National Park [nps.gov] (Moab, Utah)?
Additional details regarding biological soil crusts maybe are to found here:
intermediate details [soilcrust.org]
advanced details [soilcrust.org]
Re:Where's the Pasta? (Score:1, Informative)
go to the nasa mars website, and look at All Raw Images. Look at the Opportunity microscopic images for late Feb (sorry, i don't remember the date). There are some shots of el capitan after it was ground by the rat...looking at the center of those pics, enlarge if you can, and you can see a little rotini thing inside one of the little crevices. Not to jump to conclusions, but what the heck...looks like a benthic worm fossilized in its burrow.
Andy
Mars in Color (Score:2, Informative)
http://xpda.com/mars
has combined a lot of the filtered photos into reasonably good color images. I might have to visit Mars to verify the accuracy of the color...
Re:Where's the Pasta? (Score:3, Informative)
You can see it here [nasa.gov]. It's a little above and to the left of the center of the picture.
Other pictures from that day (sol 30 for Opportunity) are here [nasa.gov]. They drilled the area in the following days and there's a picture of the 'pasta' post-drilling, but finding that image is left as an exercise for the reader.
Re:huh? (Score:2, Informative)
"Negative pressure" MUST mean lower relative pressure.
This is why water pumps are placed at the bottom of deep wells. The maximum height a pump can pull water from a lower elevation is 30 odd feet. A pump submersed in a well can send water up as high as it wants, as long as it can produce a high enough pressure.
In other words, 0 psi is as low as you can go, there is no such thing as a pressure with a negative value.
Re:What is this all about? (Score:3, Informative)
Well, actually it means that you're spending more than the next 25 highest spending nations combined - not quite all nations. I've done some debating on the space programs recently and you have to have you statistics right unless you want to get shot down badly.
All told, spending more on defense than your next 25 competitors combined does still seem a little silly - especially considering that the top few of those are britain, france, russia, and other key allies.
Not sure why this is such a big surprise (Score:4, Informative)
Evidence of *recent* water activity is interesting and important, but the loss of this nuance is typical of "news" journalism, which must justify every story as Brand! New! Exciting! Information!
Re:What's so great about water!? (Score:1, Informative)
Re:It may have water (Score:2, Informative)
Acting as a catalyst, it drives the abundance of carbon dioxide and carbon monoxide in the martian atmosphere. Without hydrogen peroxide, molecular oxygen -- now a tiny sliver -- would soar to compose 10 percent of the martian atmosphere.
which sounds like it would make a difference
Water is only one factor (Score:4, Informative)
Re:It may have water (Score:4, Informative)
There was a Wired article (this month's I think) where they detailed a series of scientific missions to the Atacama desert down in S. America. The conditions closely mimic Mars in the extremely low water levels and high UV exposure. The result was that they were unable to find ANY bacterial life in the soil, even when digging several feet down. (although I have some issues with the subsurface results they got) Even an attempt to seed the soil with extremophiles from another desert failed.
It's possible that there might be something buried under the dirt in the Martian soil but even that's pretty chancy. Without a source for energy generation, those bacteria won't be able to repair damage from natural radioactivity in the soil. In our soil there's plenty of organics that bacteria can use for a power source but that carbon ultimately came from solar-driven photosynthesis which the surface conditions rule out.
These are the only possibilities I can think of for Martian life:
1: underground life that is able to sustain at least some basal metabolic rate from a chemical energy source. That energy source would be either organic deposists from an aearlier period of Martian life where photosynthesis was possible or some sort of geological organic chemical formation pathway or hydrogen gas generated from natural radioactivity.
2: Life in geothermally driven water sources or locked into ice. There is a significant amount of life even in the dry plains of Antarctica which indicates that even solid ice is capable of supporting life.
3: some sort of non-standard biological chemistry which is far beyond my ability to speculate about.
Re:huh? (Score:3, Informative)
There IS. The evidence is in the fucking link I provided! Here's another part of the text (highlighting by me):
The rattan vine may climb as high as 150 ft on the trees of the tropical rain forest in northeastern Australia to get its foliage into the sun. When the base of a vine is severed while immersed in a basin of water, water continues to be taken up. A vine less than 1 inch in diameter will "drink" water indefinitely at a rate of up to 12 ml/minute.
If forced to take water from a sealed container, the vine does so without any decrease in rate, even though the resulting vacuum becomes so great that the remaining water begins to boil spontaneously. (The boiling temperature of water decreases as the air pressure over the water decreases, which is why it takes longer to boil an egg in Denver than in New Orleans.)
you can check the Wikipedia [wikipedia.org] too, or if you're not overly lazy google for "Transpiration pull".
Again, if you think the term "negative pressure" is not accurate, say so, but don't try to redefine it if you have no idea what you're talking about. If you get a sealed syringe and pull the plunger, what kind of pressure are you applying to the air sealed inside? Depends on the reference perhaps? This is how the water goes UP in the plants.
Shit, I don't know what's worse, the stubborn refusal to read the text provided or the ignorant mods that keep moding this tripe up.
Some physics guess's (Score:3, Informative)
Ok, Gravity 1/3 rd. (roughly, everything here is roughly and ballpark)
Atmospheric pressure 1/10 th.
So for a given volume the amount of wind speed to push is going to be:
If I remember correctly it's double the wind speed and you quadruple the force. So it's 1/10 the pressure but it can only do 1/40 th the work for a given speed. So if you have a wind on earth that pushes against something with a force of 4 Kg at a speed of 10 Kph then on mars the same 10 Kph wind would only have a force of 62.5 grams, if you double the wind speed to 20 Kph you get 250 grams. Double it again to 40 kph and you get a force of 1.0 Kg and double a last time gets you to 4 kg with a wind speed of 80 Kph. So to get the same force you need 8 times the wind speed.
Of course it's not quite that simple. The 1/3 rd gravity means the same force seems to do more. What it really means is that it takes less force to do anything where gravity is a component. Friction for instance or any operation involving an up or down component.
I would guess that the best ways to simulate it here on earth would be to modify the other parameters to match our gravity. For instance, if your interested in how water might have worked on rock in that gravity then use something that is 3 times the density of water and see how it behaves on rock. Something as simple as a rock tumbling kit filled with an appropriate liquid mixture and compare the results with those produced by water.
To reflect the difference in air you might try to use a fluid to make the rocks have a similar weight as they would on mars then modify the size to match the density of the liquid vs. the Martian atmosphere which has the added benefit of letting you lower the flow speeds to match as well.
Basically it seems that things would happen slower for the most part whenever anything with a gravity component is involved. Flows would be slower, on the other hand inertia is the same so when 2 particles collide you get the same bang for the buck.
I suspect that weathering based on moving water would be similar. I'm not sure if possible changes in elevation would make up for the lesser gravity, I suspect not though.
Atmospheric weathering should be more noticeable. Because of the density you should be able to sort out those rocks that can and can't be moved as opposed to rocks that could have been moved by water but not by air. The differences in weathering on the various sides of these rocks should answer some questions.
Ok enough of this, time to return to my thorazine and play with the pretty bits...
Long John Silvers better be ready to pay up! (Score:3, Informative)
I am now sure that NASA has found fairly conslusive evidence of water on Mars. Not becuase of the article sited in this story, but because NASA is having a press conference to announce "significant findings" [space.com] tomorrow at 2:00 PM EST.
I think it's a pretty safe bet that there is water on Mars. Long John Silvers better be ready to pay up. I want my free shrimp and I want it tomorrow!