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Mounting Evidence for Water on Mars
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."
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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 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!
but it also has Hydrogen Peroxide in the atmosphere!
link
Antiseptic and life-killing, the chemical helps explain why the martian atmosphere and surface are void of life.
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From the little I remember from geology, wind blown (aeolian) sand grains are more likely to be angular, while grains move by water are rounded. This is one indicator used to distinguish the provenance of a sedimentary rock at outcrop.
Yeah but it doesn't matter if there is water or not because if the supposed "Life Killing Chemical" is really present in the martian atmosphere like this article says it is...
3 82 7.asp
http://www.sltrib.com/2004/Mar/03012004/utah/14
Keep the faith, share the code
How about the viking landers in '76?
They had a little scoop so they could get some soil and perform tests for life.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
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 0 5/29_dust.html
http://www.spacedaily.com/news/mars-atmosphere-01
and the second trip at:
http://www.berkeley.edu/news/media/releases/2002/
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.
Aye, but the scale is different. These spherules are said to be approximately the size of BB's. This causes them to interact with the surrounding terrain in a much different fashion; something as small as a grain has a greater likelihood to get caught by a rock or some other feature of the landscape than something as big as a BB.
Is this truly the only Earth I can live on?
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
A BB is a ball bearing.
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.
Please explain to me how a basically random physical phenomenon operating on rock fragments of variable size & shape will result in the formation of perfectly spherical objects which are all very close to each other in size?
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).
Sorry, but the ESA orbiter showed this more than a month ago. NASA is just too late
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.
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.
BB is actually a reference to the American system of measuring the size of lead/steel shot in shotgun shells. Here is a convenient table. BB shot is about 4.5 mm in diameter.
Mea navis aericumbens anguillis abundat
Might the subsurface "sparkling" spheres be a form of Martian brine shrimp eggs
similar to the Great Salt Lake brine shrimp eggs???
photo 1
photo 2
More on the Great Salt Lake Brine Shrimp ecology can be found here:
Link 1
Link 2
Soil Crust Analogs on Earth???
Likewise a USA Today article Imprint shows Mars craft landed in 'weird stuff' 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. "It has quite alien textures."
Might this soil crust on Mars be same/similar to the biological soil crust found at Arches National Park (Moab, Utah)?
Additional details regarding biological soil crusts maybe are to found here:
intermediate details
advanced details
I believe Juanita
Anyone know where the images of this 'pasta-like' object are?
You can see it here. 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. 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.
Most planetary scientests have accepted for decades that water is a major force in Martian geology. The polar ice caps have long been known to have a substantial water component. The Viking missions detected chemical salts typical of evaporation deposits. Nothing other than water has been proposed for the major outflow channels found all over the Martian surface. See planetary scientist William K. Hartmann's excellent recent book, "A Traveler's Guide to Mars" for lots more information.
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!
And have the rovers confirmed the presence of peroxides? Remember the Viking biologic experiments came back positive. It seemed at the time, like some folks went into overdrive to explain the results on the basis of soil peroxides. That always seemed far-fetched, to me, on a planet covered with FERRIC oxide. The Martian soil crusts sure look like desert crusts on earth, and on earth the crusts are loaded with cyanobacteria. The predominance of CO2 would argue against that, but there is almost NO ATMOSPHERIC NITROGEN. Is there nitrogen (read: ammonia) in the Martian soil? Nitrogen is an essential component of amino acids and proteins.
"...while history is usually explicable it is often irrational" --Roger Spiller