Mars Exploration Rovers Update - February 13, 2004



The answer is in Bagnold's "fluid threshold" equation:
Vc = a*sqrt(k*g*D)
Where: Vc = critical wind velocity to lift a particle is then a = empirical constant g = acceleration of gravity D = particle diameter
k = (rhoP - rhoA)/rhoA
rhoP = density of particle rhoA = density of air
A particle might have a density of 2.73 g/cm^3 (rhoP) which would be much greater than rhoA for either Earth or Mars, so k would simplify to approximately rhoP/rhoA. Since Mars has say 1/100th of the density of Earth's air, k will therefore go up on Mars by a factor of 100. On the other hand g is 3 times less than on Earth, so k*g*D only goes up by a factor of 33. The square root of that means that Vc would be 5-6 times greater on Mars than on Earth.
Not quite as bad as one might think.
Joe
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And few obstructions, such as trees.
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outcrop
Earth-like ,

could
appearance
I guess that my point is, that the current stock of water on Mars might suffice for a few climate-extremes to produce wadies and gullies - but not enough to form a free-flowing body of water. The point does not necessarily need a dramatic escape of water out of Mars either.

A hot and welded ash is not obvious and probably lacks other traces of it's being - like the free-flowing water scenario leaves a lot to be desired. But how much of a volcanologist am I?

Something like that. My focus would be on 'what would rain from the sky?'. The first steps in an active hydrosphere is clouds. You know that I have anticipated a lot of dust or clay-size sediment as a consequence of prolonged erosion if a drain for the dust is missing. So basically I see the spheres as the drain. I'm not too much of a meteorologist to know of what to anticipate from the combination of dust and clouds - but I can come up with some speculations. Since we have seen clouds, my idea may not be too far off, and may not necessarily include too dramatic changes from the present situation.
The exposure may be an anomely - related to an extreme climatic situation, like what could have formed the gullies. It is not evenly distributed but this could be induced by both wet or dry dunes - I favour the dry dune for these speculations. The exposure expresses a chemical seggregation .. it does not seem to constitude an average reed 'dust'. I would see such a seggregation possible in the free atmospheric flow of dustparticles (also constituting salts and other evaporites), icecrystals and droplets. This flow could be prolonged in time. And I cannot dismiss the idea that the wet aerial aggregations could evaporate it's watercontents to form perfectly spheric aggregates at the time of hitting the ground.
I think that Curtis provides information that generally enhances the posibillity of 'coalesence' of finegrained particles. The armour of hydroxides that limits chemical weathering on Earth -if attributed to H-bonding to broken bonds - could be exchanged by availability of more H-rich compounds that may become H-bond 'bridges' between particles with positive broken bonds (like the silicates).

If I serve my teachers credit, I would be able to - from the low angle onlap - to express something decent on the depositional environment. Sorry teachers. But I most certainly know what I would be looking for the next time I get around such information. (Thanks for Bagnold's, Joe). As an expression of windblown sediment I could 'see' thin sheets (light density, non-cohesive) pushed around by the wind and falling at rest with a low-angle discordant onlap.
I did it again - pulled an impressive speculation-stunt. Don't be fooled.
Carsten
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it
seems
necessarily
it's
But
Mars has clouds, just not to the extent that it would make a difference.

the
to
with
Since the crater is the only area in the region that we've explored thus far, we don't know the extent of the bedrock.

We don't know that either.

?
wet
Or before.

Yet it cannot be ignored. If there is one thing that has been learned in the exploration of Mars, it is that the Martian wind and its dust storms play a significant role in shaping the landscape of the planet.

Not really. Our dust storms are never globally encompassing, like we see with the Martian storms. Martian dust storms not only often encompass the entire planet, they often last for many months.

low-angle
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I am an interested amateur only, so some of your terminology terms elude me here. But your post is interesting an informative thanks.Regarding your last idea of raindrops maybe from a severe and infrequent storm rather than persistent earth like rainfall ? Although one problem I thought was if it was rainfall it would have to be a warm environment and the current climate is way to cold for a liquid water to fall as rain. Anyways ifthe climate was warm enough and if the nodules are composed of a material that fuses like a fast drying cement one could possibly recreate soemthing similar here in a lab. Is there a gas that liquifies at the present mars temp that could fall as rain to replace the water part of this precipitate theory?
Otherwise in a dry scenario If the nodules are on the surface maybe they were created more recently rather than be sediments from wind action that have since been disturbed. Going back to the explosion idea I suggested before,.. I dont know if there are enough craters to allow the statistical chance of finding these all over Mars and at the lander site but I was thinking a bit more on maybe how they were created, if by an impact crater event. If lets say at impact either water or another gas either present as liquid or solid in the projectile or in the sediment ,were to be instantly heated to extreme high tempratures. The material that the nodules is made of could also mix in that instance with that breif extremely hot gas cloud above the explosion site sort of like a soupy particulate mix of gas and liquid droplets mixed with the nodule element. As it is forced out and away from the site at great speeds by the explosion the mixture is cooled rapidly as it spreads out into the presumabley extreme cold of the martian atmosphere. This would cause the cloud to precipitate out in a sense into droplets , all small , and very rapidly `freeze` into shape in seconds as they are speeding through the extreme sub zero martian atmosphere and then presumably are hard all consistently sized small frozen droplets when they land around the impact site. They then over time `freeze dry` out the liquid water (or whatever liquid it is) in the sun and climate to the present state of a nodule consisting of just the original material which could have initialy pre impact have been a powder or granular material like glass once was sand? One idea would be to look for similar phenomena at old nuclear test sites as in essense I am suggesting they a sandy or powdery medium mixed in with a liquid and as baked `nodules in extreme rapid heating , cooling and speeding `event` through a cold atmosphere to get the small sized droplet shape. Maybe the thinner matian atmospher would aerodynamically produce a rounder projectile rather than the heavier earth atmosphere which would have elongated the droplets .As I mentioned this phenomena may also occur similarly at nuclear test sites. They then erode by wind into the observed sandy mixture Sean
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snip

What conserns Mars, I'm a newbe too

No, CO2 does not have a liquid fase in the surface temperature/pressure range. So any application of the idea would take a climatic anomaly away from the present cold situation.

It's not advisable to do what I did - refere to an instance without a linked picture. Because the spheres are widespread and have what what seem like multiple modes or origins - and it confuses the discussion.
http://marsrovers.jpl.nasa.gov/gallery/press/opportunity/20040209a/1M1295156 92EFF0312P2939M2M1_mi_RobtE_full-B016R1_br.jpg
This is a detail of the outcrop I refer to

I'm a little blank on that

I figure that to be the general expectations

Some seems fragile (atleas to me) others seems to be melted rock - it would be tempting to unite such a diversity in an impact-event.

They are observed in diverse places and seems to me to have been produced in a widespread process and incooperated by different sedimentary processes. There is a lot of parameters on Mars that differs from Earth - and I think that most find it surprisingly confusing to puzzle the consequences together when the desert-surface from a distance afterall looks very Earth-like. I have in another post tried to let meteorological phenomena be responsible, but most of the spheres seems too large (to mention one thing) to give such an idea much credit. Geochemical considerations may very well hide clues - pressure, temperature, constituents and complexity should be sufficient to keep everyone at a distance from even speculating or predicting.
It' a challenging problem.
Carsten
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I've just looked at the Sol 27 panoramics for Opportunity, and it is very clear to me that these are indeed sedimentary rocks. A simple explanation would be that the spheres are the fossils of some simple organism, that upon dying, would drop to the bottom and be buried in the same manner that fossils here on Earth can be trapped in layers of sediment. You can clearly see that the spheres are trapped in the layers, and that they are eroding out. The least hypothesis is that the spheres were deposited in the layers as the layers were forming. They are more durable than the layers themselves, which is easy to see in the weathering images from the microscope. Furthermore, the spheres themselves show some characteristics that are otherwise extremely difficult to explain using standard geological processes. As a long time amateur rockhound, I have seen and collected many specimens, both abiotic and fossils. I could easily understand a sphere with consistent layering throughout, but not many spheres with similar markings such as parallel grooves or chevrons. I have compiled the microscopic images and performed some contrast and image processing to extract features that are otherwise faint or difficult to discern, and there are definitely common features on many of the spheres. In my (perhaps flawed but experienced) opinion, we are seeing fossils. There, it's been said. I have a good reason to take this position- in 1992, I wrote an article about the possibility of life on Mars (which was published in Astrolog magazine), and used some of the reasoning of Thomas Gold about petroleum formation and organisms that metabolize petroleum. In it, I predicted that organisms could still be extant in the rock of Mars if it consumed petroleum as many such organisms here on Earth do. Also, I predicted that in that case, we should look for fine grained magnetite, which is a metabolic byproduct of the digestion process of those sorts of organisms. This was four years before the flap about ALH84001 (1996) so in a sense I beat them to press with at least two good predictions that matched what they found. At this point, I am very encouraged by what we are seeing that life did indeed exist on Mars, and that if we were to bore deeply into the rocks where petroleum might exist, we would discover that deep inside the planet, there are still organisms that are alive and well. After all, a loss of atmosphere here on Earth would not destroy those organisms that live within the rock. I intend to post these processed images on my website shortly, as this is a very interesting development and it is good, reasonable support for this idea. Once again, I am not a geologist, but I am a scientist and have been a rock collector for about 40 years. My opinions could be completely wrong, but I believe that Opportunity has succeeded in finding remnants of extinct Martian organisms.
Cheers!
Chip Shults
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I now have proof that these spherules are fossils very similar to tiny crustaceans, similar to tadpole shrimp or trilobites. I have a paper in submission for publication documenting the method I used for locating the data. These are absolutely fossils, no doubt about it.
Cheers!
Chip Shults
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February 25, 2004
"Sir Charles W. Shults III" wrote:

Feel free to share those methods with US on the usenet.

Proof is mathematical, science is demonstrative.
Besides, Jonathan has already clearly identified the spherules as the gemmules of a microbial sponge colony : 'porifera jonathanii'.
Nice try, though. Keep up the good work!
Thomas Lee Elifritz http://elifritz.members.atlantic.net
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Has a ring to it~
If this pic doesn't show imprints of skeletal spicules, I don't know what else can!
http://marsrovers.jpl.nasa.gov/gallery/all/1/m/030/1M130846496EFF0454P2933M2M1.HTML
Jonathan
s

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tiny
in
the
gemmules
else can!

http://marsrovers.jpl.nasa.gov/gallery/all/1/m/030/1M130846496EFF0454P2933M2M1.HTML
You are absolutely correct, Jonathan. You don't know! In fact, you don't have a clue.
However, I do, and that is not it. This is:
http://www.palaeos.com/Invertebrates/Porifera/Hexactinellida.htm
http://www.lakeneosho.org/Miss31.html
http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artaug98/spiccy.html
http://www.pbs.org/kcet/shapeoflife/animals/porifera4.html
http://virtual.yosemite.cc.ca.us/randerson/Marine%20Invertebrates/porifera.htm
Oh, by the way, Jonathan? You're a dork.
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February 26, 2004

http://marsrovers.jpl.nasa.gov/gallery/all/1/m/030/1M130846496EFF0454P2933M2M1.HTML
Jonathan, if you want an entire phyla named after you, then you have to do a little more research. Sponges may be soft and spicule free, and although they can get quite large, what you are seeing do not appear to be spicules. Start here :
http://www.cox-internet.com/coop/porifera.html
http://darter.ocps.net/classroom/klenk/Sponge.htm
http://tolweb.org/tree?group=Porifera&contgroup=Animals
Organisms have to work with what they have, and there is little evidence for a lot of free carbon and silicon. What they do have is a lot of sulfur and iron and salts, and a limited amount of phosphorus and nitrogen which would have been grabbed up by the biosphere. If these were indeed porifera, they would most likely be soft tissue colonies of evolved extremophiles and cyanobacteria, basically feeding on themselves and exploiting biomineralization for reproduction.
Thomas Lee Elifritz http://elifritz.members.atlantic.net
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wrote in message :

gemmules of a microbial sponge colony : 'porifera jonathanii'.

can!
http://marsrovers.jpl.nasa.gov/gallery/all/1/m/030/1M130846496EFF0454P2933M2M1.HTML
According the reading I've been doing, spicules are unique to each species. If you look at the original photo that shows gemmules quite like the spheres, you'll see the skeletal spicules are long and curved and tend to hook at the end. Look at the one just above the word gemmule in the left photo below. There are numerous long spicules in the soft tissue.
http://waynesword.palomar.edu/plfeb96.htm#gemmules
Then compare that long spicule with the earlier photo of the thread below imaged earlier. http://www.earthfiles.com/news/news.cfm?IDf2&category=Science http://marsrovers.jpl.nasa.gov/gallery/all/1/m/019/1M129869847EFF0338P2953M2M1.HTML
If the soft tissue has dried up I would expect the long curved siliceous spicules to leave marks just as imaged in the first link above. In that pic, you can see two large brown patches in the upper left corner. Just below them is a small brown spot, just to the left of the small spot you can see a very small thread sticking out and casting a shadow.
But of course these images are open to interpretation, I'm not going to claim I'm correct about everything I say when it comes to non mathematical subjects.
http://www.earthfiles.com/news/news.cfm?IDf2&category=Science http://marsrovers.jpl.nasa.gov/gallery/all/1/m/019/1M129869847EFF0338P2953M2M1.HTML
I never claimed to be an 'ologist' of any sort. Yet I suggested the dunes need to be reconsidered as possible water features, and finally Nasa is beginniing to take another look at them.
Nasa is today calling them geologic ripples instead. They seem to think they're wind blown, but a little common sense is needed here. Wind blown ripples are from gentler winds, yet the ripples are almost exclusively made up of the larger 'pebbles'...spheres. I can only conclude their science team is made up of only geologists that are determined to find non-living explanations for everything. I'm not at all surprised they're still scratching their heads over the spheres and dunes. They're going to contrive wind patterns to explain them both it seems. Good luck!
"This false-color image from the Mars Exploration Rover Spirit's panoramic camera shows peak-like formations on the martian terrain at Gusev Crater. Scientists have been analyzing these formations, which have coarse particles accumulating on their tops, or crests. This characteristic classifies them as ripples instead of dunes, which have a more uniform distribution of particle sizes. Scientists are looking further into such formations, which can give insight to the wind direction and velocity on Mars, as well as the material that is being moved by the wind. This image was taken on the 40th martian day, or sol, of Spirit's mission." http://www.jpl.nasa.gov/mer2004/rover-images/feb-26-2004/captions/image-6.html
I can't wait until Spirit makes it to the crater. Not knowing a thing about that crater I will offer some wild speculation. The bottom of that crater will look like the Opportunity crater. Lots of spheres and more dark clumpy soil, wanna bet? If the crater is big enough there should be 'ripples' too.
Funny how the wind blown 'ripples' are at the bottom of these Gusev craters, I guess there's some odd wind patterns there too. I'm beginning to lose respect for the Nasa science team.
http://marsoweb.nas.nasa.gov/landingsites/mer2003/mocs/Images/E03-00012/E03-00012_05.html
Jonathan
s

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wrote in message :

the > >

what else

http://marsrovers.jpl.nasa.gov/gallery/all/1/m/030/1M130846496EFF0454P2933M2M1.HTML
Linda How is a baffoon. NASA has stated that the landing released a lot of debris from the lander, and are embarrassed by it because they tried to take as many precautions as possible pr prevent it.

http://marsrovers.jpl.nasa.gov/gallery/all/1/m/019/1M129869847EFF0338P2953M2M1.HTML
You are imagining things. Stick to math.

Apparently you are not very good at math either.

http://marsrovers.jpl.nasa.gov/gallery/all/1/m/019/1M129869847EFF0338P2953M2M1.HTML
Not at all. There is plenty of evidence that pyroclastic flows can form dunes just like what we are seeing on Mars.

they're
the
up
Since you are not a geologist, I'm not surprised that you would think so.

camera
Scientists have

on their

dunes,
further
on
was
http://www.jpl.nasa.gov/mer2004/rover-images/feb-26-2004/captions/image-6.html
And you'd no doubt be wrong.

Since the only crater Spirit has been in to date is Sutev, I find this not a little amusing.

http://marsoweb.nas.nasa.gov/landingsites/mer2003/mocs/Images/E03-00012/E03-00012_05.html
Since no one has any respect for your opinions, you opinion of NASA is irrelevant. Oh and stop crossposting, dork.
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February 26, 2004
jonathan wrote:

That is something I have always thought myself. In the Bahamas we call them 'sand waves'. Wherever you find these on Mars, in the bottoms of craters and canyons, they seem to be indicative of the dust and dirt left over from melting ice and standing water, and the wind blowing over the standing water will leave the standing wave dunes as the water evaporates or subsides into the ground. The effects of wind erosion on Mars are grossly 'overblown'. Water is the key player. In many of the very large basins you have huge dunes of very fine sub-micron material which is clearly windblown, probably bacterial remains.

I agree with that sentiment.

You can clearly see them in the bottom of the nearby larger Opportunity crater. It should be possible to see the effects of seepage from the walls of the crater. Some minor seepage effects are visible even in the small Opportunity crater, and clearly the mud flats at the Spririt site are seepage and standing water remnants.

I have completely lost respect for NASA, although clearly I have a lot of respect for the engineers who put these vehicles on Mars. Today's news conference was embarrassing.
Thomas Lee Elifritz http://elifritz.members.atlantic.net
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marsrovers.jpl.nasa.gov/gallery/all/1/m/019/1M129869847EFF0338P2953M2M1.HTML
You would expect? Why? Have you studied their durability in Martian conditions? You can't even claim to know the Martian conditions at the site. The soil chemistry in particular.You are instead leaping to conclusions on the basis of superficial similarity.

Due to the superficiality with which you have approached every other subject you have touched upon here, one would have to be a fool to believe you would be expected to be correct about anything you say when it comes to ANY subject - most certainly including mathematical subjects.

Hah! You have no idea what NASA actually considered nor when.

No. A little technical expertise is what is needed here. Which NASA has - and you most certainly lack. Your particular "common sense" is nothing more than willfully ignorant speculation. You have admitted ignorance of all of the "ologies" required to make an educated conclusion as to what is being seen - yet you have the audacity to chide the people who do not share your ignorance. You have even gone so far as to say the details don't matter because you know with mathematical certainty blah blah blah... Well, the details do matter. What does it do to your gemmule hypothesis if the spherules turn out to be made of basaltic glass? Such a small detail.....

the
up
You can only conclude? That is your description of these people? http://marsrovers.jpl.nasa.gov/people/teamphoto.html
Or perhaps you could name names? Which ones in particular are determined to find non-living explanations? And most importantly - why?

Even Helen Keller could have seen that. All of the MOC images of the Spirit landing site showed that all of the craters in the area are completely dark. You are developing quite a knack for discovering the obvious.

Either you didn't even look or you are playing more games. The MOC images show dark dunes in the crater. This has been known from the very beginning.
http://www.msss.com/mars_images/moc/2004/01/23 /

Lacking respect yourself, this is hardly a loss.
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AAAAARRGGGGGGGGGGGGGHHHHHHHHHHHHHHHHHHHHHHHHH!
Get me out of la-la land!!!!!!!!
Where in the heck to these crazies come from?
Mars???
And how do we get them out of comp.ROBOTICS.mosc and into sci.crazytheoriesfromnonscientistdimwits.theory?
(Present company excepted of course!)
--
- Alan Kilian <alank(at)timelogic.com>
Director of Bioinformatics, TimeLogic Corporation 763-449-7622
  Click to see the full signature.
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Just killfile him. Sorry for the crosspost.
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February 26, 2004
Alan Kilian wrote:

You wait patiently for the data proprietary period to expire.
Or, you can use a filter file. It's very easy, even for you.
Actually, it also helps to ask. Consider it done.
Delete comp.robotics.misc.
Thomas Lee Elifritz http://elifritz.members.atlantic.net
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<Snip>

Why rush? It's a big planet! It's not going anywhere in the foreseeable future. The rovers will not (unless there has been a development I've not heard about) fall apart tomorrow. And remeber - Theres a lot of people trying to get time with these rovers, it's not just ONE person in complete control. It's possible some of the team agrees with you, and got enough time to do a brief exam of the features...Now that some of the other things on the docket are taken care of, maybe these few members are able to say "Hey...we need to go look at this feature again, we need more data!". Saying "NASA" is (insert anything you like here) is a bit misleading ... as with any other organization, there are many hands on the steering wheel!

Until there's some damn hard evidence, geologic ripples is a pretty decent term - They are ripples, and they are on the ground. At this point, without a great deal of investigation, that's about all that can be said about them.
You're damn right...A little common sense IS needed here. I think you're mistaken on who needs to use it though. The science teams are being cautious - You can't just scream "THIS IS DEFINATELY, BEYOND A DOUBT, ABSOLUTELY A WATER-BASED FEATURE!!!!" What the they are trying to do is exhaust the pool of possible explanations, and likely they'll "contrive" some pretty interesting out-there ones (and disprove them - or not), before they make ANY kind of statement as to thier origins. This is good science.
It's not about trying to find what you want to be there...it's about finding what is REALLY ACTUALLY there, how it got there, WHY it's there, and being able to prove all of it, to the vast majority of the scientific world.
<Snip>

Why would you lose respect for scientists doing thier job? YOU can say "This is obviously a feature that could only have been created if there was water and/or life on the surface". YOU don't have a professional reputation as a person of science involved in this exploration. YOU won't get laughed out your workplace for making claims you can't prove. YOU aren't in the international spotlight, with millions of eyes on you. Try and see it from the other side, before you say something like that, please!
-Alex
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