Mars Exploration Rovers Update - February 13, 2004

formatting link
Update: Spirit and Opportunity

SPIRIT UPDATE: Movin' Towards "Mimi" - sol 40, Feb 13, 2004

Spirit woke up to its 40th sol on Mars to the song "What a Wonderful World" by Louis Armstrong and then proceeded to have a wonderful sol which ended at 7:59 a.m. Friday, PST. After utilizing the miniature thermal emission spectrometer instrument on surrounding soil and completing some pre-drive imaging with the panoramic camera, Spirit proceeded 90 centimeters (2.95 feet) towards a collection of rocks called "Stone Council." The drive lasted less than five minutes. After completing the drive, Spirit imaged several rocks with the panoramic camera, and completed a mosaic of the area in front and to the left of itself.

On sol 41, which will end at 8:39 a.m. Saturday, PST, Spirit will be repositioned in front of the flaky rock called "Mimi" in preparation for placing its instrument deployment device on that rock during sol 42.

OPPORTUNITY UPDATE: Intending to Trench - sol 19, Feb 12, 2004

During its 19th sol on Mars, which ends at 7:41 p.m. Thursday, PST, Opportunity climbed to Waypoint Charlie, where it will complete its initial survey of the outcrop nicknamed "Opportunity Ledge."

The flight team at JPL chose 'Here I Go Again' by Whitesnake as Opportunity's wake-up music.

The plan for sol 20, which will end at 8:20 p.m. Friday, PST, is to do a "touch and go," meaning Opportunity will touch the soil with its instrument arm around the outpost area Charlie, then stow the arm and drive. It will head for an area of soil that the rover's miniature thermal emission spectrometer indicates is rich in hematite. Over the following few sols, engineers intend to use one of Opportunity's wheels to spin into the soil and "trench" a shallow hole so scientists can check what's below the surface early next week. Knowing more about the hematite distribution on Mars may help scientists characterize the past environment and determine whether that environment provided favorable conditions for life.

Scientists and engineers will pore over the data collected along Opportunity Ledge this week to target a return trip to the most interesting science locations along the outcrop later next week.

Reply to
Ron
Loading thread data ...

[...]

Any guesses what they will find in the trench ? I bet they will not find a lot of hematite below the surface, because it is concentrated in the spheres and the spheres are only lying on the top. There are no sand dunes like at gusev crater, because the spheres prevent them from forming - is this possible ? Could there be an other reason as density that prevents these spheres from beeing burrowed below the dust, maybe some electrostatic effect ? If the spheres were very light the wind would blow them to dunes, if they were heavy they would be buried below the dust, and there is a lot of dust falling down if you wait long enough...

Reply to
Carla Schneider

"Carla Schneider" wrote in message news: snipped-for-privacy@yahoo.com...

Actually, if there is a little soil movement activity, or if the spheres are moderately dense, the movement of sand could be enough to keep them on top. Try placing various sized objects in a container and shaking it- the smallest objects will sift to the bottom and the larger ones will rise to the top. These spheres could be going through a similar process, keeping them on the upper layer of regolith. I am of the idea that the spheres are from one of three possible origins: a) an impact in mud and the thin air and low gravity allow them to solidify and fall back to the ground. The spheres might have been heated in this sort of event, hardening them. b) accretion from some geological process, perhaps through the presence of water. c) biological activity.

If a) is true, then you would expect that these spheres might be very old, when it was more likely that water was extant on the surface. But, permafrost theories also say that there might be occasional torrents when impacts or other events release the water bound up in permafrost. If b) is true, you might expect a broader range of sizes, although some type of sorting process might also be at work. However, the look at the layering of the rocks and the fact that spheres are embedded throughout seems to indicate that they were present before the rock layer were formed. If true, and if the rock is sedimentary (as it appears to be) then it leads you to think that the spheres are resistant to the action of water and from an earlier period. Of course, some suggest that the spheres might have formed inside the rock, but my gut feeling (not very scientific!) is that this should lead to various concentrations of these spheres through the rock, not the sparse concentration we see. In other words, some clusters of the spheres should occur if they were formed in the rock. If c) is true, then we have found what we are after. I notice that many of the spheres have odd characteristics, such as "tapered" ends, or small depressions. Could these be traces of some structure that an original organism had? Another possibility is that some outcrop of mineral had crumbled and rolled downstream in the past, wearing away and producing smooth "pebbles". Note that this can also produce a sorting mechanism, as the movement of water and the mass and size of the stones could select out the ones in a narrow range of cross sections and masses. If true, we could expect to find other areas with lots of spheres of different diameter- larger or smaller overall. Note that I do include the effects of water in most of my ideas. Well, enough rambling.

Cheers!

Chip Shults

Reply to
Sir Charles W. Shults III

Hi Carla

"Carla Schneider" skrev i en meddelelse news: snipped-for-privacy@yahoo.com...

Crushed basalt - judged on the general dark colour of the tracks the rovers leave behind. As to the hematite I believe that - from whatever wet watery circulation, it is a surface-precipitate. As a surface-feature it is vulnerable to the windy abration that also may scatter it as dust to other parts of the surface.

That would make the general raised values an attribute to wind-action depositing the stuff at one favoured spot - that seems less likely.

Wouldn't that imply different modes of origin for the spheres - the light-colored solid exposure seems to be composed of spheres but are low in hematite.

No. But there has to be a certain amount of moveable sand - it may have blown elsewhere

I don't think so. I have 'so to speak' introduced electrostatics to account for the cohesion of the soil we saw at the early pictures. I ment it as a substitusion for chemical reactions that has not happened, but would have, had water been present - because of the large surface-area of (and presumably large stock of) dust. It may however reveal a cerious gab in my understanding of chemistry.

Judging geology by pictures has a lot of drawbacks - it's not easy to 'see' the density of one sphere.

Carsten

Reply to
Carsten Troelsgaard

The spheres are not only lying on the top -- they are the main constituent of many of the thin layers. Most of the microscopic images show layers of small, tighly packed (though not clear how firmly cemented) spherules. Some, it looks to me like mostly the somewhat larger ones, are weathering out. It looks to me like most of the outcrop -- at least the one they have imaged most closely -- is made of the spheres plus matrix of much more fine-grained material, which (presumably) when it weathers turns into the fine sand in which the loose spheres lie.

Reply to
Richard I. Gibson

I think maybe there are some clues from the overhead imagery to the formation of the units we're seeing on the ground. What those clues mean, I'm not sure... *smile*... but there are clues.

I've looked at the enhanced version of the last DIMES images many times, and I get the impression that something flowed across the flat plain, from south to north. There are several features that look like very low flow fronts -- they're roughly lobate and have subtle surficial distortions that would indicate the bottom-to-top flow in reference to the image.

These flow features don't look like the standard fluidized ejecta you see around Martian craters. They look a *lot* lower, less relief. And there's no conveniently-located craters (especially of the right size) in the context views I've seen to have created such a pattern due to ejecta.

So, there seem to be landform cues for very thin material flow across the region. It certainly doesn't look like aeolian dust movement, it looks like ground material flow. Now, whether this represents extremely thin, runny magma or flooding by water or some other fluid. that's a mystery, at present. But it ought to be taken into consideration when trying to analyze the origin of the surficial materials...

Doug snipped-for-privacy@NOSPAM.mn.rr.com

Reply to
Doug...
[snip...snip...]

Sponge-like critters would seem to be a possibility. They evolved very early here and have fossilized remains that are similar to some of the fragments.

formatting link
Of course, there's always the "Face on Mars" problem: Look at enough chunks of rock and eventually you'll see something recognizable. Would be cool, though...

Reply to
Rich Webb

Gee Carla, where did you get that information? Even the JPL scientists have said that they have had trouble taking readings from the spherules ecause of their small size. They haven't said what they are composed of. In addition, there is no reason to assume that the spheres are only sitting on top of the soil. Let's wait until they conduct the trenching and report on their analytical results before we all make such pronouncements, shall we?

Actually if you look at the picture at the following link. you will see small dunes in the foreground. Since the rover has yet ot even leave the crater, nad since the dunes you refer to at Gustev crater are ver small, I see no reason to expect that these dunes will not be found at the opportunity site as well.

Reply to
George

Did you see the colored map of hematit concentration ? No hematite where the airbacks compressed the soil, that means the spheres have been pressed below the dust and the spheres are the carrier of hematite mineral.

It was a guess, I wanted to file here. So if I am right I will be able to say I knew it in advance.

???

Lets see. usually a crater should be a place to expect such dunes if there are any. There are no dunes visible that bury the spheres.

Reply to
Carla Schneider

If they're ancient I wouldn't expect the spheres to show a diversity of condition, some badly broken, some very pristine. The Spirit site looks ancient, this just doesn't to me.

Isn't soil on earth built by repetitive biological cycles? Wouldn't we expect to see fossilized examples of the biology that built the soil in the bedrock, sedimentary bedrock?

When I look at this pic I can't help thinking we're seeing an entire life cycle. Smudges of formation, mature forms and broken forms.

formatting link

I really wish the rover would take a spin outside the crater to get some good images of the surrounding field.

I live along the Florida everglades, it's a 40 mile wide river of grass following the flow of mostly underground water. I can't help but think the soil, spheres and smooth flowing terrain around Opportunity is a result of underground water or ice.

Jonathan

s

Reply to
jonathan

Yes the spheres were pressed below the soil surface. That does not necessarily mean that the hematite originated from the spheres. Why? Also note that the uppermost topsoil itself was disturbed. In addition, and spectral analysis of the rock outcrop from which the spheres apparently orginated was very low in hematite.

I can understand that sentiment. However, I'd be careful about making statements prematurely. The often times have a habit of coming back to haunt you.

Oops, sorry. Here is the link.

formatting link
Download the image, then open it in the image processing software of your choice (I use Adobe Photoshop, and Corel PhotoPaint). Zoom in on the far right-hand side of the image,and you will see small dunes. You will also note that the soil appears to be thicker in this area. Also note that not only is the soil disturbed by the airbags low in hematite, but a large area of undisturbed soil from the center to the right of center in the image also is low in hematite. So I would have to say that in my opinion the areas where the hematite is highest in concentration must have some other unique feature that is allowing the hematite to be concentrated there.

As appears to be the case with this crater, it seems that the wind blows the strongest in the area where the outcrop is exposed - since it has been denuded of its soil, I would think this would be likely. Where the wind speed drops, one would expect it to drop its load of sediment. One would expect to find dunes only near the top of the crater away from the outcrop. Low and behold, there are dunes in the right-hand side of the image shown in the link, above, at the top of the crater. I would expect that soil comprising these dunes may have originated from the exposed area of outcrop. Whether these dunes have buried any spheres or not is unknown since they have not taken the rover over to that area to investigate.

Interesting web site. Of course, it has nothing to do with this newsgroup, or the subject of this thread.

Reply to
George

Am I missing something here? What pictures are you using to come to that conclusion? If you look at this very close-up image, you will see spheres in a range of conditions, from almostr pristine to pitted and broken:

formatting link

Most soils on the earth are formed from chemical and mechanical weathering:

formatting link

Why?

Hahahahahahaha!!! Sorry, I couldn't help but laugh. What you are looking at are spheres in various stages of mechanical decomposition. They are inorganic mineraloids, dude.

Have some patience. That is on the rover's agenda. They also plan to travel to a much large crater that is much closer to Opportunity than the crater that Spirit is trying to reach. I suspect Opportunity may actually reach that crater before Spirit reaches its crater.

Well, there is certainly no evidence one way or another for that idea. If you look at an image of the region, you will note that it is a large crater that has been nearly completely filled with soil/sediment/regolith:

formatting link
Also note that there are younger craters that have impacted this filled region, which has in turn filled the older, much larger crater. This fact, aside from the fact of the presence of hematite, and the flatness of the terraine, is one of the reasons why this site was chosen for exploration.

Reply to
George

" George" skrev i en meddelelse news:8mEXb.43325$ snipped-for-privacy@bignews5.bellsouth.net...

snip

Do you have to, George?

snip

I have seen pictures of massive landslides that grades into what look like a fluidized flow. To consider water and ice involved does not pose a problem to me.

Carsten

Reply to
Carsten Troelsgaard

" George" wrote

The relative cross-section of the spherules in the matrix facing the camera is about 2%. They are much more concentrated on the ground, particularly in oblique views.

The spherules tend to come out bluish when visible RGB images are combined, leading to the moniker "blueberries.: It's interesting to compare such a composite to the hematite map produced by the TES.

formatting link
The more red areas in the right image (hematite) tend to correspond to the more blue areas in the left image (spherules). Conclusion: spherules = hematite.

Now what fun would that be?

Joe

Reply to
Joe Knapp

Yes, reading comprehension. I'll speak more slowly this time.

If...they...are...ancient...I ...would...not...expect...some..to be...pristine.

Reply to
jonathan

Yes, I do. :-)

But we see the same phenomenon in landslides in desert regions on the earth. There is evidence that some large landslides will behave as a fluid due to the creation of a layer of compressed air between the landslide material and the ground upon which it is sliding. Such a layer acts like a lubricant that reduces friction, and will allow the slide to behave as a fluid. In the case of Mars, the air would consist of the CO2 atmosphere. Now, I am not saying that water doesn't exist on Mars. Obviously it does, at least at the poles. And of course, we have all seen some evidence that there may be ground water, and/or frozen water in the subsurface. What I am saying is that there are other explanations for the fluid appearance of these landslides on Mars.

Reply to
George

It has been my understanding from reading the interviews of the project scientists that they were referred to as blueberries because of their shape and size, not because of their color. In addition, there is no way that you can look at the picture you posted above and say that the blue color is due to the spherules simply because you cannot even see then at that resolution. On the other hand, you can look at this image and get a clearer view of the color of the spherules.

formatting link

Here is a link to the TES data collected by the rover:

formatting link
The data is superimposed onto the panorama of the outcrop and edge of the crater. If you will note that in the center of the image is the area of the outcrop first examined by the rover. That area had a lot of spherules on the ground around the outcrop (the outcrop referred to as "stone mountain"), within the outcrop itself, and below and above it. Note that this area is hematite-poor. And the outcrop itself was hematite-poor. For verification, please note this image of the area I'm referring to:

formatting link
formatting link
You should also note that there are very few images sent back by opportunity of the soil in which the spherules were not present, yet there are large areas that appear to be hematite-poor. As I've said before, I think is it too early to say that the spherules are composed of hematite. Looking at data brought back from Apollo 14, similar granular spherules were found at that site that turned out to be composed largely of plagioclase. I think I will wait for more data before reaching a firm conclusion regarding the spherules.

Well, we can all speculate all we want to, but my experience with speculation is this: Don't assume, that way you won't make a fool out of you and me! :-))

Reply to
George

" George" wrote>

Mark Lemmon: "We've looked at the floor of the crater itself and it's exciting. In particular, this area is covered by finescale sandgrains and these irregular grains coming down from the outcrop potentially and the most spectacular are these rounded spherules being called blueberries because they're relatively bluer than their surroundings." (Thursday, Feb. 12)

If you miss them, a lot of the press conferences are archived on C-SPAN; unfortunately they don't have that one though.

But you can see the blue color at that resolution, which the blueberries are in such an RGB composite (with overemphasized blue).

verification,

Not really, outside the airbag bouncemarks:

formatting link

Similar? They were over ten times smaller than these and were made of dark glass!

But is speculation, particularly based on current data, equivalent to assumption?

Joe

Reply to
Joe Knapp

Why? Very little aside from wind is occuring that can alter anything on the surface. It certainly doesn't rain. And any frost action is extremely limited in scope and intensity. The surface of most of the planet has been left unaltered, except for wind effects and the occasional meteor impact, for perhaps billions of years. The landscapes you are seeing at both sites are very, very old.

Reply to
George

That is absurd. If that were the case, the cratering would be much more uniform planet wide. There is wide scale evidence of surface subsidence via ice removal and water outflow almost everywhere on the planet. That almost certainly has modified the surface.

You are an idiot, crackpot. Give it up.

Thomas Lee Elifritz

formatting link

Reply to
Thomas Lee Elifritz

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.