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Unmanned Spaceflight.com > Mars & Missions > Past and Future > MER > Spirit
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fredk
My God—it's full of stars! tongue.gif wink.gif laugh.gif
Tesheiner
I almost jumped from my seat!
When the image began (slowly) being displayed, line by line, I said to myself: holy sh**! The milky way!

laugh.gif
SpaceListener
I don't seem it is full of stars but it is the soil. You can see different type of soil along with small stones.
nprev
Yeah, even once the noise is removed I bet that white patch is still gonna look pretty sparkly. Perhaps a small deposit of halite, or maybe even teeny little quartz crystals?
alan
From about a week ago:

01935 p2571.22 13 0 0 0 0 13 pancam_bright_soil_HiRISE_L234567Rall

Does HiRISE have sufficient resolution to see the patches of bright soil in front of Spirit?

CosmicRocker
There is a little more detail here with regard to the composition of this latest mess.

"Analysis indicates this material consists of differing amounts of ferric sulfate, calcium sulfate, silica and other constituents."
Hungry4info
QUOTE (alan @ Jun 19 2009, 07:32 PM) *
Does HiRISE have sufficient resolution to see the patches of bright soil in front of Spirit?


I'm sure it does. HiRISE was able to resolve Opportunity's tracks way back when it first arrived at Victoria.
fredk
QUOTE (CosmicRocker @ Jun 20 2009, 08:00 AM) *
There is a little more detail here...

For those who haven't noticed already, that's a verbatim rehash of the official update here.

I agree hirise could easily spot the white stuff. Being very bright material helps (a camera can spot sub-pixel-sized structures if they are bright enough - think about imaging stars, for example).
erpol
QUOTE (RoverDriver @ Jun 15 2009, 03:43 PM) *
Pan di Spagna is translated as "Sponge Cake" but it does not pay justice to this delicious pastry base.
Wonderful! From "pan di spagna" to "pan di spugna". smile.gif
QUOTE (RoverDriver @ Jun 15 2009, 03:43 PM) *
Now, can we go back to the topic at hand, please? smile.gif

Paolo

Right you are!

There is a thing that worries me, about the mess Spirit is in.
You (your team) got the DE to mimic the ground Spirit is into.
Then you put the terrestrial Spirit in the testbed and you recreate the Mars situation putting DE all around the Rover, the closest as possible as the situation on Mars.
Then start to move the rover according to the strategy you planned.
It's very unlikely you succeed at the first attempt, smile.gif so you carry Siprit out of the testbed, rearrange the soil, put Spirit back in and then re-recreate the mess Spirit is in.
How can you be sure to recreate the same situation as the previous one?
And at the 1000th attempt? Don't you risk to have a substantially different situation from the first one?

I'm sure, anyway, that you thought about it. How did you resolve it?

Ciao,
Ermanno
eoincampbell
QUOTE (alan @ Jun 19 2009, 05:32 PM) *
Does HiRISE have sufficient resolution to see the patches of bright soil in front of Spirit?

Tyrone seems to show up very well in HiRISE images...
centsworth_II
QUOTE (erpol @ Jun 20 2009, 11:20 AM) *
How can you be sure to recreate the same situation as the previous one?
And at the 1000th attempt? Don't you risk to have a substantially different situation from the first one?

With all the recent talk about deserts, it's easy to see the testbed setup as a cake recipe. Once you know the recipe you can recreate it as many times as you want.

I'm sure there are plenty of X factors involved both on Mars and in the test bed. The test bed could be set up ten times to test a maneuver and there could be some variation in outcomes, but hopefully with the same general result. If the same outcome does not reproduce on Mars, its 'back to the test bed' and maybe the same setup, maybe a different one.

After each attempt on Mars, a new test bed setup will be required to reproduce the new situation on Mars. The test bed can be set up any way the testers want. They don't have to rely on chance for a certain setup to occur.
James Sorenson
QUOTE (CosmicRocker @ Jun 19 2009, 11:00 PM) *
There is a little more detail here with regard to the composition of this latest mess.

"Analysis indicates this material consists of differing amounts of ferric sulfate, calcium sulfate, silica and other constituents."


Seems that we are dealing with Diatomaceous Earth on Mars. It looks to have a similar or same composition as what Spirit measured and the composition of DE. Has this been mentioned?
RoverDriver
QUOTE (erpol @ Jun 20 2009, 08:20 AM) *
...
How can you be sure to recreate the same situation as the previous one?
And at the 1000th attempt? Don't you risk to have a substantially different situation from the first one?
...


Very, very good question. I tried to reduce the variables as much as I can. Although the soil under the right side is different from the soil under the left side of the rover, I believe we have a soil compound that can reproduce the two soil mechanical behaviors depending on how the simulant is tamped down, and this can be reproduced consistently. Since the soil is all the same there is no need to keep two different soil simulants separated. The sandbox is in an A/C area and the rover will be placed in the same configuration each time in the 8'x12'x2' box we built (set at about 12 deg roll).

Soil simulant material (about 4000lbs) should be coming in on Monday!

Paolo
CosmicRocker
QUOTE (fredk @ Jun 20 2009, 10:32 AM) *
For those who haven't noticed already, that's a verbatim rehash of the official update here. ...
Yeah, I hate web sites such as that one, which simply plagiarize stuff written by NASA or JPL because it is in the public domain. Instead of giving credit to the organization that actually wrote the piece, they further their deception by insinuating that it was the work of their staff. I'm really annoyed with myself for linking to a page from that site. mad.gif

QUOTE (James Sorenson @ Jun 20 2009, 03:20 PM) *
Seems that we are dealing with Diatomaceous Earth on Mars. It looks to have a similar or same composition as what Spirit measured and the composition of DE. Has this been mentioned?
I'm not sure about that, James. Diatomaceous earth is almost completely silica, with the other components occurring as impurities. The material bogging down Spirit was originally described as a salt (ferric sulfate). We are now hearing about other components of the mixture, but there is no indication that silica is a major component.
ElkGroveDan
QUOTE (RoverDriver @ Jun 20 2009, 04:41 PM) *
Soil simulant material (about 4000lbs) should be coming in on Monday!


And if you find a solution very quickly, as a cost saving measure the remainder will be used in the JPL kitchen for the next few months. ("These breakfast scones are awfully dry, a lot like the corn bread they served at lunch yesterday....")
RoverDriver
QUOTE (CosmicRocker @ Jun 20 2009, 08:23 PM) *
...
I'm not sure about that, James. Diatomaceous earth is almost completely silica, with the other components occurring as impurities. The material bogging down Spirit was originally described as a salt (ferric sulfate). We are now hearing about other components of the mixture, but there is no indication that silica is a major component.


Sorry for repeating myself, but want to make sure it is understood that the choice of materials for the soil simulant is only for convenience, not because we believe the soil on Mars is silica, much less Diatomaceous Earth.

Paolo
brellis
Clearly, future rover wheels need to have taste buds. smile.gif
erpol
QUOTE (RoverDriver @ Jun 21 2009, 02:41 AM) *
Very, very good question. I tried to reduce the variables as much as I can. Although the soil under the right side is different from the soil under the left side of the rover, I believe we have a soil compound that can reproduce the two soil mechanical behaviors depending on how the simulant is tamped down, and this can be reproduced consistently. Since the soil is all the same there is no need to keep two different soil simulants separated. The sandbox is in an A/C area and the rover will be placed in the same configuration each time in the 8'x12'x2' box we built (set at about 12 deg roll).

Soil simulant material (about 4000lbs) should be coming in on Monday!

Paolo


This (the rover placed in the same configuration) is what worries me. I's not only a matter of angles, or soil composition.
I saw the wheel (R, L or what, I don't remember) is half buried.
I'm worried that even some mm higher of lower, in the test simulation, will make a difference from the real situation on Mars.
Not to speak about the rock (if it's a rock) under Spirit.. This is an additional problem, in the testbed. That one has to be placed in the same position every time. But AFAIK you don't know exactly where it is.

Oh, well... Anyway I wish you and your team good luck. I'm.. hmm... ehm.. "tifando per Spirit" with all my strenght.

Too bad smile.gif I won't hear from you for a couple of weeks, but I'm taking an early holiday.

Ciao,
Ermanno
djellison
QUOTE (erpol @ Jun 21 2009, 08:38 PM) *
I'm worried that even some mm higher of lower, in the test simulation, will make a difference from the real situation on Mars.


No one's going to perfectly replicate the conditions and come up with a perfect sequence to extract Spirit. It's about approximations and broad techniques and ideas. It work at Meridiani for Opportunity smile.gif
RoverDriver
QUOTE (erpol @ Jun 21 2009, 12:38 PM) *
...
I'm worried that even some mm higher of lower, in the test simulation, will make a difference from the real situation on Mars.


The most promising techniques will likely be tried more than once. If small differences in setup will make a large difference in result we will know it.

QUOTE
Not to speak about the rock (if it's a rock) under Spirit.. This is an additional problem, in the testbed. That one has to be placed in the same position every time. But AFAIK you don't know exactly where it is.


We were able to measure the approximate position of the tip of the rock and its size. What we do not know, and prbably it is more important, is how much resistance the rock is opposing to Spirit's weight. Again, we will try to test multiple values for this unknown and determine if it is an important factor.

Paolo
CosmicRocker
I think we've all pretty much noticed this, but I can't say I recall having seen it put into words. Spirit is bogged down at a boundary between two different soil types. Most of the wheels are spinning-in/churning-up non-cohesive soil. I recall that one wheel, probably the faulty right front wheel, remains well planted on cohesive ground. Does the right middle wheel have partial footing on the cohesive ground?
Astro0
That's an interesting point.
Here's the underside shots again...
Click to view attachment
If the RM wheel (on the left in the above images) is on partial 'cohesive' ground, could they tell from the resistance (current) difference from the LM wheel to distinguish the variation in soil type?
RoverDriver
QUOTE (CosmicRocker @ Jun 21 2009, 09:46 PM) *
I think we've all pretty much noticed this, but I can't say I recall having seen it put into words. Spirit is bogged down at a boundary between two different soil types. Most of the wheels are spinning-in/churning-up non-cohesive soil. I recall that one wheel, probably the faulty right front wheel, remains well planted on cohesive ground. Does the right middle wheel have partial footing on the cohesive ground?


Currents unfortunately they are influenced by the attitude of the rover but mostly by the fact the LF wheel is not active. But a few sols ago we took color subframe PCAM that would tell us if the RM is on good soil. From the RHAZ it appears that the RR wheel is churning up dark soil, indicating a different type of soil vs. the left side. The right side appears to provide more traction, and we are trying to replicate the difference between the right side and left side soil in the sandbox.

Paolo
CosmicRocker
QUOTE (Astro0 @ Jun 22 2009, 01:01 AM) *
... Here's the underside shots again... If the RM wheel (on the left in the above images) is on partial 'cohesive' ground, could they tell from the resistance (current) difference from the LM wheel to distinguish the variation in soil type?
Thanks for those, Astro0. It's hard for me to see much regarding the RM wheel, but it seems clear that it is not on solid footing. sad.gif

Considering how well the MIs imaged the underside, I was wondering if the robotic arm would be able to put the MI in a position to image the wheels and rocker-bogey suspension from an oblique, side view. It seems that it would be useful to know the rocker-bogey geometry. Apart from directly imaging it, is there another way to know the suspension's attitude?

QUOTE (RoverDriver @ Jun 22 2009, 08:05 AM) *
... From the RHAZ it appears that the RR wheel is churning up dark soil, indicating a different type of soil vs. the left side. The right side appears to provide more traction, and we are trying to replicate the difference between the right side and left side soil in the sandbox. ...
Well, that's a bit of encouraging news that we can all hold on to. smile.gif Thanks, Paolo.
briv1016
Did Spirit not downlink anything on sol 1944? No data on the tracking site and no images on Exploratorium. sad.gif
djellison
It's only 6am on 1945 now. You shouldn't start wondering where downlink is for 48 hrs.

IF we all jumped every time we didn't get every iota of indication of normality every day....this forum would fall apart very quickly.
PaulM
QUOTE (RoverDriver @ Jun 17 2009, 04:34 PM) *
For those of you that have a DE pool filter, get a container about 10"x10"x6". You need to have about 4" of DE in the box. Now fluff it up using your hands as if you were tossing a salad with tongs. Although DE is not toxic it will dry up your hands, so use gloves if you want. Once it is fluffed up, using one open hand try to move around in the DE slowly. You will see that the DE behaves almost like a liquid.

Paolo

The ground that Spirit is stuck in seems to have the physical characteristics of quicksand? Does anyone have any idea of how thick the deposit is?

I wonder if thicker deposits of this materiel could represent a hazard for astronauts?
Phil Stooke
Maybe if they stood in one place and shuffled their feet thousands of times...
Phil
BrianL
QUOTE (PaulM @ Jun 23 2009, 06:26 AM) *
I wonder if thicker deposits of this materiel could represent a hazard for astronauts?


Hmm, we wouldn't want astronauts having to go someplace that might be considered unsafe. wink.gif

Umm, I'm speaking of course about an unmanned manned mission here. Just to be clear on that. biggrin.gif
RoverDriver
QUOTE (CosmicRocker @ Jun 22 2009, 10:14 PM) *
...
I was wondering if the robotic arm would be able to put the MI in a position to image the wheels and rocker-bogey suspension from an oblique, side view....


The view that Astro0 posted is from an oblique view. The turret was almost dead center relative to the rover. Since the turret was very close to the shoulder, its position cannot be changed that much. To get an even more oblique view I would need to have the turret further out therefore increasing the distance between MI and wheels...

Paolo
fredk
Thanks for the info as always, RoverDriver. Sorry if you meant to answer this above, but it wasn't clear to me. Is it possible to reach the MI around and image the RM (or LM) wheels from the outside? Perhaps it's just a question of whether the shoulder azimuth joint can swing that far to both sides? (I wish I had a model to try out moves like this!) Or did you mean that that was possible, but the MI-middle wheel distance would necessarily be too great to get a useful image?
fredk
A bit of an update from New Scientist:
QUOTE
Further analysis suggests the rock-like object is just barely touching the underside of the rover but is not bearing any weight.

The rock also appears to be resting on top of the Martian soil, suggesting Spirit might be able to press it further into the ground if it does come into contact with the rock. "When we do start to move [Spirit], it's likely that rock won't be a hazard or obstruction. Right now it's a concern, but it's not considered a serious concern," Callas told New Scientist.
RoverDriver
QUOTE (fredk @ Jun 23 2009, 06:30 AM) *
Thanks for the info as always, RoverDriver. Sorry if you meant to answer this above, but it wasn't clear to me. Is it possible to reach the MI around and image the RM (or LM) wheels from the outside? Perhaps it's just a question of whether the shoulder azimuth joint can swing that far to both sides? (I wish I had a model to try out moves like this!) Or did you mean that that was possible, but the MI-middle wheel distance would necessarily be too great to get a useful image?


The IDD azimuth joint does not cover that area unfortunately and even if it did the distance to the middle wheels would be too large.

Paolo
alan
The Calypso panorama so far
Click to view attachment

This is from images downloaded as of June 13. All the images for the remaining 6 columns of the panorama appear to have been taken but I haven't seen much progress in downloading them since then. I thought with the additional power available since the solar panels have been cleaned and the use of the second Mars Odyssey pass in the morning we would be seen more data downloaded. What is responsible for the delay? Is there other data from the other instruments, for example the MiniTES (is that still functioning?), that are using the bandwidth?
briv1016
I've been keeping track of the onboard data after every sol since the embedding and have found some peculiarities. Keep in mind the following doesn't account for the "unexpected sequences." As of sol 1945.

Observations table was last updated at 2009-06-23 21:33:37
EDRLevel table was last updated at 2009-06-23 18:38:47


Sols________Onboard/Pending Deletion

1890-1894___4/0
1895-1899___0/0
1900-1904___0/0
1905-1909___0/0
1910-1914___3/0___(All images from the Calypso Pan)
1915-1919___2/0___(All images from the Calypso Pan)
1920-1924___1/0___(All images from the Calypso Pan)
1925-1929___14/2
1930-1934___314/74
1935-1939___579/130
1940-1944___863/261
1945-1949___116/0


It seems like there intentionally keeping some really old data?
PhilCo126
That's a superb color panorama Alan, but I'm pessimistic about Spirit's chances as the rover has been stuck for almost 50 sols huh.gif
( Oppy was stuck at Jammerbugt during 10 sols (833-843 in June 2006), and got out Purgatory Dune after 38 sols (446-484) in June 2005... looks like the 6th month of the year has something to do with it wheel.gif )
fredk
I'd say there's not much reason yet to be pessimistic (or optimistic for that matter), since they haven't even tried the extraction maneuvers in the full sized test bed on Earth, never mind Mars! If they make several attempts on Mars without success, then we can start to worry.
RoverDriver
QUOTE (PhilCo126 @ Jun 24 2009, 11:52 AM) *
...
( Oppy was stuck at Jammerbugt during 10 sols (833-843 in June 2006), and got out Purgatory Dune after 38 sols (446-484) in June 2005... looks like the 6th month of the year has something to do with it wheel.gif )


I am quite aware of the time scale for this anomaly, but I'm going to try to put it in perspective for you. Purgatory was driving 40+ m into a tall ripple. The obvious maneuver was put the vehicle in reverse and use the downslope to extricate the rover. At that time resources were plenty, very little red-tape, everything was done quickly and efficiently. Jammrbugt was "just" a 20m drive into a ripple. It was almost identical to Purgatory, we knew what we needed to do and in a few Sols we were out. Opportunity had all 6 driving actuators working properly.

Here:

1) rover has downslope vector at 90 deg relative to the direction of motion (cannot use gravity to help extricate the rover)
2) only 5 wheels are active, and 1 boat anchor
3) LM wheel stalled
4) possible high centering
5) resources are much more streamlined
6) there is no obvious maneuver to try

I am not trying to find excuses, but I hope you appreciate the scale of the problem. And I'm not going to even list all the stumbling blocks we have had so far.

Paolo
SpaceListener
Yes I agree that this case is the most serious of all past rover stuck.

My last hope is to try to rotate as much as possible on both directions, the wheels will sink mostly on the West side (the "touching stone" is East side of point of equilibrium) until any of the wheels catch a firmer soil to provide exit traction.

Of course, no hurry to perform and finish the testing, a good break between tests will provide a good food of thought in solving the problem. Good Luck smile.gif
BrianL
Well, when you put it like that, Paolo, I can see why nobody should be pessimistic. biggrin.gif
briv1016
New section added to the MER site regarding Spirit's embedding.

http://marsrovers.jpl.nasa.gov/newsroom/free-spirit.html


BTW: How long have the rovers had a Twitter page?
HughFromAlice
QUOTE (RoverDriver @ Jun 25 2009, 11:52 AM) *
I am not trying to find excuses, but I hope you appreciate the scale of the problem.


While we're all worried, gotta say you guys are doing a GREAT and thorough job. IMO the cleaning events have been critical in allowing quality thinking time. Test, retest and reretest...... Who cares if it is mid August - as long as it isn't August 2010!
ustrax
Calypso, Troy...aren't we on the wrong side of the planet?...what's next? Ithaca?... smile.gif
Tesheiner
That's from sol 1943. smile.gif

> 01943::p2585::22::13::13::0::0::2::28::pancam_ithaca_townies_L234567Rall
SpaceListener
An interesting posted article at JPL WEB site.

Mars Rover Yielding New Clues While Lodged in Martian Soil
Spirit entered an area composed of three or more layers of soil with differing pastel hues hiding beneath a darker sand blanket.

"The layers have basaltic sand, sulfate-rich sand and areas with the addition of silica-rich materials, possibly sorted by wind and cemented by the action of thin films of water. We're still at a stage of multiple working hypotheses," said Arvidson. "This may be evidence of much more recent processes than the formation of Home Plate...or is Home Plate being slowly stripped back by wind, and we happened to stir up a deposit from billions of years ago before the wind got to it?"
RoverDriver
Sorry for not being around yesterday, but we finally got all the material and equipment to fill the testing rig. It was a dirty job but somebody had to do it. I had tremendous help from my colleagues that swapped teh controls of the rovers for heavy lifting, wheel barrows, dust in their hair and all over their clothes. We are half whey done with filling the testing rig, hopefully that will be completed today. I'm sure pictures will be posted on the JPL web site. I will update you over the weekend.

Paolo
ddeerrff
Looks like here:
http://www.jpl.nasa.gov/freespirit/
alan
The latest update has energy production at 945 watt-hours with atmospheric opacity (tau) of 0.480 and an improved dust factor of 0.834.

Anyone remember what energy production was just after she land?

SpaceListener
The highest was over than 1,000 Watt-hours when Spirit was at the top of Columbia mount during the summer time. When it landed, it was between 900-800 watt-hour
Shaka
Seen on bumper sticker: FREE THE SPIRIT SIX

Seriously though, how many more watt-hours do we need to prove cold fusion?
cool.gif
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