Spirit & Opportunity *3* - ...continued from previous threads

dickbill · 2004-02-13 16:03:07

But it's not a lit by any virtual light. It's just using a texture made from the various microscopic imager exposures. There is no "shading" involved. Being 3D does not imply virtial lights and shading. What they are doing here is analogous to what in the 3D community is called "baking a texture light map".

I understand that. But why is it so obvious that it's a 3d representation ?
The edges right ? they follow the topographic contour. But as I said before, for what I know, the microspcopic imager doesn't focus on objects, it just moves towards them, with the angle problem that I described. Objects directly in axis with the lense will have a change of distance but no angle, while objects off axis, meaning in the edge of the picture, will have a change of angle as well, that means that the superimposition of the pictures won't be nice on the edges. So I understand that NASA prefered to cut the edge artifacts.
Why they just didn't crop nicely a square, I don't know.

Do you have an information that suggest it's a 3d mapping ?

Lars_J · 2004-02-13 16:15:45

dickbill, read SohoBoy's last post. Nasa TV says so.
(As for why I thought so? Because I dabble a bit in 3D stuff in my spare time, and it looked like a 3D model - the edges are a big giveaway)

I don't know the details of how JPL converts a series of images to a 3D model, but JPL guys are pretty tricksy! ;-)

dickbill · 2004-02-13 16:51:24

dickbill, read SohoBoy's last post. Nasa TV says so.
(As for why I thought so? Because I dabble a bit in 3D stuff in my spare time, and it looked like a 3D model - the edges are a big giveaway)

well, NASA's caption says:

"Original Caption Released with Image:
This sharp, high-resolution image shows a rock target dubbed "Robert E," on a rock called Stone Mountain at Meridiani Planum, Mars. It is one of the highest-resolution images ever taken while looking at a rock on another planet. Scientists are studying this area, which measures 3 centimeters (1.2 inches) across, for clues about how the rock formed. The image was created by merging five separate images taken at varying distances from the target by the microscopic imager, an instrument located on the Mars Exploration Rover Opportunity's
instrument deployment device, or "arm". "

no reference to 3d mapping, they just talk about superimposing five 2D pictures...

but anyway, I'm not gonna fight forever on that issue. I am not convinced, that's it.

atomoid · 2004-02-13 20:01:46

Anybody got any ideas on what this mysterious feature is?

A beautiful little crater-like or sand dune crescent feature exists at the foot of the Opportunity lander with undisturbed wind rivulets in it. The rover's wheel almost touched it when it drove by, yet they drove past without taking a closer look or having any comments.

The really intriguing thing about it is that there is some sort of bright white material in the rivulet basins, like windblown grains of light material, perhaps lighter windblown sediments or minerals.

im stumped, but im guessing that if the meteor impacts thaw and wet the subsurface then water might seep to the surface and evaporate leaving mineral deposits behind, the mineral crust particles might blow around and collect in hollows like these rivulets. i'd expect more white material to be collected elsewhere, perhaps it is, but this feature seems anomalous, certainly worth a look with the spectrometer. Seems that it might have an interesting story to tell.
any ideas?
[http://www.freewebs.com/atomoid/CraterCrusties.jpg]http://www.freewebs.com/atomoid/CraterCrusties.jpg

Lars_J · 2004-02-13 23:06:14

Someone asked about that in one of the press conferences, asking if it was frost. But the reply was that it was just brighter red dust. I guess it only looks very bright compared to the surrounding gravel, and especially in the red and infra-red bands.

SohoBoy · 2004-02-14 02:44:47

Do you have an information that suggest it's a 3d mapping ?

No URL, but they showed a 4-5 sec flyaround on NASA TV during the press conference. They must have made up a composite of the various in focus bits of the microphotos and then used it as a texture map. They have some algorithm that can extract 3d data from the level of focus in a series of 2d images which 'focus through' the same scene.

I'm surprised NASA didn't post it as a movie, its quite cool.

SohoBoy · 2004-02-14 02:56:41

Anybody got any ideas on what this mysterious feature is?
A beautiful little crater-like or sand dune crescent feature exists at the foot of the Opportunity lander with undisturbed wind rivulets in it. The rover's wheel almost touched it when it drove by, yet they drove past without taking a closer look or having any comments.
The really intriguing thing about it is that there is some sort of bright white material in the rivulet basins, like windblown grains of light material, perhaps lighter windblown sediments or minerals.

[http://www.freewebs.com/atomoid/CraterCrusties.jpg]http://www.freewebs.com/atomoid/CraterCrusties.jpg

[http://www.keithlaney.com/OCI/V3.jpg]Heres a better view

the crater is obviously not a place where Mars dust generally accumulates, otherwise it would have filled in years ago.. the finest erosional material is on average lifted out by the wind and dispersed. this is supported by the look of the soil microphoto showing the spheres which is 'gritty' rather having the ultrafine grain appearance of the 'mystery soil' seen in the first Spirit microphotos

some may temorarily accumulate when theres a dust storm... I think thats what this is.

Palomar · 2004-02-14 06:23:28

[=http://story.news.yahoo.com/news?tmpl=story&u=/ap/20040213/ap_on_sc/mars_rovers_23]Pump up the Jam, Get the Party Started...

*NASA has upgraded rovers' bandwidth (the article calls them "pokey" rovers, ha ha). Rate is now approximately 5 times dial-up ISP speeds. They're using Mars Odyssey orbiter as a relay satellite.

Also, Opportunity "failed to properly stow its robotic arm," delaying a 30-foot trek which was planned for yesterday until today.

And (quoting story directly): "Opportunity did complete a preliminary survey of a rock outcrop. NASA planned for it next to roll over to a patch of soil believed rich in the iron-bearing mineral hematite, which typically forms in water. Scientists want Opportunity to dig about four inches into the soil, using one of its front wheels to excavate a narrow trench. They hope Opportunity will find minerals that could reveal whether the planet ever was wet enough to support life, a key goal of the double mission."

--Cindy

Palomar · 2004-02-14 07:05:17

[=http://www.space.com/php/multimedia/imagedisplay/img_display.php?pic=h_mgs_opp_site_02.jpg&cap=Image%20taken%20by%20Mars%20Global%20Surveyor%20(MGS)%20orbiter%20has%20identified%20the%20whereabouts%20of%20the%20Opportunity%20Mars%20rover.%20The%20robot%20sits%20inside%20a%20small%20crater%20at%20Meridiani%20Planum%20and%20is%20dutifully%20scanning%20an%20outcrop%20of%20exposed%20rock%20before%20it%20climbs%20out%20of%20the%20crater.%20Image%20credit:%20NASA/JPL/MSSS]You Are Here (large image)

*From space.com's "Astronotes" (updated and archived daily, so have copied and pasted text here):

February 13

Opportunity Spied by Mars Global Surveyor

A "you are here" image taken by the Mars Global Surveyor (MGS) has spotted the whereabouts of the Opportunity Mars Exploration Rover. The robot has been identified from above, sitting in its landing home, a crater 72 feet (22 meters) in diameter within Meridiani Planum.

As the longest "hole in one" shot ever recorded in the history of Mars exploration, Opportunity?s airbag landing system bounced 26 times and rolled about 220 yards (200 meters) before coming to rest in the bottom of the small crater.

Mars Rover Opportunity's landing site, Credit: NASA/JPL/MSS
Click to enlarge.
Also used to pinpoint the location at which Opportunity sits on Mars were pictures taken by the robot itself. By poking its cameras above the crater rim, the rover spotted leftover litter from the craft?s entry, descent and landing - a parachute and protective backshell.

But the real validation was a new MGS image showing the Opportunity lander as a bright feature in the crater. A dark object near the lander is thought to be the rover itself. Given Opportunity?s wheeling around the rim of the crater, subsequent MGS shots of the crater should help identify that, indeed, that dark object is the rover.

---

*Also:

[http://www.space.com/scienceastronomy/m … 40213.html]New insight into Marsian winds

--Cindy

Rxke · 2004-02-14 07:45:14

A bit related to Cindy's posting, [http://www.usatoday.com/tech/news/2004- … unch_x.htm]USA Today posted about the first international interplanetary network.

The rovers cooperate with the European Mars Express orbiter to form a 'network' of communication, making it possible to extend the usable time for communication (the 'window') with the rovers. Very neat example of cooperation ...

dickbill · 2004-02-16 13:35:09

Do you have an information that suggest it's a 3d mapping ?
No URL, but they showed a 4-5 sec flyaround on NASA TV during the press conference. They must have made up a composite of the various in focus bits of the microphotos and then used it as a texture map. They have some algorithm that can extract 3d data from the level of focus in a series of 2d images which 'focus through' the same scene.
I'm surprised NASA didn't post it as a movie, its quite cool.

So it was really a 3D picture ? they should mention it in the caption. Congratulations to Lars that saw that 'trick', but it was rally not so 'obvious' Lars.
By the way you said you use 3d softwares, Lars, may I ask which one ?, we had a thread about this, some time ago between Clark and I. We talked about Bryce, that Clark is using, and Terragen that I prefer. Maybe we could move to discuss that there, if you are interested.

Lars_J · 2004-02-16 14:41:09

dickbill - I have used Bryce, TerraGen, and Truespace in the past - but recently I have been fiddling with writing my own renderer from scratch. (when I have time)

Back to MER... Check out this new RAW image showing the trench that Opportunity's wheels dug: [http://marsrovers.jpl.nasa.gov/gallery/ … 13L0M1.JPG]http://marsrovers.jpl.nasa.gov/gallery....0M1.JPG

Shaun Barrett · 2004-02-16 20:05:07

Wonder what the pale stuff is? ???
More of the material the outcrop's made of?
Carbonate?

atomoid · 2004-02-17 02:40:38

[http://www.lyle.org/mars/imagery/1P1296 … 1.JPG.html]http://www.lyle.org/mars/imagery/1P1296 … 1.JPG.html
look at the rock over to the right at x 800 y 700
the 'bedding planes' are edge on roughly towards us on this rock, but there is a curved flattish tapering tube in a 'W' shape on the surface of the rock which cuts across the bedding plane. If thats just an erosional feature, it's pretty freaky as the bedding does look to be running underneath it. We could do with a better close up to figure this one out.

Yow, it can be hard to see until it pops out at you loud and clear, that really is weird... check it out in 3D -->
[http://www.lyle.org/mars/imagery/stereo … 3774-P.jpg]http://www.lyle.org/mars/imagery/stereo … 3774-P.jpg
[http://www.lyle.org/mars/imagery/stereo … 4487-P.jpg]http://www.lyle.org/mars/imagery/stereo … 4487-P.jpg
if you cant find the "W" consult: [http://www.freewebs.com/atomoid/theW.jpg]http://www.freewebs.com/atomoid/theW.jpg

i first felt this might be some perceptual artifact of a curved part of the bedrock layers (warped layers like occur in terrestrial folded rocks, but that begs the question: tectonic folding on Mars?? Mars doesnt show much history of this and even if so, could the embedded spherules survive this process? but i digress, anyway...)

But it really does look like its pasted on top of the main layer sequence beneath it, especially in the middle of the "W", im baffled...
need a closer look... not just that feature, but also the severely eroded rock just below it.

ACTUALLY, I have a more concise theory on this, but dont spread this or theyll implant a computer chip in my brain, and even you might end up lost or at least with some "missing time"... You know the Enquirer says they found all these skulls on Mars, it was on the front page! skulls all over the place! its true! the "W" written here must be the real reason behind george "W" bush's initiative to go to mars, because I now know, through secret sources in teh russian government, that in 2032 the chinese military creates a time machine and goes back into the past to kidnap george w bush and transpotrs him to mars billions of yaers ago, a time when earth and mars were similar and the harmonic convergences of their contigency-streams can be coalesced into a quantum similarity and thus divergence form an anti-earth was diverted. After transporting GW Bush to mars they reconstructed an anti-bush or shall we say pseudo-bush, from the quantum entanglement of the mars-earth paradigm, this unified dichotomy resulted in a reality that superimposes ours, thus the chinese government controlls Bush in this future Earth to do their own bidding. Needles to say, this non-linear event confuses the whole time continuum (and thats why the remote viewers cant see it), and upon learning of this (via a narrow beam transmission to the present day white house via a chinese defector from the future using the same secret technolgy), the bush administration decides we need to go to mars before 2032 inorder to recover george bush's skull and reconstruct his correct dna resonance and thus have some chance of restoring our universe and timeline. its no coincidence! thats why nasa is keeping the skulls and this "W" a secret! George W Bush, after being beamed to mars billions of years ago, survived just long enough to write his moniker on the rock outcropping you see before you today. His skull lies elsewhere known only to the Enquirer and those who read it. I suggest you buy your copy today! dont delay! enquiring minds NEED to know!! <B>

Visited by Moderator 2022/03/08

atomoid · 2004-02-17 03:41:18

In response to Remcook's point about the lack of haematite where the airbags have bounced, I'm prepared to throw in an explanation.
I mentioned previously that the regions of the regolith affected by the impact of airbags seemed slightly raised, at least to me (maybe I'm wrong, I'm not sure). An explanation occurred to me, which I put forward at the time, based on the notion that the regolith has briny water mixed in with it, quite close to the surface.
I continued by comparing the pressure of the impact of an airbag with the effect of a human foot on wet beach sand at the edge of the sea. Initially, the pressure of a foot causes a 'dry' area around it and then water wells up from below when the pressure is removed.
Imagine a similar effect on Mars. The sub-surface brine, in the process of welling up after the airbag has moved on, might create a muddy briny slurry, which soon freeze dries in the thin cold martian air. This would explain the 'magic carpet', which surprised NASA, and might help with the haematite question too.
I'm assuming the haematite granules are denser than the other material in the regolith. So, when the surface is temporarily converted into a briny slurry, the heavier haematite granules sink while lighter material floats to the surface, thus obscuring the haematite.

The thinner hematite signature in the inside than in the outside of the crater and the airbag bounce marks: [http://marsrovers.jpl.nasa.gov/gallery/ … R1_br2.jpg]http://marsrovers.jpl.nasa.gov/gallery....br2.jpg

---- About the crater being lower inhematite than the surrounding plains:
Perhaps since this hematite is coarse-grained and doesnt get moved around much by wind, its either existed at the surface since it was created or there has been a net wind removal of the fine sediments above and below it, exposing and concentrating the hematite and other larger grains at the top as litter on top of the dust, like desert pavement. (this also means that wherever you find a crater with less hematite in its basin, that crater should be newer than the hematite layer since its been blasted elsewhere and cleaned below the original hematite layer to expose the hematite-poor bedrock). that is, unless the observed redder and higher concentration of hematite in the distance is merely due to visual trick of apparently packing the grains at eyelevel height since they stand up in relief perspective on top of the dust, these exposed hematite grains give a stronger return in the distance than the closer collections of hematite grains do since they make up less of a cross-section of the closer perspective since there is more space visible between grains. in this case the crater might be much older than the hematite which has a uniform distribution inside and outside the crater.

---- About the airbag marks being low in hematite:
-Maybe the airbag impressions remove the hematite signature because the hematite grains got pressed into the surrounding dust, obscuring them from detection.
-Maybe they are very light and were blown away by the bounce.
-Maybe the dust is low in hematite and it got kicked up to coat the hematite grains in dust, reducing their signature.
-Maybe the hematite grains are "sticky" in some way, either prickly texture or static charge, and got picked up and carried off by the airbag material as it rolled over. in such case the airbags should show up bright with hematite.

remcook · 2004-02-17 12:32:06

opportunity dug a trench!

1smlstp · 2004-02-17 22:12:22

Although C-SPAN did not post the link to Tuesday's press conference, they did archive it. Here's the link for everybody that missed it.
NASA Mars Rover Mission Briefing
Tuesday, February 17, 2004 - 36 minutes
[rtsp://video.c-span.org/15days/e021704_nasa.rm]rtsp://video.c-span.org/15days/e021704_nasa.rm

The next news conference will be Thursday, February 19, 2004. They didn't give a time but I expect it would be 9:00AM or 10:00AM Pacific.

Atomoid,
Your "W" story was pretty funny. I hope they go back to it and give it a closer look. Regarding the low hematite in the air bag marks, my guess is the hematite was pushed down in to the soil but it could be any of the things you listed. The fine particles of hematite are great, but I hope they find a big chunk of the stuff that they can study in more depth. I'll be keeping my fingers crossed.

atomoid · 2004-02-18 20:01:07

Some burning questions for further digression:

The odd thing is that Opportunity sees essentially flat rock-free plains around it, no big rocks anyway. Shouldn't we expect many more rocks on the surface since there seem to be plenty of craters from which rocky ejecta from deep below any presumed overlying soils should have been hurled at the time of impact? if so, the rocky ejecta shoudl be somewhere.

Or have the rocks since been covered over by the soil we see today?

Was the Meriadiani surface at the time of the impacts just a bunch of soil (ash, mud, dust) and so no rocks to toss, even from deep down? But if there were no rocks to hurl around, then where did all that soil get created from?

Was Meridiani covered by water (or ice) at the time of the crater impacts? Meridiani is now a very gentle slope so it doesnt seem to be a lakebed unless the surface has since subsided

Shaun Barrett · 2004-02-19 06:42:50

Where are all the breathless commentaries from mission scientists about the photos coming back? Where are the interesting analyses of the soil composition and the rock strata?

Sheesh! Half the people here at New Mars have taken to arguing about Iraq again, it's so quiet at JPL .... !

clark · 2004-02-19 07:12:37

Food for thought as you gaze out yonder window with wonder while our creatures of Mars send back pixles of musings...

Is Mars male, or female. Boy or a girl. Man or woman. Transgender (come on, get with the times! :laugh: ), or what?

My eyesight ain't so good. Anyone got a clue?

Palomar · 2004-02-19 08:55:33

*Perhaps most folks are already aware of this, but at today's main page for space.com is "NEW! Latest Spirit Rover Photo Journal."

This under the "Launcher" tab.

The first pic is titled "Spirit Spies Wavy Bedforms."

"Top Stories" section is featuring new Opportunity Rover photo journal.

--Cindy

RobertDyck · 2004-02-19 09:37:52

I'm still waiting for more technical data from the instruments. The JPL web site has lots of pictures, but it doesn't have any of the technical scientific data I expected; just a link to the Athena Instrument Site. That is the Cornell University web site for the instruments. It has one spectrum from the [http://athena.cornell.edu/the_mission/ins_apxs.html]APXS on Spirit, one from the [http://athena.cornell.edu/the_mission/ins_moss.html]M?ssbauer Spectrometer also on Spirit, and a couple [http://athena.cornell.edu/the_mission/i … ectra.html]Mini-TES images from each of Spirit and Opportunity. The emissivity graphs and numbers are what I really want. The only number from all of this is the ratio of Fe2+/Fe-total from the M?ssbauer Spectrometer. For a guy interested in In-Situ Resource Utilization and producing a Mars regolith simulant, the numbers are important.

Rxke · 2004-02-19 11:13:52

(Despite) Being a total amateur, i have to agree 200% with RobertDyck, though. Those graphs are from the very first measurements, if i'm no mistaken. It's a huge disappointment for me, not being able to see some more of the hard numbers trickling through. "Purty pictures" might be cool, but it would be so much more exhilariting if you knew *what* you are looking at... And read some comments about these measurements. Now all we can do is guessing like 'what's that white stuff down the bottom of the hole Opp. dug?' etc. No way to get an answer...

I thought NASA was to inspire kids into science?

Palomar · 2004-02-20 15:41:01

[=http://story.news.yahoo.com/news?tmpl=story&cid=96&ncid=753&e=10&u=/space/20040220/sc_space/rovermicroscopedetectspuzzlingthreadlikefeatures]Opportunity detects "puzzling thread-like features"...

*They think it may be fabric from lander material:

Sharp-eyed Mars Exploration Rover (MER) scientists are puzzling over very fine thread-like features spotted in the soil at Opportunity's landing site within Meridiani Planum.

The tiny objects are millimeters to a few centimeters in size. While the minds-eye might jump to a number of thoughts as to their origin, caution is the watch-word from Steve Squyres, MER Principal Investigator from Cornell University.

The objects may be from Earth, transported to Mars onboard Opportunity, Squyres said.

"Before I would get too excited about something like this, I would recall that this vehicle [Opportunity] landed using an awful lot of fabric. That fabric took quite a beating in the process of through it [the landing]," Squyres told reporters Thursday during a press briefing at the Jet Propulsion Laboratory (JPL) in Pasadena, California.

*Call is going out for caution to not contaminate the landing sites of future missions.

--Cindy

Rxke · 2004-02-20 16:41:37

Wow!

They'll have to give out the pictures*fast* or there will be a lot of xxx hitting the fan!

i want to see this, too!

(man, my heartrate goes up, all of a sudden...)

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