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View Full Version : Big ole hunk of ice?!



CrzyWeazl
2004-Mar-25, 03:20 AM
Unless I'm seeing things, where the dust was cleared off of the "Mazatzal" rock, spirit has found a big chunk of ice?? Look at these microscopic pictures and let me know that I'm not nuts (in this case at least :D )
http://marsrover.nasa.gov/gallery/all/spirit_m079.html

CrzyWeazl
2004-Mar-25, 03:22 AM
Plus, if you look near the top, that has to be Han Solo frozen in there!!!!
LINK (http://marsrover.nasa.gov/gallery/all/2/m/079/2M133386527EFF2232P2977M2M1.JPG)

Squink
2004-Mar-25, 05:52 AM
That looks a lot like a big ole hunk of ice.
I hope NASA will take the time to powder some of it up and construct the first martian snowman for us. :D

Squink
2004-Mar-26, 10:47 PM
Nav cam shot of Mazatzal (http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20040322a/x_pubeng_mazatzal_nav-A078R1_br.jpg)

Here's a few links discussing ice at Gusev:
[NOT announcements that Spirit found ice. I expect NASA will let us know if and when they're certain. They haven't said anything yet]

www.cosis.net/abstracts/EGU04/03072/EGU04-A-03072.pdf+spirit+gusev+ice&hl=en&ie=UTF-8]Scenarios (http://216.239.53.104/search?q=cache:zvPE0A1BTBoJ: (abstract only)

www.lpi.usra.edu/meetings/lpsc2004/pdf/2164.pdf+spirit+gusev+ice&hl=en&ie=UTF-8]Spirit (http://216.239.53.104/search?q=cache:dTxk_EiHjHsJ:[url) at Gusev Crater: Preliminary Observations, Potential Processes and Hypotheses.

Earth, Wind and Fire: What's Missing? (http://mars.astrobio.net/news/print.php?sid=210)

johnwitts
2004-Mar-26, 10:59 PM
That looks like ice to me, or at least something transparent. They did say in Bethany Ehlmann's press briefing that they found the rock harder than expected and were going to have another grind tomorrow to get a record depth of 8mm. Could a chunk of ice survive on Mars?

somerandomguy
2004-Mar-26, 11:45 PM
If it's ice, is there any way to know whether it's water ice or CO2?

Squink
2004-Mar-27, 01:21 AM
If it's ice, is there any way to know whether it's water ice or CO2? The afternoon temperature at Gusev is running at about -11C (http://www.news.cornell.edu/releases/Jan04/MarsTemps.bpf.html), which is too warm for solid carbon dioxide.
From another abstract (http://216.239.41.104/search?q=cache:OyVqZCvrvV4J:ifp.uni-muenster.de/spp1115/content/kolloq03/Abstracts/Helbert_Benkhoff.pdf+J.+Helbert+%22Optical+Informa tion%22&hl=en&ie=UTF-8):
While recent results from the GRS instrument on Mars Odyssey indicate that Isidis Planitia shows only small hydrogen abundances in the soil, the region around Gusev Crater shows an enrichment of hydrogen, possibly indicating ground ice deposits
within the upper 2m below the surface. This is in agreement with our modeling results. For the landing sites in the Isidis Planitia region we derived a minimal burial depth of at least 5 m. For Gusev Crater however the results indicate ground ice deposits relatively close to the surface which can be stable over long time periods.

CrzyWeazl
2004-Mar-27, 06:34 AM
I was under the impression that ice would sublimate at the mars ambient pressure?? If this is ice, and it sure looks like it, it has been around a looooooong time, and does not look like its undergone any sublimation.

johnwitts
2004-Mar-27, 09:43 AM
If it's had a coating of some sort, then this could account for there being no sublimation. Also, a coating would shield the ice from the sun, keeping it from being exposed to direct heating from solar radiation. If the rock disappears over the next few days, we should get our biggest clue. :)

Squink
2004-Mar-27, 06:41 PM
From today's press release:
The rock abrasion tool operated on the New York target for three hours and forty-five minutes and created an impression in the rock that was 3.79 millimeters (.15 inches) deep. The angular shape of Mazatzal and the fact that the rock is a little harder than previously abraded rocks allowed the more flat side of the circular target to receive a more intense grind.
Diamond, that's it. It must be space-diamond! :^o

themusk
2004-Mar-28, 02:35 AM
From today's press release:
The rock abrasion tool operated on the New York target for three hours and forty-five minutes and created an impression in the rock that was 3.79 millimeters (.15 inches) deep.<snip>
Diamond, that's it. It must be space-diamond! :^o

Unless, of course, those were merely 225 New York minutes...

CrzyWeazl
2004-Mar-28, 10:25 PM
Appears to have air bubbles in it as well... They HAVE to announce something on this!

http://marsrover.nasa.gov/gallery/all/spirit_m082.html

johnwitts
2004-Mar-29, 12:51 AM
Sorry to burst everyone's bubble ( :) ), but could it be some kind of glass? If there's been an impact here, with tremendous heat, couldn't a chunk of glass have been made?

CrzyWeazl
2004-Mar-29, 12:56 AM
Party pooper

Squink
2004-Mar-29, 02:03 AM
Sorry to burst everyone's bubble ( :) ), but could it be some kind of glass? If there's been an impact here, with tremendous heat, couldn't a chunk of glass have been made? I don't see any glassy looking chips in (or around) the ground surface (http://marsrover.nasa.gov/gallery/all/2/m/082/2M133648391EFF2232P2959M2M1.HTML). It'd have to be a pretty uniform glass, which is belied by the differences between the left and right side of the photo. And what's up with the bumpiness on the left side? The Rat's cutting head (http://www.honeybeerobotics.com/rat.html) employs 125-150 micron (about 100grit) diamond abrasive. On a glass it should give a smooth, or at least uniformly scratched surface. Now if the 3000 rpm tool were causing a bit of local melting, you'd get a fouled grinding tool, a slow grind, and a bumpy surface.

iFire
2004-Mar-29, 02:03 AM
Maybe its the feces of Hoagland's glass worm... :wink:...

RGClark
2004-Mar-29, 03:42 AM
Sorry to burst everyone's bubble ( :) ), but could it be some kind of glass? If there's been an impact here, with tremendous heat, couldn't a chunk of glass have been made?

Here's a 3D image of the area:

http://tourlaville.nerim.net/2M133386588EFF2232P2957M2M1_3Dredcyan.jpg


Bob Clark

Amadeus
2004-Mar-29, 10:47 AM
If it was ice, then would not the heat from the friction of grinding melt the ice?

I was thinking volcanic glass myself.....
Anyone know if they've put to spectromitor on in? That should tell us what it is.

JonClarke
2004-Mar-29, 11:42 AM
Just looks like fine-grained basalt to me.

Jon

EFossa
2004-Mar-29, 12:05 PM
Just looks like fine-grained basalt to me.

Jon

Yep looks like more boring basalt, how long have we been stuck infront of this rock? seems like forever. The need to start heading off to the hills. :D

RGClark
2004-Mar-29, 04:44 PM
Just looks like fine-grained basalt to me.

Jon

Take a look at this 3D version:


Use red/blue glasses:

http://tourlaville.nerim.net/2M133386588EFF2232P2957M2M1_3Dredcyan.jpg

It definitely gives the appearance of transparency. Standard basalt is not transparent. Certains types can be, particularly when quenched by liquid water.


Bob Clark

JonClarke
2004-Mar-29, 10:01 PM
Still looks like fine-gained basalt Bob. Ice would be much more reflective, show up clearly and immediately in the SWIR spectrum. Do you really think the edge of a crater on the equator is the place to find exposed blocks of ice?

Jon

CrzyWeazl
2004-Mar-30, 02:06 AM
How does this not look reflective??

http://marsrover.nasa.gov/gallery/all/2/m/082/2M133648391EFF2232P2959M2M1.JPG

This is the equator of MARS, we are not talking about central africa here lol.

JonClarke
2004-Mar-30, 09:30 AM
The cleaned area is very poorly reflective, consistent with basalt. It appears featureless, consitent with fine-grained basalt. It's surface is slightly fluted but otherwise very smooth, consistent with the intense sand blasting seen by almost every rock seen at Gusev.

Ice convwersely, if clean, would show either specular reflection of coarse and free of inclusions, or be white is clean and full of inclusions. if it were dirty it would be dull and have lost of inclusions. This rock shows none of these features.

Ice is not stable at the martian equator in long term within a metre or two of the surface. the air pressure is too low and the temperature too high 9even though on average still below freezing, surface temperatures locally rise above melting and the ice would rapidly sublime or melt and evaporate. That is why there is none in the MO GRS data. Any ice found would have to be exposed recently. The rock in question is on the rim of a crater, its exposure must date from the time of crater formation. the crater is heavily eroded by wind and largely filled in. On Mars this points to an age of millions of years.

All the evidence points towards this feature being a rock and away from it being ice.

Jon

RGClark
2004-Mar-30, 04:24 PM
The cleaned area is very poorly reflective, consistent with basalt. It appears featureless, consitent with fine-grained basalt. It's surface is slightly fluted but otherwise very smooth, consistent with the intense sand blasting seen by almost every rock seen at Gusev.

Ice convwersely, if clean, would show either specular reflection of coarse and free of inclusions, or be white is clean and full of inclusions. if it were dirty it would be dull and have lost of inclusions. This rock shows none of these features.

Ice is not stable at the martian equator in long term within a metre or two of the surface. the air pressure is too low and the temperature too high 9even though on average still below freezing, surface temperatures locally rise above melting and the ice would rapidly sublime or melt and evaporate. That is why there is none in the MO GRS data. Any ice found would have to be exposed recently. The rock in question is on the rim of a crater, its exposure must date from the time of crater formation. the crater is heavily eroded by wind and largely filled in. On Mars this points to an age of millions of years.

All the evidence points towards this feature being a rock and away from it being ice.

Jon

I was suggesting it could be one of the glassy forms of volcanic rock that form on cooling with contact with liquid water:

Vic Camp - interaction of lava and water
http://www.geology.sdsu.edu/how_volcanoes_work/lava_water.html

Here's an image:

http://www.geology.sdsu.edu/how_volcanoes_work/Images/Hydrovolcanic/hyaloclastite_l.jpg

In regards to ice, the GRS spectrometer showed both Gusev and Meridiani to be equatorial sites with substantial amounts of subsurface water.
These images however, are just millimeters subsurface, and I would expect such ice to be several centimeters to a meter subsurface according to the GRS readings.


Bob Clark

JonClarke
2004-Mar-30, 09:56 PM
Glass certainly form when basalt interacts with water, however it s normally associated with hydrotehrmal alteration and hyalocastic brecciation. texturally there is not sign of the second, although this does not prove it does not happen.

Certainly the rock has had some kind of interaction with volatiles. There is a vein cutting acorss the rock, filled with pale material (zeolites? clay?, sulphate? carbonate? quartz?), there are also irregulatr pale pacthes that might be vesicules filled by similar material. This could be a point to water in the environment when the rock erupted, or simply a volatile rich magma.

Jon

Squink
2004-Apr-02, 01:59 AM
It's not ice (http://www.badastronomy.com/phpBB/viewtopic.php?t=12542&sid=2a8c337585f47418d509ab86 d3f04ab7).