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Water Ice On Mars

kdawson posted more than 5 years ago | from the not-wet dept.

Mars 364

cathector sends along a story from SpaceWeather.com on the discovery of water ice on Mars. "Scientists have figured out the mysterious white substance unearthed by NASA's Phoenix lander on Mars. It's frozen water. The breakthrough came last week when Phoenix's stereo camera caught the substance in the act of disappearing. Bathed in martian sunlight for four days, the white substance sublimated — i.e., it transformed from solid to gas without passing through the liquid state. This is how water behaves on Mars.... Some readers have asked, how do we know the white substance is not frozen CO2 (dry ice) instead of frozen water? Answer: Phoenix's landing site is too warm for dry ice. The average daily temperature is about -70 F while dry ice requires temperatures lower than about -109 F." The animated GIF showing the ice sublimating is pretty nice too.

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364 comments

Wow (0)

suso (153703) | more than 5 years ago | (#23897987)

This is actually pretty exciting news. Hopefully they are right about it.

Re:Wow (4, Funny)

thermian (1267986) | more than 5 years ago | (#23898089)

You're absolutelly right, all we need now is some Martian Whisky and the social lives of any future human expedition is well and truly sorted out.

Re:Wow (1, Funny)

Anonymous Coward | more than 5 years ago | (#23898347)

In fact, forget the social lives of any future human expedition!

Wind? (0, Interesting)

Anonymous Coward | more than 5 years ago | (#23898007)

How do we know wind didn't blow stuff away?

Re:Wind? (5, Informative)

Mr2cents (323101) | more than 5 years ago | (#23898099)

It was at the bottom of a trench. Plus, wind doesn't selecticely blow white rocks away while letting the rest of the scene untouched. Plus, you can also see some white areas at the end of the trench getting smaller.

It's ice. Definitely.

Re:Wind? (4, Informative)

Concerned Onlooker (473481) | more than 5 years ago | (#23898257)

Not only that, but Phoenix has a little weather station on board called the Telltale project [marslab.dk]. And if you look at this page [space.gc.ca] you can see the weather reports for where Phoenix is on a sol by sol basis. None of them show windy conditions, although it looks like there is data missing for a few sols.

Re:Wind? (2, Insightful)

Anonymous Coward | more than 5 years ago | (#23898329)

True, wind doesn't selectively blow white rocks.

But it would selectively blow an ultrafine powder which happened to be white.

Re:Wind? (4, Insightful)

Jafafa Hots (580169) | more than 5 years ago | (#23898521)

OK, we admit it - none of the NASA scientists are as smart as you are, the whole "powder" thing just never occurred to them. Doh!

Re:Wind? (4, Funny)

mrbluze (1034940) | more than 5 years ago | (#23898525)

But it would selectively blow an ultrafine powder which happened to be white.
Surely the wind would be better off snorting it?

Re:Wind? (-1, Troll)

Anonymous Coward | more than 5 years ago | (#23898583)

Those 'white' areas could be some of the coating on the underside of the scoop was transferred onto the soil.

As for the photos...they were supposedly taken days apart, yet they are identical except for missing some chunks...while half the shadows moved and half didn't. Photoshopped if you ask me.

It's called the 'Phoenix' lander because it landed just outside Phoenix...

POOL PARTY!!!! (3, Funny)

Anonymous Coward | more than 5 years ago | (#23898015)

Now we just need a little global warming.

Stupid terraforming.. (1)

tjstork (137384) | more than 5 years ago | (#23898029)

So, if we sent a bunch of robot tractors to Mars and uncovered the dirty ice caps, wouldn't they all sublimate and all that water vapor would warm the planet? Are we looking at a cheap way to terraform the planet?

Re:Stupid terraforming.. (1)

Narcocide (102829) | more than 5 years ago | (#23898093)

I am not a scientist, but assuming that the water they just found is actually water, and that there is enough of it, that would work I think.

"Cheap" however I don't think is the correct word to use for this type of a project.

Re:Stupid terraforming.. (2, Funny)

Aphoxema (1088507) | more than 5 years ago | (#23898515)

We could always just ship the abundance of water we have to Mars. Oh, wait, that's 10 years from now when politicians can't deny global warming any longer and they'll need some other boneheaded assumption to go on like water not being all that heavy to launch into space. The shit practically lifts itself!

Re:Stupid terraforming.. (4, Informative)

CDMA_Demo (841347) | more than 5 years ago | (#23898105)

escape velocity on mars is 5.027 km/s, and water vapor will slowly move out of mars because of its high rms velocity. So, the answer is "no"

Re:Stupid terraforming.. (3, Interesting)

Bob(TM) (104510) | more than 5 years ago | (#23898621)

Actually, that argument can be made for any atmospheric gas constituent, not just water vapor.

There is less water in the Martian atmosphere oxygen while the water is more massive, so the oxygen would leave at a proportionally greater rate (assuming we are observing a long term steady state). One theory of the rapid loss has more to do with disassociation of H and O by UV radiation. H would quickly leave by your molecular motion argument leaving a relatively larger amount of O.

If that's the case, we'd be much better off leaving it subsurface for life sustaining purposes - sublimed ice is lost water. Now, we could use a bunch of nukes to lift dust to the increase greenhouse effect ... :)

$3,000,000 mint juleps at next year's derby (4, Funny)

ecklesweb (713901) | more than 5 years ago | (#23898037)

In other news, NASA announced today that a manned mission to Mars is planned to retreive the newly found ice in time for the 2012 Kentucky Derby. NASA plans to upstage Woodford Reserve's famous $1000 Mint Julep at the race with its own $3,000,000 version of the traditional cocktail. While plans are still being firmed up, the beverage will reportedly come in a limited edition collector's glass.

Re:$3,000,000 mint juleps at next year's derby (0)

Anonymous Coward | more than 5 years ago | (#23898213)

That would be like eating yellow snow, except that it's red Martian pee.

Snow (4, Interesting)

Joe Tie. (567096) | more than 5 years ago | (#23898043)

Pardon my total ignorance of the subject, but does this mean that it might occasionally snow on mars? Or would the environment be too different to allow it?

Re:Snow (5, Interesting)

Mr2cents (323101) | more than 5 years ago | (#23898197)

No, martian air is way too dry to form snow. There is water in the athmosphere, but IIRC it is something like a layer 1mm thick if all the water would condense on the ground. What happens is that some of that water freezes to/in the ground if it gets cold enough.

What I learned from following the press conferences online, is that since mars doesn't have a large moon, the axis of rotation changes much more than earth does, so if it is directed towards the sun, the ice could actually melt.

Re:Snow (4, Interesting)

MichaelSmith (789609) | more than 5 years ago | (#23898227)

Pardon my total ignorance of the subject, but does this mean that it might occasionally snow on mars? Or would the environment be too different to allow it?
The area the lander in is covered by ice during the winter so we are going to find the answer to your question quite soon.

Water sublimating (4, Interesting)

NoobixCube (1133473) | more than 5 years ago | (#23898053)

If I remember my chemistry classes correctly (there is a high chance I don't), water would do this under lower air pressure, I think. Correct me if I'm wrong, I just thought some kind of explanation would be better than "because it's on Mars".

Re:Water sublimating (4, Interesting)

Rob Kaper (5960) | more than 5 years ago | (#23898111)

Is water the only material that can sublimate? If not, why should we be so sure this has to be water just because we want it to be?

Re:Water sublimating (2, Informative)

jberryman (1175517) | more than 5 years ago | (#23898189)

CO2 sublimes on earth of course, and many other substances do under different conditions. Per the summary, we know it could not be frozen CO2.

Re:Water sublimating (1)

Tubal-Cain (1289912) | more than 5 years ago | (#23898211)

No, CO2 (dry ice) sublimates, too (among other things, such as probably most gasses). But if you read the summary notes:

Some readers have asked, how do we know the white substance is not frozen CO2 (dry ice) instead of frozen water? Answer: Phoenix's landing site is too warm for dry ice. The average daily temperature is about -70 F while dry ice requires temperatures lower than about -109 F."

Re:Water sublimating (5, Insightful)

PieSquared (867490) | more than 5 years ago | (#23898339)

Pretty much anything can sublimate under the proper conditions. But when you say "a white solid that sublimates at -70 degrees F and martian surface pressure and is found in macroscopic quantities naturally" you narrow down the field quite a bit. In this case, to exactly one reasonable possibility.

I know (5, Funny)

Anonymous Coward | more than 5 years ago | (#23898635)

Pretty much anything can sublimate under the proper conditions. But when you say "a white solid that sublimates at -70 degrees F and martian surface pressure and is found in macroscopic quantities naturally" you narrow down the field quite a bit. In this case, to exactly one reasonable possibility.

Yep, Vodka.

Re:Water sublimating (4, Informative)

Breakfast Pants (323698) | more than 5 years ago | (#23898117)

Doesn't really need to be under low air pressure, if ice is in the presence of low vapor-pressure it will sublimate (see icecube tray in your freezer).

Re:Water sublimating (0)

Anonymous Coward | more than 5 years ago | (#23898651)

Something is wrong with the statement I am replying to. Can someone restate whatever it is the person said?

Re:Water sublimating (4, Informative)

cyklo (795952) | more than 5 years ago | (#23898133)

Indeed it does, and it's probably better explained using a triple point diagram:

http://www.chemistrydaily.com/chemistry/Image:Phase-diag.png [chemistrydaily.com]

On earth (at higher pressures), increasing temperature goes from the solid, to liquid, and then to gas phases (the triple-point in the middle is at zero degress celcius)

The lower atmospheric pressure on Mars (~1% of sea-level earth pressure) means that you go straight from solid to gas. In fact, the liquid part is actually impossible (IANAChemist) unless you increase the pressure sufficiently.

Re:Water sublimating (5, Informative)

cathector (972646) | more than 5 years ago | (#23898319)

water sublimation doesn't need to be exotic; it happens in your freezer all the time.
you know how ice cubes gradually lose their sharp edges and finally become just little puddle-shaped lumps in the bottom of the ice try ? that's sublimation too.

Re:Water sublimating (1)

Jafafa Hots (580169) | more than 5 years ago | (#23898541)

Because there's automatic defrost on Mars?

Seriously, ever see ice cubes shrink away in the freezer?

phase diagram (3, Informative)

daemonburrito (1026186) | more than 5 years ago | (#23898661)

Here [wikipedia.org]

How to read them [wikipedia.org]

I feel that a great disservice was done to a lot of us early on with a simplistic view of the usual three phases of matter.

And yes, you're right. That is part of the explanation.

Better picture (5, Informative)

Jade E. 2 (313290) | more than 5 years ago | (#23898055)

That animation is actually cut off. The main sublimation that was observed is below the frame of that picture. There's a better one here [arizona.edu], where you can actually see the small chunks farther down disappearing completely.

Martian ice is really big news, folks! (4, Funny)

commodoresloat (172735) | more than 5 years ago | (#23898069)

It means we finally have a suitable accompaniment for Martian scotch.

Re:Martian ice is really big news, folks! (5, Funny)

Anonymous Coward | more than 5 years ago | (#23898077)

Neat!

Sorry - it's a Scotch joke.

Re:Martian ice is really big news, folks! (1)

sconeu (64226) | more than 5 years ago | (#23898323)

How can it be neat, if you're going to put ice into it?

Re:Martian ice is really big news, folks! (1)

maxume (22995) | more than 5 years ago | (#23898481)

Your question is its own answer, the ice is not in it yet.

Re:Martian ice is really big news, folks! (3, Funny)

ScentCone (795499) | more than 5 years ago | (#23898259)

It means we finally have a suitable accompaniment for Martian scotch.

Please call it by its proper name, would you?

Martch.

This is a dumb question, but... (1)

SilentChris (452960) | more than 5 years ago | (#23898075)

A first glance, it doesn't look to me like ice "melting" any more than salt or some other finely-grained material blowing away (no, I'm not saying it's salt -- just something that could move). Is there no wind in that area or something?

Re:This is a dumb question, but... (2, Informative)

Anonymous Coward | more than 5 years ago | (#23898137)

There is wind, however it apparently didn't move anything else in the pictures. Also, the wind wouldn't be very strong since the atmosphere is so thin.

What about the pressure? (2, Interesting)

Anonymous Coward | more than 5 years ago | (#23898091)

dry ice requires temperatures lower than about -109 F.
But what about pressure? A look at the phase diagram [wikipedia.org] shows that carbon dioxide can be a solid (dry ice) at 25 C (room temperature), but at 10000 bar. I dunno what the pressure is on the surface of Mars, but temperature isn't the only thing that dictates if dry ice exists. Pressure is just as important. I doubt that Mars has that kind of pressure though.

And why are we using F? This is a science article, posted on a web site for nerds.

Re:What about the pressure? (3, Informative)

CaptainPatent (1087643) | more than 5 years ago | (#23898167)

I'm sure that quote was with regard to the conditions of Mars.

You are also correct to assume that Martian pressure is nowhere near what is required for room-temperature dry ice. In fact it's about 1% that of earth's atmosphere. More reading here. [wikipedia.org]

Re:What about the pressure? (0)

Anonymous Coward | more than 5 years ago | (#23898403)

Pressure is important, but if you know that you really ought to know that the temperature given for dry ice to sublimate would be either at local pressure on site or at standard earth pressure, and that in either case for dry ice to sublimate at a higher temperature then given would require pressures higher then the pressure needed for the given temperature of -109. And that the pressure on mars is higher then that on earth, meaning that the dry ice would sublimate at -109 degrees or *lower* in the ambient pressure. And for the record standard pressure on earth is about ONE bar, and on mars about 1% of the pressure on earth. As 6 or 7 orders of magnitude from 10k bars needed for dry ice to sublimate at room temperature.

Re:What about the pressure? - Other way around (1)

mkiwi (585287) | more than 5 years ago | (#23898629)

You are correct, except that we know the pressure on the surface of Mars is lower because of the thin atmosphere. Jupiter or Venus are better candidates for what you are describing.

Interesting press coverage of this. (4, Insightful)

Gavin Scott (15916) | more than 5 years ago | (#23898095)

I've noticed that almost all of the news headlines covering this are qualified statements like "Lander finds water on Mars, according to scientists". As if they're afraid to actually say something straightforward like "Water found on Mars" and they have to make it clear that they're just reporting what someone else is saying (with the implication that maybe they don't really believe it). At the same time they seem to have no problem with other headlines like "Celebrity Arrested Drunk" without the need to qualify it as "Celebrity Arrested Drunk According To Police" etc.

Maybe it's just me, but I mind it a bit irksome that so many big news outlets seem so detached from any sort of science reporting these days.

G.

Perhaps they're waiting for NASA to weigh in (2, Insightful)

cpu_fusion (705735) | more than 5 years ago | (#23898183)

Although I agree with you in principle, I think it might be due to the anticipation of NASA's announcement, which could do away with the "according to scientists [working on the project]" caveat.

Re:Interesting press coverage of this. (1)

murrdpirate (944127) | more than 5 years ago | (#23898287)

Yeah, it can be annoying, but I think it's necessary. Scientists can make mistakes, and we sure wouldn't want the press to report everything said by any scientist as definite truth.

I actually hear them say allegedly any time a celebrity is arrested. They probably wouldn't be sued if this didn't turn out to be ice, so at least they do it to be accurate.

Re:Interesting press coverage of this. (1)

Escogido (884359) | more than 5 years ago | (#23898423)

I've noticed that almost all of the news headlines covering this are qualified statements like "Lander finds water on Mars, according to scientists". As if they're afraid to actually say something straightforward like "Water found on Mars"
I think the reason is that the scientists technically have no proof it is actually water - what they have instead is a substance that looks like water, behaves like water and quacks like water. Whether it makes said something water, you be the judge.

On the other account, I totally agree - the media don't always seem so scrupulous in other areas :)

Re:Interesting press coverage of this. (1)

mikael (484) | more than 5 years ago | (#23898449)

First rule of research - When unable to verify the information yourself, always reference your sources - that way, you don't get blame if the information is wrong or biased.

Re:Interesting press coverage of this. (2, Funny)

Jafafa Hots (580169) | more than 5 years ago | (#23898559)

Well, those scientists, all they have are "theories," doncha know. You can't trust them. Their stories are always changing, unlike the Word of our Lord And Savior which has been true for millennia.

All hail Zeus.

average daily temperature (5, Insightful)

Swampash (1131503) | more than 5 years ago | (#23898103)

Could we have this important information in units used by, I don't know, the rest of the world?

Re:average daily temperature (0)

Overkill Nbuta (1035654) | more than 5 years ago | (#23898185)

Could we have this important information in units used by, I don't know, the rest of the world?

Library's of congress? Iv seen that used a lot recently.

Re:average daily temperature (2, Insightful)

Bill, Shooter of Bul (629286) | more than 5 years ago | (#23898447)

Well, as soon as a country from a part of that world, then you'll get your pronouncements to the public in metric. You have to remember that NASA is publicly funded. They need the public engaged in their discoveries, in order to maintain their funding. So, it only makes sense that they report their public findings to the media in units that average ( and the not so average members of congress) understand. I'm sure there are those a NASA that thinks they should be trying to convince the American public to use Metric, but technically that's NIST's job

Re:average daily temperature (1)

gatkinso (15975) | more than 5 years ago | (#23898477)

Last time they tried that the damn thing shut off its engines 100 feet... er meters... er feet... whichever one it was anyway, above the surface and crashed.

Re:average daily temperature (4, Funny)

belg4mit (152620) | more than 5 years ago | (#23898549)

Send your own fucking probe if you can't be bothered to subtract 32 and multiply by 4/9.

Re:average daily temperature (4, Funny)

drawfour (791912) | more than 5 years ago | (#23898631)

They would be better off sending their own fucking probe than subtracting 32 and multiplying by 4/9. I'm not sure what units those are, but certainly not Celsius.

Re:average daily temperature (-1, Troll)

Anonymous Coward | more than 5 years ago | (#23898557)

Don't you freaks have calculators?

Calculate your own conversion to attempt-by-the-French-to-regain-relevance-on-the-world-stage units.

Re:average daily temperature (0)

Anonymous Coward | more than 5 years ago | (#23898573)

As soon as any Mars landers from any other part of the world are ready to report it.

Something's not right (1, Insightful)

Anonymous Coward | more than 5 years ago | (#23898115)

I thought the lander was loaded with scientific equipment. None of it can detect water? The best they can do is take pictures?

But still... (1)

T3Tech (1306739) | more than 5 years ago | (#23898155)

Have they figured out what flavor it is and can they get it back here without it melting so I can sell it in my new Mars Water Ice stores!?!?

could be CO2? (0)

Anonymous Coward | more than 5 years ago | (#23898157)

"The average daily temperature is about -70 F while dry ice requires temperatures lower than about -109 F."

well, it was in the state of sublimating (melting) so I don't think that disqualifies CO2?

Re:could be CO2? (1)

belg4mit (152620) | more than 5 years ago | (#23898435)

No, as the point they're making is that it doesn't get cold enough for dry ice to form. If it did, Mars' atmosphere would snow out.

Re:could be CO2? (0)

Anonymous Coward | more than 5 years ago | (#23898607)

Martian surface temperatures vary from lows of about â'140 ÂC (-220 ÂF) during the polar winters to highs of up to 20 ÂC (68 ÂF) in summers.

Re:could be CO2? (1)

Vectronic (1221470) | more than 5 years ago | (#23898497)

Although it seems to be taken as fact now among many, I'm still not ruling it out that it may still be CO2 (or similar), although the little pit seems to only be a few inches deep, maybe the surface of mars can reflect enough of the sunlight to make a few inches deeper -109F (-78C ish) or maybe much more.

I'm not sure at what speed Mars is rotating unto itself as well as around the sun, but by the change in shadows, there was a lot that melted in what seems to be a fairly short period which could also explain the amount of tempurature difference within a few inches.

One Problem: (4, Informative)

grasshoppa (657393) | more than 5 years ago | (#23898171)

Here's the problem: We still don't know conclusively. Yes, we have observations which are highly suggestive, but we don't have a chemical composition of the substance, so we don't know for sure.

Science is a hard mistress; she demands proof before making such claims.

Re:One Problem: (0, Troll)

Aqua OS X (458522) | more than 5 years ago | (#23898253)

Yeah, but we know how the substance behaves, we have knowledge about the environmental conditions, etc. Knowing what we know, few substances are going to exhibit those characteristics in that environment.

Re:One Problem: (2, Insightful)

SetupWeasel (54062) | more than 5 years ago | (#23898581)

You know NASA has made a few major announcements that they have had to retract in the past few years. Remember the "river beds" that had no other possible origin? NASA later admitted that they were likely caused by the wind.

NASA doesn't let science get in the way of a good press release.

Re:One Problem: (1)

PieSquared (867490) | more than 5 years ago | (#23898425)

Correct, and further experiments will be undertaken to confirm that it is indeed water ice.

In the mean time, though, it's pretty safe to act under the assumption that there is indeed water on mars.

Re:One Problem: (1)

mikael (484) | more than 5 years ago | (#23898489)

Can't they perform spectral analysis on the material - whatever the emission lines of H2O are are? Surely the cameras have wavelength filters?

Re:One Problem: (1, Insightful)

Anonymous Coward | more than 5 years ago | (#23898567)

Isn't it sad though that we can tell the composition of object hundreds of lightyears away including detecting water but even with a lander right there on Mars we can't confirm water even when the lander is staring right at it? There's something not right about the whole mission. The rovers use RAT tools to expose the virgin surface of rock so we could tell the composition but we can't detect water with a lander designed specifically for that one thing. The landers were a staggering success but this mission feels a bit embarassing. Honestly with the instruments on board could they confirm water if they landed in a pond? They expose frost and which is halfway there and we'll be debating for months or years to come what it really was. Do we need shots of a Martian taking a bath or selling bottled water to confirm it? Still wouldn't confirm anything because martians might bath and drink liguid CO2. I can think of a hundred low tech tests to confirm water. NASA seriously dropped the ball on this one. Apparently the only real test involves getting material into a pencil lead sized hole. By that standard an ice cube couldn't be tested for water. Here's a fun fact. If there are only trace amounts at the surface and the act of exposing it to the air to collect it causes it to evaporate does that mean we can't test for it? How about a heating element on an arm with a gas chromatograph? Stick heating element in soil, heat soil, test escaping gases. Repeat as needed.

Science is ladyboy. (1)

BiggerIsBetter (682164) | more than 5 years ago | (#23898639)

Science is a hard mistress; she demands proof before making such claims.
I prefer to think of her as a harsh mistress rather than a hard mistress, thanks.

Um ...Dumb Question. (0)

Anonymous Coward | more than 5 years ago | (#23898209)

If this is water..and it is in ice form..

and.. according to Wiki.. Sublimation of an element or compound is a transition from the solid to gas phase with no intermediate liquid stage.

umm..I think I may be stupid here... but isn't the surface temperature -70f..

Water freezes at 32..... how did it SUBLIMATE?

Re:Um ...Dumb Question. (2, Informative)

Anonymous Coward | more than 5 years ago | (#23898269)

It's 1% of Earth's atmospheric pressure. At that point there is no water, only solid and gas. And the sublimation point is a lot lower because of the lower pressure. (Less pressure = less molecules keeping the other molecules tightly packed)

ice on Mars is nothing new (5, Insightful)

speedtux (1307149) | more than 5 years ago | (#23898263)

Finding water was one of the key goals of the Phoenix mission.

That is a bizarre statement. Large quantities of ice have been observed in numerous ways already. Even the Viking lander observed water frost directly in the 1970's:

http://en.wikipedia.org/wiki/Viking_2 [wikipedia.org]

http://www.solarviews.com/cap/mars/frost.htm [solarviews.com]

That frost sublimated just like this ice did.

Here are other observations:

http://science.nasa.gov/headlines/y2002/28may_marsice.htm [nasa.gov]

Here you can see a frozen crater lake:

http://esamultimedia.esa.int/images/marsexpress/210-010705-1343-6-co-01-CraterIce_H.jpg [esa.int]

http://www.esa.int/SPECIALS/Mars_Express/SEMGKA808BE_0.html [esa.int]

Not only is that ice, it may actually be an outflow.

What makes the results from Phoenix exciting is that the actual experiments that Phoenix is supposed to perform depend on having landed on ice. But finding ice somewhere on Mars is not a surprise.

Um...Question? (1)

PitDoggie (913758) | more than 5 years ago | (#23898295)

According to Wiki... Sublimation of an element or compound is a transition from the solid to gas phase with no intermediate liquid stage. if it is -70f on Mars and according to my little pea brain ice freezes at 32f. How did the sublimation happen?

Re:Um...Question? (1)

belg4mit (152620) | more than 5 years ago | (#23898413)

And here I thought the explanation of what sublimation was in the summary was superfluous.
Please see the phase diagram for H20. Martian atmospheric pressure is extremely low.

Re:Um...Question? (1)

owlstead (636356) | more than 5 years ago | (#23898463)

First of all, no solid is entirely solid. At the atomic level there are always some particles moving around (a very thin layer of "liquid" molecules with a few gassy ones on top). So a bit of sublimation will probably always happen. Some "air" moving around will help.

But beside that, it's probably the light not heating up everything at the same pace.

Hundreds of millions spent and...? (1, Troll)

ThreeGigs (239452) | more than 5 years ago | (#23898361)

So, we spend a few hundred million to land something on Mars, a major part of whose mission was to confirm or debunk the existence of water there, and after 24 days all we can say is "Look, it's sublimated so it's probably water!"? I'm hearing jokes about Americans forgetting to include some simple 'test for water' equipment in their 325 million 'let's see if there's water on Mars' probe.

So, is anyone else thinking 'wtf?' like me? Why are we reduced to using pictures to try and determine if the stuff is water? Where the hell are the results of the conclusive tests so we don't have to use words like 'probably', 'most likely', and 'it shure looks like watuh, don' it?'.

Come on, NASA, you're making yourselves look incompetent.

Re:Hundreds of millions spent and...? (2, Funny)

drinkypoo (153816) | more than 5 years ago | (#23898531)

Come on, NASA, you're making yourselves look incompetent.

How much water have you found on Mars?

Uh-huh. I thought so...

Re:Hundreds of millions spent and...? (2, Interesting)

X0563511 (793323) | more than 5 years ago | (#23898561)

They haven't run the tests yet. This is just something they noticed when they landed.

We send this probe up there with all this fancy testing equipment, only to land in the friggin' stuff we're trying to find. It's actually pretty funny...

Life on Mars (1)

fyoder (857358) | more than 5 years ago | (#23898399)

The ice could be disappearing due to sublimation. Or it could be being consumed by a life form delighted to find a precious resource totally exposed and there for the taking.

Perhaps next mission they should take along some sugar. Put it out and see if it 'sublimates' as well.

Re:Life on Mars (4, Funny)

arb phd slp (1144717) | more than 5 years ago | (#23898669)

Perhaps next mission they should take along some sugar. Put it out and see if it 'sublimates' as well.

Memo to all Enforcers:
By order of the Council of Elders, anyone caught consuming the sweet, sweet bait near the robotic invader from the blue planet is to have his gelsacs summarily pierced.
Signed,
K'Breel

Sweeet (1)

EdIII (1114411) | more than 5 years ago | (#23898409)

Anybody else see Dan Quayle running around with his chest puffed up saying, "I Told You So".

Good for him :)

Biker Mice on Mars? (n/t) (0)

Anonymous Coward | more than 5 years ago | (#23898453)

n/t

How come the water is so white/clean? (4, Interesting)

viking80 (697716) | more than 5 years ago | (#23898627)

First, I think the best evidence so far that this is water is not this picture, but the fact that the Mars Orbiter's spectrometer determined that that is was a lot of hydrogen in the ground near the poles.

That some white stuff vanishes is poor evidence. They need to get the white stuff in an oven and test it.

Let's assume it is water.
What really puzzles me is how clean the water is. It is covered with what would make a dirty mud if it ever melted together. Also on earth, you never have clean water if you have flash floods like what you see as a result of a volcanic eruption or meteroid impact. You only have clean water/ice in snow and still lakes/oceans.
This implies:
1. The ice has not melted after the dust blew over it.(A long time)
2. It used to be a lake/ocean or snow

So the purity of the ice might be a bigger discovery than the fact that it is ice there.

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