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Water Ice On Mars
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.
Now we just need a little global warming.
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.
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?
Everything will be taken away from you.
http://science.slashdot.org/article.pl?sid=08/06/20/026241
First against the wall when the revolution comes
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".
Admit it. You post strawman arguments as AC so you get modded Insightful for refuting them, rather than Troll
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, where you can actually see the small chunks farther down disappearing completely.
It means we finally have a suitable accompaniment for Martian scotch.
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.
A learning experience is one of those things that say, 'You know that thing you just did? Don't do that.' - D. Adams
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.
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.
"It's too bad that stupidity isn't painful." - Anton LaVey
Could we have this important information in units used by, I don't know, the rest of the world?
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"
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.
Well, back to rejecting software patent applications.
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.
Mod me down with all of your hatred and your journey towards the dark side will be complete!
News fails to take responsibility according to one internet poster.
More at 8.
Well, back to rejecting software patent applications.
Not only that, but Phoenix has a little weather station on board called the Telltale project. And if you look at this page 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.
http://www.rootstrikers.org/
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
http://www.solarviews.com/cap/mars/frost.htm
That frost sublimated just like this ice did.
Here are other observations:
http://science.nasa.gov/headlines/y2002/28may_marsice.htm
Here you can see a frozen crater lake:
http://esamultimedia.esa.int/images/marsexpress/210-010705-1343-6-co-01-CraterIce_H.jpg
http://www.esa.int/SPECIALS/Mars_Express/SEMGKA808BE_0.html
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.
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!
This space available.
Do it yourself, because no one else will do it yourself. [beta blockade 10-17 Feb]
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 ... :)
The little guy just ain't getting it, is he?
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.
don't cut it off www.mgmbill.org
Yep, Vodka.
Here
How to read them
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.
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
There's a perfect xkcd for my sig but I'm too lazy to look it up. sudo someone go find it.
> Hopefully they are right about it.
Of course they're right about it, they have solid photographic evidence.
A similar experiment was recently conducted to determine the existence of life in Congress. A large pile of money was left sitting out which sublimated while votes accreted; thereby proving the existence of life in Congress. It is still up for debate how long before intelligent life is found in Congress.
A couple of 30-somethings embark on the ultimate roadtrip
So these two frames were taken four days apart while the sublimation was taking place. My question would be - where are the rest of the frames? Does this lander really only "look around" every few days?
It would be nice to see it at even a 1-day resolution and get a 4-frame animation of the process. Those lumps should be seen to get smaller and vanish.
Not that I'm complaining, this is still very cool (no pun intended).
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
Yes, still not cold enough as far as I can tell given this phase diagram and these temperatures and pressures.
Were that I say, pancakes?
U.S needs to upgrade it's standards. A good start would to move from Fahrenheit to Celsius. After that you can move over to the metric system.
-70 F is -56 C
-109 F is -78 C
Conversion done with Google.
The AC is thinking critically, while you appeal to authority. Which type gets to work at NASA?
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
You'd hope that after 300 or so years of chemistry we'd understand how to recognize water...
there's a number of geological processes that can concentrate water like this
in areas on earth where a lot of freezing and thawing occurs on earth, rocks get concentrated neatly in rings according to size, as if someone sorted them
i'm not saying this process is anything like why the ice is so pure on mars, what i am saying is that there are plenty of natural processes out there that concentrate materials in orders that, contraintuitively, seem like it took intelligent concentration, but are in fact totally natural
i won't even begin to speculate what processes on mars could do this, but i wouldn't be surprised if someone more knowledgeable than me could describe such a natural mechanism for ice purification on mars
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Neither, because NASA only hires smart people.
If you mod me Overrated, you are admitting that you have no penis.
I thought this Wired quote about why the water sublimates on Mars is interesting:
"Just like dry ice does here on Earth, water ice goes from solid to gas when the pressure is below 6.1 millibars and it gets heated (like it does in the Martian sun). It can also go straight from solid to gas above 6.1 millibars when the vapor pressure (amount of water vapor in the air) is low enough. This is because the molecules of water in solid form and gas form are not at equilibrium."
http://blog.wired.com/wiredscience/2008/06/answering-mars.html
ZuluPad, the wiki notepad on crack
There is a fair bit of difference between believing and knowing!
You're right. Definitely photoshopped.
Truth arises more readily from error than from confusion. -Francis Bacon
It took many days to determine that the white stuff Phoenix uncovered was ice (and not salt). An astronaut on Mars would have made that determination within seconds.
A-Bomb
First, there are asteroids that are pure (or near pure) ammonia. Second, the CFCs are nice, but the ammonia is cheaper and useful afterwards. In particular, the Ammonia starts off as greenhouse gas and then breaks down into pure N2, which then becomes a buffer gas. With CFCs, we would have to import or mine it. As to the water, well, you break up the asteroid just as you hit the atmosphere. Never impacts.
I prefer the "u" in honour as it seems to be missing these days.
After looking at that fascinating GIF from the summary, I'm not sure it is water. It just kind of disappears. It's probably some sort of highly advanced life form that can change its shape at will and lives beneath the planet's surface most of the time. It then just came up for a little Martian sunshine and, upon noticing our probe went back to tell its buddies that the Earthlings sent more crap to their planet and that they should expect an invasion soon. Unless they can prove to us they don't have any oil.
Well, that's what it looks like to me. Draw your own conclusions.
Saying "I'll probably get modded down for this" in a post is the best way to get it modded up.