Mars Ice Deposit Holds as Much Water as Lake Superior | Hacker News Reader

Mars Ice Deposit Holds as Much Water as Lake Superior

jpl.nasa.gov

362 pointsazazqadir77 comments

Lake Superior has enough water to flood all of North and South America to almost one foot.

Was intrigued by this comment so I looked it up.

North and South America have a surface area of about 42.55 million sq km or 4.58x10^14 sq ft (1 foot deep water is obviously 4.58x10^14 cubic feet).

Lake Superior has a volume of 12,100 cubic km or 4.2x10^14 cubic feet.

That's unbelievable!

now do the calculations on lake baikal.

About 8.12x10^14 cubic feet, so about 1.77 feet spread over all of the Americas.

What about Guarani Aquifer?

A little over 3 feet.

http://www.wolframalpha.com/input/?i=(40,000+cubic+kilometre...

To skip ahead, the Great Artesian Basin, the largest artesian basin in the world, would be just over 5 feet.

http://www.wolframalpha.com/input/?i=(64,900+cubic+kilometre...

https://en.wikipedia.org/wiki/Great_Artesian_Basin

How much fracking liquid could we pump in there and remain profitable?

You're pumping in what's (loosely) soapy water to extract water. And in places where there's mostly positive pressure anyway.

None?

I like that Wolfram Alpha will just do this one for you:

http://www.wolframalpha.com/input/?i=volume+of+lake+superior...

It struggles with the more esoteric aquifers, and doesn't understand "North and South America" as an object, but still pretty cool.

But according to Wikipedia, Lake Superior has an average depth of 483 ft.

So take the area of the lake and multiply it by 483, and now it is not surprising that you can cover North+South America with it.

I read the post title and thought "huh that's all?". Then I read your comment!

Also puts into perspective just how much water there is on earth.

Here is another way to put it into perspective[0]: http://water.usgs.gov/edu/pictures/full-size/global-water-vo...

[0] - http://water.usgs.gov/edu/earthhowmuch.html

Exactly the same here. Love it when something that is simply too large for comprehension is reframed in an easy to understand way.

That lake is not just huge, but crazy deep. It's bigger than the state of Maine in terms of area and in places is deeper than the Empire State Building is tall.

Or in other words, imagine turning Maine into a fishtank forty stories high that's full of fresh water.

Yet another perspective: From http://water.usgs.gov/edu/wateruse-total.html in 2010 306 billion gallons of fresh water per day used in the united states. Volume of Lake Superior is very roughly 3,000,000,000,000,000 gallons.

V Lake Superior / (306 * 10^12 * 365) = 26.86 years

About 27 years of entire US water supply assuming no water cycle. Now that I do the math (hopefully I didn't screw it up), I'm not sure that's a big number or a small one actually.

Its big... take in account the inefficient water management that we have and that a martian colony would be numbered in the thousands, at best. This is basically unlimited reserves!

Really puts into perspective how much water is in the great lakes!

Or... cover the surface of mars with ~ 3 inches (8 cm) of water.

Water behaves very strangely on Mars. http://www2.cnrs.fr/en/2753.htm -- Note the videos.

Interesting that this is in the "Utopia Planitia." That is starting to look like a probable location to set up a colony.

Mars is still less habitable than the Earth would be post nuclear war.

If we could just pack up some of this extra CO2 & get it over there, maybe we'd have a new planet! I wonder how many PPM you'd need?

Yeah, but how are we going to reheat and spin up the core?

Can't we just let the market handle that?

Very funny.

Have you tried turning it off and on again

/ducks to avoid projectiles

I've progressed to the eternal struggle between pounding on it with my fist and utter apathy.

Apathy is on its way to winning.

(Don't tell Jen.)

Hmm. Downvotes.

Isn't this the next step after turning it off and on again.

Back when we had more mechanical drives, daughterboards, socketed chips and the like, it worked a surprising amount of the time.

Apathy... Maybe that comes with age.

P.S. Not to mention tubes. Yeah, I'm that old.

P.P.S The grandparent was making a reference to a show, and Jen is a character in that show. In case that was confusing anyone.

Clearly, by drilling to it in a ship carrying several nuclear devices.

http://www.imdb.com/title/tt0298814/

Why do we need that?

Because a magnetic shield will prevent the solar winds from wiping your atmosphere.

Without a spinning core, Earth would be like Mars.

Of course you can live in caves instead of trying to terraform Mars, but doesn't sound so fun.

If we had the ability to terraform Mars wouldn't we just terraform Earth?

If you want to terraform Mars, it's probably not because you decided Earth was beyond salvation; I haven't heard many people wanting to abandon Earth. Most people in favor of terraforming Mars want to have a 'backup' for intelligent life, or want to begin humanity's expansion past the bounds of Earth's atmosphere. The 'backup' motive is comparable to suggesting someone backup their electronic data instead of just trying to get very reliable drives.

I am also not sure that it is possible to 'terraform' Earth. 'Terraform' means 'to make like Earth', and Earth is as Earth-like as is possible, no matter how hot or cold it is.

Humans have been terraforming Earth for at least the last hundred years (industrial scale) to 10,000+ years (agriculture, livestock, extinction of other species).

...because we don't need to? Earth is already full of plant life. Mars isn't.

Sorry for the overly blunt answer, because I know this isn't the question you're asking, but IMHO the question you're asking is based on a ridiculous premise.

We are polluting the Earth. Yeah, this is really bad for the Earth, and for us, but it isn't going to kill all life here. The thing that a "backup planet" is here to protect against is something like being struck by a meteor, or a plague, or nuclear war. Something where everybody dies very quickly, not something where life changes radically.

Solar wind strips that atmosphere very slowly over geological timescales. If we terraform Mars, then we probably have the technology to replenish it faster than that loss.

Geomagnetism also keeps your genetic change (via irradiation) from exceeding your tolerance. Relevant within single and generational lifespans.

I.e. Breathing is of limited utility, if the solar weather still gives you cancer.

Without a magnetic field, there is way too much radiation on the surface of Mars. A colony would pretty much need to live underground. If you are going to live underground on a planet with unusably-thin air, why not live on the Moon instead?

Instead of just asking the question that many people think they have answered, why not say what you don't like about their answers?

For example, Elon's speech about Mars colonization gives one answer. Maybe you've got great reasons to disagree with him. Maybe there's someone else you'd like to reply to?

(Hint: folks advocating for Mars think the atmosphere is not unusable.)

Not quite sure what you mean: I was responding to a question asking why it would be nice to have a liquid core. In other words, I was commenting on the radiation question.

To hide from Radiation, one plan is to have 16 feet of soil on top of the habitat [1], and limit outdoor time to just 2 hours a day. Given those levels, I'd argue that it would make better sense to build entirely underground on the Moon. The Moon has a shallower gravity well, much stronger solar flux for power, and is much closer for resupply.

[1] http://www.space.com/21813-mars-one-colony-space-radiation.h...

Surprisingly, a microwave oven satisfies both requirements

Yeah but it always makes the crust soggy.

Maybe we can get one of those foil crisper trays that microwave pizzas come with, stick it behind Mars.

Mars is 96% CO2, I think it might already have enough. In fact, the problem is trying to get rid of it all.

Mars has almost no atmosphere, being almost entirely composed of CO2 is the least of it's problems.

Good spot to land the Spacex's ITV.

There are places on Mars where water ice is available year-round, and carbon dioxide ice seasonally, at high latitudes. Therefore, I'd say this discovery, at low latitudes, has few implications for colonization unless there's a fair bit of carbon dioxide ice mixed in. So I'm waiting for word on that before getting too excited.

The entire core of Mars is made out of ice. The reactor melts it, and it makes air.

Why this excellent movie reference is down voted, I know not.

God, I hope one day the act of regurgitating the script from a vaguely relevant, fictional work is no longer celebrated.

Total Recall kicks ass

King of Mars. Called it.

Or mud, as this stuff otherwise known.

Given the temperature and pressure of Mars' atmosphere, "permafrost" might be a better comparison.

There is a sentence that seems to imply that the frozen status implies there is no life. I'm not so sure we can be sure of that. There are microbes on Earth that basically live in virtually frozen environments. (All you need are moments when the water is liquid.)

You could even just have life that moves more slowly because of the lower available energies. If we ever find some life that does not have an Earth origin perhaps we can finally get some more data points about what environments are really required for life.

All you need are moments when the water is liquid.

But you don't get those at such low atmospheric pressure. Mars atmospheric pressure is around 600pa. Below 611pa, the boiling point of water drops to the freezing point; you can have ice or steam, but not liquid water.

But you don't get those at such low atmospheric pressure. Mars atmospheric pressure is around 600pa.

A mental exercise: Any place on Mars with higher than 600pa pressure?

https://en.wikipedia.org/wiki/Hellas_Planitia

How about underground? How about the bottom of a glacier? No need to be "surfacist." ;)

An unsealed hole underground would have to be dug to the same depths as that crater. If you're pressurizing it, you'll probably target 1 bar to live in it, instead of 600 KPa.

A glacier that has the pressure to melt ice, would have more than enough pressure to keep it from sublimating. A rough estimate says that a foot or so of ice could provide over 600KPa of pressure, but that doesn't account for any means of keeping the water liquid or the ice solid. However, I wouldn't expect to actually find that on Mars. You might be able to keep water that way for a while until it froze again.

They do have recent satellite images that appear to show signs of water running down ravines at certain times of the Mara year. Don't have a citation handy, though.

That explanation is sublime.

You're going to be hard pressed to out pedantic NASA scientists. They probably spent quite some time deliberating over the term "Ice Deposit" as the most accurate one.

you're this smug about an article describing a huge water deposit on mars? I'd hate to get your opinion on something more mundane

It is not mud. Firstly it is not liquid, it's frozen. Secondly, it's not permafrost where it's mixed with a considerable amount of dirt, it's ice, a sub-surface glacier, one of many on Mars, merely the largest one we've discovered so far.

Which is about a millionth of the total water on Earth.

From TFA: "It represents less than one percent of all known water ice on Mars..."

Now I think it's a good idea to colonize the place.

This should be enough for a colony though. With a recycling program it would probably last indefinitely. Much better than bringing the water from Earth.

Just bring the right kind of people and God will flood it.

You actually made me laugh. I immediately thought of Trump. With global warming and his disbelief in it I think we are heading unto our own flood.

Just the two little problems with the magnetic field and atmosphere left to solve.

Recyling could mean never letting it out into the atmosphere in the first place. Or maybe would, since there is no water cycle to talk of on Mars. Think closed-loop aquaponics systems etc.

I mean that water if going to be the least of your problems, unless you've mastered terraforming (we haven't) or you're okay with living under a huge dome (that we don't even have technology to build, either). Liquid water cannot exist on Mars, and liquid blood can't either, so you would die horribly if you went on Martian sole without a spacesuit. Apart from having gravity, living on Mars would be like living on the ISS, minus the food they bring to the station from Earth...

Yeah, Mars. We're not impressed. It's just a muddy frozen lake, not an ocean. Total crap idea. Also, your web design sucks.

Your comment is of really low quality.

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