Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Mars Ice Deposit Holds as Much Water as Lake Superior

jpl.nasa.gov

Post reply on HN
Print view View original

41–50 of 80 posts

Re: Mars Ice Deposit Holds as Much Water as Lake Superior

#41

Post by nickff »

sosborn wrote: post #40
scardine wrote: post #37

Earlier quoted context omitted.

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.

Re: Mars Ice Deposit Holds as Much Water as Lake Superior

#42

Post by InclinedPlane »

techterrier wrote: post #3

Or mud, as this stuff otherwise known.

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.

Re: Mars Ice Deposit Holds as Much Water as Lake Superior

#43

Post by bache »

reddytowns wrote: post #30
flippyhead wrote: post #22

Earlier quoted context omitted.

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

Re: Mars Ice Deposit Holds as Much Water as Lake Superior

#45

Post by leojg »

jessewmc wrote: post #39
557833 wrote: post #7

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

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…

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!

Re: Mars Ice Deposit Holds as Much Water as Lake Superior

#46

Post by AgentME »

scardine wrote: post #37
personjerry wrote: post #35

Earlier quoted context omitted.

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.

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.

Re: Mars Ice Deposit Holds as Much Water as Lake Superior

#47

Post by thaumaturgy »

sosborn wrote: post #40
scardine wrote: post #37

Earlier quoted context omitted.

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?

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

Re: Mars Ice Deposit Holds as Much Water as Lake Superior

#48

Post by Animats »

stcredzero wrote: post #9
peeters wrote: post #4

Earlier quoted context omitted.

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.)

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.

Re: Mars Ice Deposit Holds as Much Water as Lake Superior

#50

Post by blhack »

sosborn wrote: post #40
scardine wrote: post #37

Earlier quoted context omitted.

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?

...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.

Post reply on HN