Where in the World is Mars' Water? (axios.com) 102
An anonymous reader shares an Axios report: In the beginning, Mars was a water world. But at some point in Mars' distant past, much of that water disappeared, leaving behind polar ice caps and a complex geology. Figuring out just where it went has been a major priority for scientists -- life as we know it can't exist without water, and any future settlers would need a steady supply. A new study, published Wednesday in Nature, suggests that much of what remains might in inaccessible. Some went into space, but even more of it may have sunk into the ground like a sponge, only to become bound up in minerals deep within the planet. "Mars, by virtue of its chemistry, was doomed from the start," study author Jon Wade, of Oxford University, tells Axios.
Re:No hope of terraforming (Score:4, Informative)
So, this would imply that we could never terraform Mars because it cannot maintain surface water.
We couldn't with today's technology, nor tomorrow's. Long term? Who knows. There is lots of water out in space. Many comets and asteroids contain bunches of it. If you could harvest them and send them to Mars- you could probably create temporary surface water... over the millennia it will sink into the planet again- you'd need to keep "topping it off". Losing water to space is a big problem too... you'd need to try and keep an atmosphere- again, you could probably create one, but need to keep "topping it off" over the millennia by pumping more gas out.
You can terraform Mars but it will revert back to it's current dead-state if you don't keep maintaining it. A bit like a field. You can plough a field and harvest wheat one year... the next it might self seed and have some coming back that you can harvest, the next a little less, the next a little less... eventually you're going to need to replough the field, rotate the crops, replant, etc, if you want that field to feed you.
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This is a ridiculous idea. There is no way to transfer water to Mars from comets or asteroids that don't involve a massive transfer of kinetic energy at the same time as the comets arrive at the bottom of the Mars gravity well. It was a viable avenue to get water to the planet very early on in the planets history, but for terraforming purposes it's just not a solution. You'd be further ahead to send people down there with a thermos of coffee and a six pack of lager to piss all over everything.
You wouldn't have to crash them into the planet. Position them into close orbit and allow them to "burn up" in the atmosphere.
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It is as "non-existent" as Earth's atmosphere at 35 km, where some fixed wing aircraft have flown, and 40 km below where meteors typically burn-up.
To deposit comet material on Mars you would probably put the comet in a low circular orbit where drag becomes significant, and start breaking off small chunks to de-orbit and mostly vaporize in this "nonexistent" atmosphere. This should be an easily controllable process. If you blast material off the trailing side you could give the main body small boosts, while
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The atmosphere that is a hundredth of Earth's, where surface gasses evaporate?
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The atmosphere that is a hundredth of Earth's, where surface gasses evaporate?
Anyone hoping to terraform a planet overnight would be disappointed. An atmosphere would have to be established before the water to prevent it all being stripped away in the first place. If you want water to stay put on the surface, you need an atmosphere first.
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The atmosphere that is a hundredth of Earth's, where surface gasses evaporate?
Anyone hoping to terraform a planet overnight would be disappointed. An atmosphere would have to be established before the water to prevent it all being stripped away in the first place. If you want water to stay put on the surface, you need an atmosphere first.
You'll also need a magnetic field to keep it there, which Mars currently does not have. Terraforming Mars is a fun idea, but I doubt it will be achievable for a very long time. We can barely get off our own planet, and are currently pretty bad at managing its resources. It will be scores of decades, if not centuries, before we can undertake something like terraforming another planet.
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Even without a magnetic field the atmosphere would last a few dozen million years.
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An interesting idea, unfortunately probably completely unrealistic - there just aren't enough asteroids to make a difference. The combined mass of the entire asteroid belt is estimated at only about 4% that of the moon, or 0.45% that of Mars. Not enough to noticeably alter it's mass. As for re-liquefying its core - you're applying energy from the outside, and heat can only flow form areas of higher temperature to those of lower temperature. So you'd have to liquefy the surface long before you liquefied
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That would depend entirely on the flight path of the asteroids.
If you slowed them just enough to fall in to Mars' orbit, then you're correct. If instead you slowed them about twice as much, so the semimajor axis of their new orbit was the same as Mars', then there would be no net change in distance, and the eccentricity changes could be averaged out. Slow them even further and you could actually shrink the orbit of Mars.
Of course we're still only talking a 0.45% change in mass, so the differences would on
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This is a ridiculous idea. There is no way to transfer water to Mars from comets or asteroids that don't involve a massive transfer of kinetic energy at the same time as the comets arrive at the bottom of the Mars gravity well.
Let us do a little arithmetic here.
Say we want to add 1 kg of volatiles per square centimeter of Mars' surface. This is the equivalent of an atmosphere as thick as Earth's, but in this case would be split between gases and water. So, 10,000 kg per square meter. The orbital velocity of Mars is 2.1 km/sec, which means that 10,000 kg mass starts with 2.2 x 10^10 J. Insolation at Earth's orbit is 1367 W/m^2, so this is equivalent to 16.1 million seconds of sunlight hitting Earth's atmosphere at zero obliquity,
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Don't need to terraform the whole thing. Create a network of massive enclosed subterranean biospheres in the caves, link em by transport tunnels, mine for water and needed minerals as needed. Its kind of a crappy existence but a little better once you get some kind of ecosystems going and artificial skies. You might be able to run solar tubes down (filtering out radiation of course) if its near the equator you might even pipe in enough natural light during the day through radiation filtered solar tubes (it gets up to 70 degrees sometimes although down to -100 at night).
Like on Total Recall before Arnie restarted the blowy things?
Re: No hope of terraforming (Score:2)
you'd need to try and keep an atmosphere
Re-spin the core, fire up that magnetic field; voila! Atmosphere contained. I believe there's a documentary where they did something like this.
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you'd need to try and keep an atmosphere
Re-spin the core, fire up that magnetic field; voila! Atmosphere contained. I believe there's a documentary where they did something like this.
If they've made a documentary about terraforming Mars, I am at a loss as to why Mars isn't, um, terraformed.
Anti-Mars propaganda (Score:2, Interesting)
Only 3% of Earth's water exists as fresh water that would have been consumable by humans in prehistoric times. Does that mean that Earth was not inhabitable? Humans don't need much water on a geological scale and there is plenty on Mars in ice at upper latitudes and in mineral salts everywhere.
As far as terraforming, the ability to hold surface water depends on atmospheric pressure and that depends on getting all that frozen CO2 and water vapor into the air.
Re:Anti-Mars propaganda (Score:5, Insightful)
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and keeping the CO2 and water vapor in the air rather than getting stripped away by the solar winds only requires melting the core of Mars to get a magnetic field going again (of course assuming the core is largely ferrous, which I'm not sure what the composition of it is).
So.... (Score:3)
Geology? (Score:3)
Do planetologists use the term "geology" when they're talking about another planet?
Re:Geology? (Score:5, Informative)
Plus, geology is a much wider used and understood term. If I say I am working in the field of geology specializing in the mineral chemistry of Mercury, your average layman will understand me, but the term Hermeology might cause confusion.
Planetary Geology [Re:Geology?] (Score:5, Informative)
Do planetologists use the term "geology" when they're talking about another planet?
Technically, no, the proper term for the study of Mars planetary formation, mineral chemistry etc is areology.
It etymologically ought to be areology, but it turns out that having a different word for the geology of each planet was too cumbersome, so they are all lumped together as "Planetary geology."
https://scienceandtechnology.jpl.nasa.gov/research/research-topics-list/planetary-sciences/planetary-geology-and-geophysics [nasa.gov]
http://planetary-science.org/planetary-science-3/planetary-geology/ [planetary-science.org]
and geologists routinely use the term "Martian geology" and "geology of Mars"
https://mars.nasa.gov/programmissions/science/goal3/ [nasa.gov]
http://planetary-science.org/mars-research/surface-geology-of-mars/ [planetary-science.org]
https://www.exploratorium.edu/video/martian-geology-101 [exploratorium.edu]
https://www.geol.umd.edu/~jmerck/geol212/lectures/01.html [umd.edu]
Re:Geology... (Score:2)
I'm piggy-backing on the geology thought...
I would like to see the next Mars rover mission equipped tools to "see" deep below the surface. For example, a moveable geophone system or ground-penetrating radar, or land stationary seismic detectors around the planet to monitor long-term like we do on Earth. Mars missions so far have only scratched the surface (literally) and taken photos. We have enough surficial information to say with some confidence that if there's anything really interesting going on with M
Under the surface [Re:Geology...] (Score:2)
I would like to see the next Mars rover mission equipped tools to "see" deep below the surface. For example, a moveable geophone system or ground-penetrating radar, or land stationary seismic detectors around the planet to monitor long-term like we do on Earth.
Your wish is granted: the next NASA mission, Insight, has a five-meter drill, and also a seismometer.
https://insight.jpl.nasa.gov/h... [nasa.gov]
Launches May 2018.
Mars missions so far have only scratched the surface (literally) and taken photos.
Two of the Mars orbiters had ground-penetrating radar: SHARAD on the Mars Reconnaissance Orbiter and MARSIS on Mars Express.
SHARAD: https://mars.nasa.gov/MRO/mission/instruments/sharad/ [nasa.gov]
MARSIS: http://sci.esa.int/mars-express/34826-design/?fbodylongid=1601 [esa.int]
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Cool. I should have done some research myself first. I guess that information doesn't get as much attention as pretty pictures. The resolution on satellite based GPR has to be massive. The seismometer is really cool. Although I would prefer several stationary seismometers deployed long-term around the planet, but one mobile seismometer will have to do. I am very skeptical of how much planetary information can be obtained from a mere 5-meter drill, but we'll see...I'd like to be surprised. I suspect the dril
The Waters of Mars? (Score:3)
https://en.wikipedia.org/wiki/... [wikipedia.org]
Thought this was settled? (Score:4, Insightful)
I thought it was pretty much settled? Thin atmosphere, solar radiation disassociated water into hydrogen and oxygen, the hydrogen left, the oxygen combined with various minerals. At least, that's what I had learned...
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I thought it was pretty much settled? Thin atmosphere, solar radiation disassociated water into hydrogen and oxygen, the hydrogen left, the oxygen combined with various minerals. At least, that's what I had learned...
For our lifetime, or our kids lifetimes, absolutely... 500 years from now... I'm placing no bets.
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The article implies that while photo-disassociation of water after the collapse of the planet's magnetic field was one factor in the loss, another larger process was the sequestration into the planets mantle.
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No magnetic field either
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one planet over. (Score:2)
Forget the water (Score:2)
Maybe they should invest in a sleepcheckers instead.
Sorry, I drank it (Score:4, Funny)
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It's never too obscure for /.
But just in case it is: https://www.youtube.com/watch?... [youtube.com]
Where? (Score:2)
Too bad (Score:2)
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If Mars had a Racnoss ship as its core like Earth does it might have been better at sustaining life.
Until the children are awakened!
"Water-sculpted" landscape? (Score:4, Interesting)
It ain't the long-gone water, it's the thin but ever-present wind.
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Although there are also aeolian features on Mars, wind doesn't carve the particular kinds of features in the Viking images that are the ones mostly attributed to water, e.g., http://solarviews.com/cap/mars... [solarviews.com]
Geologists argued for a long time, though, about whether the fluid that carved the features was actually water, or some other fluid. But now that we have ground truth measurements from the rovers, the case for water is pretty well established.
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https://www.nasa.gov/sites/def... [nasa.gov]
Wind doesn't produce branching riverbeds filled with rounded stones.
Did you check Uranus? (Score:2, Funny)
Did you check Uranus?
Uranus, the water world (Score:2)
Although I expect that this remark was intended to be some kind of humor, but in fact, it's accurate: Uranus is a planet composed mostly of water.
https://www.universetoday.com/19309/water-on-uranus/ [universetoday.com]
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Uranus is a planet composed mostly of water.
But curiously, it rains diamonds on Uranus: https://www.kidsdiscover.com/q... [kidsdiscover.com]
Where do you think? (Score:3)
There is no viable alternative to Earth (Score:1)
Any thoughts that settling another planet is easier than dealing with the solvable issues on this planet are absurb. Establish a colony on Mars in the name of scientific exploration? OK, maybe it is feasible. But to view Mars as a new Earth with large human populations? Not feasible with foreseeable tehnology! The energy required is huge the likelihood of long-term success is small. We will never have a self sustaining settlement that is not vulnerable to a cascade of mechanical failures that lead to
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One of the concerning things about it as well due to the failure of mechanical systems, it would seem such colonies would be constantly dependant on imports from earth to maintain it. Earth already has its own resource problems without supporting colonies on other planets. unless a colony can be completely self sufficient, it would damage earth's resources.
At best, it might be able to host a small scientific colony but the idea of any large scale population is really, really far fetched.
The absurdity of mar
Polar caps of Mars [Re:Dumb summary] (Score:2)
But at some point in Mars' distant past, much of that water disappeared, leaving behind polar ice caps and a complex geology.
Aren't ice caps made of water?
Yes, the permanent ice caps of Mars are water ice (the seasonal ice is primarily frozen carbon dioxide, aka "dry ice").
But, although they are miles thick, the Martian ice caps are just too small to contain all of the amount of water that early Mars is believed to have once had. The polar caps contain a small amount of it, but the question being addressed here is, what happened to the rest of it?
It sank (Score:3)
... into the ground.
The earth's water is kept on the surface by geothermal heat. Any water that trickles down through fissures is quickly heated and vented back into the atmosphere as steam. Mars' geothermal output has cooled to the point that there is little, if any active volcanism. And so the water stays underground.
The same place you'll find... (Score:2)
Carmen Sandiego.
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True Location (Score:1)
This is the same place it originated from.
The intent is to burn off immeasurable amounts of tax payers resources just as the Martian atmosphere has been burned away by the Sun.
I am the author (Score:1)
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Might it not be easier to reengineer the human body to no longer require regular intake of water, than to squeeze it from stones in other environments like Mars?
In related news: Plans to find the water ... (Score:2)
Its covered by space dust (Score:2)
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Wow. Yet another post where I can't tell whether it's deadpan parody, or dead-on clueless.
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sufficiently advanced satire is indistinguishable from idiocy.