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Despite Clay Minerals, Early Mars Might Have Been Dry

Posted by timothy on from the but-omg-mars dept.

astroengine writes "Early Mars may not have been as warm or wet as scientists suspect, a finding which could impact the likelihood that the Red Planet was capable of evolving life at the time when it was getting started on Earth. A new study presents an alternative explanation for the prevalence of Mars' ancient clay minerals, which on Earth most often result from water chemically reacting with rock over long periods of time. The process is believed to be a starting point for life."

70 of 105 comments (clear)

  1. Hmmm... by EddyGL · · Score: 2, Interesting

    How does this explain away the alleged river channels, deltas, salts found by the rovers, etc... etc... and other evidence of large amount of water?

    1. Re:Hmmm... by jellomizer · · Score: 1

      Volcanic activity?

      --
      If something is so important that you feel the need to post it on the internet... It probably isn't that important.
  2. They keep changing the narrative.. by tetrahedrassface · · Score: 5, Informative

    This isn't new news, but the scientific establishment that gets the budgets to conduct space exploration is selling us Mars because they know it is doable within the context of current budgets and technologies. Mars is pretty much way too dry and has been. It also lacks a magnetosphere and despite *one lame little plate* any hint of past large scale plate tectonics. Mars is interesting for sure, but it would be nice to also have a real base on luna with which to assemble a vehicle to take us on to Mars and with which to test technologies with the intent of sending humans on to Mars. Europa and even Venus deserve attention as well, but it seems Mars is in our comfort zone so we keep going back....

    1. Re:They keep changing the narrative.. by fsck1nhippies · · Score: 1

      I too would much rather see an investment in the moon. It is close enough that we can courier equipment, people, and supplies with the intent of setting up a foothold in space. I think it would take years to get to the point where we have a significant presence there, but having that reduced atmosphere and reduced gravity environment would most likely further our capabilities quite a bit more than speculating on the amount of water Mars had in the past.

      Stage supplies in earth orbit while building a basic transport ship. Move everything out to the moon and start landing the stuff on the surface. We can put people in orbit for a year, but we can't put them on the moon for 2 weeks?

      I think we are misguided in the space program (in case you can't tell).

    2. Re:They keep changing the narrative.. by Anonymous Coward · · Score: 1

      luna? You mean the moon, right?

    3. Re:They keep changing the narrative.. by ColdWetDog · · Score: 4, Interesting

      Not much on the moon of any use. Mining stuff anywhere off earth is a long way from being practical. If you want to build a transfer station, do it in orbit (like LEO, just what the ISS is doing).

      Personally, I'd like us to spend more money and time on the Jovian satellites but then again, I'd like NASA to get to spend more money - lots more money. At the current piddly rate we're funding space exploration, you really can't expect to be able to pull off any major exploration goal. Right now we're just doing simple and cheap things (relatively speaking) and hoping that the funding situation gets better.

      You can certainly argue all day about whether or not it's an appropriate goal for a country, but you're not going to get very far with the nickel and dime approach we're currently using. Not that JPL isn't doing neat science - and given the financial limitations that they work in, they've done a fantastic job, it's just to really answer a lot of the questions we are posing and to enable us to even think about pulling resources from space, we're not doing jack.

      --
      Faster! Faster! Faster would be better!
    4. Re:They keep changing the narrative.. by fsck1nhippies · · Score: 3, Interesting

      I completely agree with the "nickel and dime" approach. I was not suggesting that we mine the moon for resources. My use of the moon is to give us a stable structure to build a base on.

      The ISS is an awesome idea, but we limit our exposure to space by just sending supplies and equipment to the same spot without ever reaching further. The shuttle program was definitely a success if you are willing to limit your goals to just looking down on the earth in awe. Had we spent those 135 missions pushing toward the settlement of a body outside of earth, we would be further along. Hell, just 20% of them could have built an outpost on the moon.

      Don't get me wrong, I am glad we invested in the shuttle program. I just wish we used it to expand our capabilities instead of just doing the same thing over and over.

      Yeah, we are definitely underfunding the space program... I can draw similarities between our handling of the space program and our approach to education.

    5. Re:They keep changing the narrative.. by bhcompy · · Score: 1

      Yes, but I would hope that the plan is to use Moon materials to produce as much as possible. Hell, you could even just grab all that dead shit floating around in orbit to do something. At that point, it's like a used car. Manufacturing and most of the delivery cost doesn't even matter.

    6. Re:They keep changing the narrative.. by khallow · · Score: 4, Informative

      2) It currently costs tens of thousands of dollars to put a single kilogram of mass into space. If you're going to get any kind of industry up there, it's going to cost trillions of dollars.

      It's currently around $5,000 per kg for the Russian launch vehicles. SpaceX threatens to halve that cost.

    7. Re:They keep changing the narrative.. by Baloroth · · Score: 4, Insightful

      The advantage to the moon is assembly of parts can be done their under the effects of gravity. Assembling large projects from parts might sound easier in micro-gravity, but maneuvering becomes such a pain it's a lot easier for humans to work under gravitational effects (it's how we evolved to operate). It also has signs of ice for water, so you could potentially use it as a cheap source for that, and may well have other viable minerals usable in space exploration. We are a far way from mining the Moon for Earth use. Unless we find some extremely rare mineral there (like Platinum), most stuff we need is vastly easier to find on Earth. No, mining and manufacturing on the Moon would be as a staging ground for further exploration. Escape velocity there is ~1/3 Earth's, so it's about as easy to transfer from there to deep-space as it would be from LEO anyways.

      Not to mention it would serve as a nice test of our ability to establish a base on another world without being out of (relatively easy) reach of Earth, and there is a ton of Lunar science to be done on the surface yet.

      --
      "None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
    8. Re:They keep changing the narrative.. by tetrahedrassface · · Score: 1

      A big *amen* to both of you.

    9. Re:They keep changing the narrative.. by theshowmecanuck · · Score: 1

      Tell congress there are Arabs and Oil on Titan and there'll be 300,000 marines there inside a month. Seriously, if they would spend even a part of the money that is spent unnecessarily on defence (seioursly... with that kind of spending how can they calll it defense?), there would not only be a moon base, but Disneyland and NFL franchises there AND on Mars. It is a fact that America spends almost as much money on its military as all other countries combined. If you want a reason why things aren't happening the way they should be, look at that number. And the repubicans want to spend MORE on the military. And never mind moon bases (which would be awesome), think of what could be done with healthcare (but why... can't we decrease the surplus population Ebenizer?). But that is another subject.

      --
      -- I ignore anonymous replies to my comments and postings.
    10. Re:They keep changing the narrative.. by theshowmecanuck · · Score: 1

      I read somewhere that once you get into orbit, it isn't that much of a difference in terms of resources, getting from there into Lunar orbit versus Martian orbit. The first step is a doozy though.

      --
      -- I ignore anonymous replies to my comments and postings.
    11. Re:They keep changing the narrative.. by TFAFalcon · · Score: 1

      It's not just the 400KM. It's the 400KM + orbital speed. Once you've got that, you no longer need great big fuel guzzling engines to quickly get above the atmosphere. You can start using low thrust but high efficiency engines, like ion drives. Sure they may be slow, but if you aren't in a hurry they'll get you wherever you want.

    12. Re:They keep changing the narrative.. by khallow · · Score: 1

      Moon is harder to do than Mars. There's nothing in Moon which you can reuse easily, whereas in Mars there's plenty.

      I'd suggest actually looking at proposed ISRU on the Moon. It has oxygen and various metals that can be obtained anywhere on the surface. That's in addition to the volatiles at its poles.

      You could terraform Mars to have a thicker atmosphere. You cannot do this with the Moon.

      So what? You have other things you can do with the Moon that are more productive than merely turning it into another Earth.

      Mars has more gravity, too.

      That's a drawback not a selling point. The primary value of the Moon will be what it can deliver to Earth orbit cheaper than can be delivered from Earth.

      Check Zubrin's book, "The Case for Mars" which has plenty of arguments and points.

      That's a good source, but keep in mind Zubrin was and is heavily biased against development of the Moon.

    13. Re:They keep changing the narrative.. by DerekLyons · · Score: 1

      I completely agree with the "nickel and dime" approach. I was not suggesting that we mine the moon for resources. My use of the moon is to give us a stable structure to build a base on.

      The problem is - it costs an order of magnitude more to reach the moon, and you no more need a "stable base" than you a fish needs a bicycle.
       
      You also make your [Mars bound[ space craft more expensive by requiring to boost from the surface of the moon, and by adding the need to endure the [harsher than LEO] lunar temperature environment.
       
      Building a base on the moon to support exploration further out is like building a base in the middle of the Sahara desert to support deep ocean exploration or Antarctic expeditions... all you accomplish is making the whole affair much more expensive and difficult. I know it sounds like heresy to many, but you're far better off building a base in Charleston (SC) or Seattle (WA) to do either, and the same is true of LEO and going beyond the moon. The infrastructure and support costs are far lower, and transportation costs a barely visible fraction.
       

      The shuttle program was definitely a success if you are willing to limit your goals to just looking down on the earth in awe. Had we spent those 135 missions pushing toward the settlement of a body outside of earth, we would be further along. Hell, just 20% of them could have built an outpost on the moon.

      20% of Shuttle flights is roughly 25 flights - not even enough for a handful of Apollo class missions.
       

      Don't get me wrong, I am glad we invested in the shuttle program. I just wish we used it to expand our capabilities instead of just doing the same thing over and over.

      We're no more doing the same thing over and over at the ISS than we are in Antarctica. You confuse repeated trips to the same facility with the work done *at* the facility. You also fail to realize that much of the work is long term, this is real science and real engineering - not the surface impression you get from an hour (less commercials) of a show on the Discovery channel.

    14. Re:They keep changing the narrative.. by CrimsonAvenger · · Score: 1

      You also make your [Mars bound[ space craft more expensive by requiring to boost from the surface of the moon, and by adding the need to endure the [harsher than LEO] lunar temperature environment.

      Won't argue about temp issues, but it takes rather less deltaV to go from Luna surface to a Mars transition orbit than it does to go from LEO to a Mars transition orbit.

      Never mind that we can get reaction mass and/or fuel from the Moon....

      --

      "I do not agree with what you say, but I will defend to the death your right to say it"
    15. Re:They keep changing the narrative.. by DerekLyons · · Score: 1

      You also make your [Mars bound[ space craft more expensive by requiring to boost from the surface of the moon, and by adding the need to endure the [harsher than LEO] lunar temperature environment.

      Won't argue about temp issues, but it takes rather less deltaV to go from Luna surface to a Mars transition orbit than it does to go from LEO to a Mars transition orbit.

      True, but when you add in the deltaV to get to the Moon in the first place... plus all the costs associated with getting the base built and supported and boosting the materials and equipment to the Moon... The few tens of thousands of dollars you 'save' in fuel start to look like the chump change they are.
       
      Fuel on earth is virtually dirt cheap. (It cost less than a million dollars to fill the Shuttle's external tank.) Complex Rube Goldberg schemes that cost many tens (or hundreds) of billions of dollars don't reduce fuel cots - they increase them massively.
       

      Never mind that we can get reaction mass and/or fuel from the Moon....

      At a cost somewhere in the range of hundreds to thousands of times what it costs to boost the fuel directly from Earth into LEO.

    16. Re:They keep changing the narrative.. by Chris+Burke · · Score: 1

      Mars is pretty much way too dry and has been.

      It's true that Mars is chosen as a target for rover missions because it's "easy" enough as such things go. Before sending rovers to farther and/or vastly more hostile places, it makes sense to bone up on the tech on Mars, eh?

      But the reason the "scientific establishment" maintains interest in Mars is because, rather than being happy with unsubstantiated declaratory statements like the above, they actually want to know.

      --

      The enemies of Democracy are
    17. Re:They keep changing the narrative.. by HiThere · · Score: 1

      FWIW, a granparent or so complained that the space program was as underfunded as education. I.e., our priorities are such that the most important future leaning activities are underfunded (or so I understood it).

      OTOH, I'm not convinced that orbit is such a great place to build things until AFTER we have captured an asteroid, or build a catapult on the moon. There's no materials there to build from, and lofting everything from Earth is rediculously expensive. I suppose a space elevator could solve this, but building that won't happen until long after space is reasonably used. So my favorite skyhook is a thing called a pinwheel. Much cheaper, much easier, quite flexible. And much safer. It's true that it also doesn't reduce costs as much, and like any skyhook, you need to bring down as much mass as you lift up, or the orbit decays.

      Moon bases are a good idea because the moon is a decent place to set up a catapult to get mass into orbit. (But you still need to work on a closed ecology. This use it once and thow it away is ok for ammunition, but lousy for a base. Especially for air and water. (For a base use it once can be construed to mean for several decades, so use it once isn't so bad. But for the air you breathe or the water you drink, it's not such a good approach. Or for the food you eat.) If we don't improve the "closed ecology" capabilities, then space exploration will clearly be the province only of robots.

      --

      I think we've pushed this "anyone can grow up to be president" thing too far.
    18. Re:They keep changing the narrative.. by Gripp · · Score: 1

      Mining stuff anywhere off earth is a long way from being practical.

      Yes.... but I think from the very lengthy debate that follows your post it's clear that everyone agrees we need to start launching less from earth and more from orbit.
      The problem I see with this is that we still have to launch from earth to get there. I think eventually we will be able to mine and manufacture in space, limiting the need to launch from earth to only getting people or specific/complex devices up there. Ultimately allowing us to build much bigger and better space "stuff" . And IMO starting the first steps of this process are more important than trying to leap frog it. And we'll never get to a point where it is economically feasible if we don't start putzing with it to figure out how to get there.

    19. Re:They keep changing the narrative.. by CrimsonAvenger · · Score: 1

      True, but when you add in the deltaV to get to the Moon in the first place... plus all the costs associated with getting the base built and supported and boosting the materials and equipment to the Moon... The few tens of thousands of dollars you 'save' in fuel start to look like the chump change they are

      This is only true if the only thing you're using the Moon for is a fuel depot. Actually building large parts of your Mars vehicle on the Moon.makes a certain amount of the problem of boosting those same large parts out of Earth's gravitywell.

      Note also that a base on the Moon will be unable to actually manufacture everything, aluminium and titanium are available inn quantity.

      Note further that lifting things off from Earth to LEO requires that you burn fuel (in large amounts) just to carry the payload (that fuel you want to brush off as important. Fuel usage to carry fuel to LEO in large quantity - like 1/5th the takeoff mass (best case, using SSME). On the other hand, using a 350 Isp rocket fuel gives you something like ~2% of your boost mass over to fuel.

      --

      "I do not agree with what you say, but I will defend to the death your right to say it"
    20. Re:They keep changing the narrative.. by khallow · · Score: 1

      The main problem with Moon is 1. lack of water and 2. you need a lot of energy to do anything on the Moon.

      1) There are other things you can do that don't require water. Such as shipping oxygen and manufactured parts to Earth orbit and the Lagrange points.

      2) You have a lot of energy to use: 1,300 W per square meter. It's halved on Mars.

      To grow your food on the Moon you need at least water and artificial lighting and heating. Where to get the energy for lighting? Solar panels won't work, unless you're on the pole, due to long shadow period.

      Most which you have just from solar power. Storing power for two weeks is a bit of a challenge, but not a great one.

      What about heating?

      Geothermal. Drill a deep hole anywhere on the Moon and you'll tap into the warmth of the interior.

      Also to get from the Moon to the asteroid belt is difficult. Mars is much closer.

      The Moon's market is Earth and Earth orbit. That is the main draw for the Moon, being right next door to the most valuable real estate in the Solar System.

      Sure the Moon is great to send stuff to Earth orbit, but what do you plan on sending?

      Finally, we have a good question. For volatiles, the Moon has plenty of oxygen. That's useful both as chemical rocket propellant (which would probably be its primary use) and human consumable (being the primary component by mass of water and the active ingredient in any sort of breathable air).

      Then there's the metals. The Moon has a lot of aluminum, iron, titanium, and other metals in its crust. Even without an advanced technology base, one could make structural components for spacecraft and stations. As long as mass remains expensive to lift out of Earth's gravity well, that's going to mean that the Moon has a competitive edge.

      The Moon also has no atmosphere and a relatively low gravity well compared to either Earth or Mars. That plus the relatively high energy environment means that launch systems such as magnetic rail or gas guns are quite feasible. In comparison, I think that Earth is going to be stuck with chemical propulsion for a while to lift payloads into orbit. That puts Earth at a substantial advantage compared to Mars, the Moon, or of course, any other small body.

  3. Hmm by lightknight · · Score: 1, Interesting

    Even though it's Sci-Fi, I almost like to believe that human beings move from planet to planet, using up local resources and destroying them.

    The cycle would be constant, and self-fulfilling: We use technology to get off the old planet, and to settle onto a new one. Then a generation or so later, we blame the evils that destroyed the old planet on our technology, and swear it off so we can 'commune' with nature / our new home. This works for a few more generations until we realize that it wasn't technology that destroyed our old home, but our actions and stupidity. Then we we fight over how to 'save' our new home from ourselves, with half being against technology, and half being for it. Thus we are stuck in a disagreement, we try to do accomplish both angles at once. Something happens during this time (it's unknown, but recurring on every planet, and the records are always purged), and humanity begins fighting itself. The result of this fight ends in the doom of our new home, and we use technology to move onto yet another planet.

    To this degree, Mars and Venus may have been habitable planets (as well as the others) that have been destroyed by odd processes. And in time, they may become habitable again.

    --
    I am John Hurt.
    1. Re:Hmm by VortexCortex · · Score: 2

      Your theory ignores Evolution and the Fossil Record. However, if you were to say simpler forms of life (or even just matter) spreads from place to place and evolves on the planets, using up resources (and get rid of the predictions of what ultimately happens), then you have something very much like reality...

    2. Re:Hmm by Riddler+Sensei · · Score: 1

      Then we we fight over how to 'save' our new home from ourselves, with half being against technology, and half being for it. Thus we are stuck in a disagreement, we try to do accomplish both angles at once.

      Kind of reminds me of Anno 2070.

    3. Re:Hmm by ColdWetDog · · Score: 2

      So where are the ancient Martian cities? The radioactive craters? The garbage?

      If there was a civilization capable of destroying the ecosystem, I think you'd see it given the multiple, high resolution surveys we've done.

      --
      Faster! Faster! Faster would be better!
    4. Re:Hmm by khallow · · Score: 1

      Even though it's Sci-Fi, I almost like to believe that human beings move from planet to planet, using up local resources and destroying them.

      While some repliers have noted the lack of realism, I find the psychological aspect interesting. Why do you want such a story? Wouldn't a story where humanity was a constructive influence on the universe be better even if a tad boring?

    5. Re:Hmm by Third+Position · · Score: 4, Insightful

      Not necessarily. We have plenty of civilizations on Earth that have barely left a trace, and the oldest of those is only a few thousand years old. If there were civilizations several hundred thousands or millions of years old, chances are pretty good we could miss them, even in our own back yard, let alone on another planet.

      --
      American Third Position
      Finally, a real choice!
    6. Re:Hmm by rubycodez · · Score: 1

      no, venus and mars will never become habitable, venus will not become cooler, nor mars wetter. most planetary bodies in the universe cannot support life. It is fine for humans to use the empty unihabitable things in any way they want, nothing of value will be lost.

    7. Re:Hmm by spauldo · · Score: 2

      Any civilization that old would have left nothing to show its existance. Even the pyramids won't last that long.

      A biosphere, however, leaves its mark on a world. You'd be able to tell easily if Mars or Venus was habitable by humans duing the time homo sapiens has existed.

      --
      Those who can't do, teach. Those who can't teach either, do tech support.
    8. Re:Hmm by Anonymous Coward · · Score: 1

      That's nonsense. In desert areas we can see city streets outlining ruins in satellite images where the ground indications are pretty subtle. Human activities at the scale we would call "civilization" leave behind plenty of evidence. They need building materials, agriculture, irrigation, transportation, etc. All of those leave evidence, particularly in arid, unvegetated areas. If there were civilizations that old, they would have to be very well hidden (like on the bottom of the Antarctic or Greenland ice sheet, the bottom of the ocean, or deep in a jungle). On Mars there isn't even an ocean to hide under. It's pretty much laid bare except for the polar ice caps. Any Martian civilization would have to be underground, and stay there (never venture onto the surface or disturb it). It's not like we've surveyed every scrap of the Earth, but you also don't have to find the location of a civilization in order to know that it was around in a region or somewhere on the planet. For example, there are clear signatures of lead and other types of smelting that show up in ocean and lake sediments in any region that had active metalurgical industries. You can peg when humans moved into the region by analyzing the chemistry of the sediments in a vertical section. You don't even have to know where they are. Just look at the sediments out the mouth of a major river and you can detect the activity anywhere in the drainage basin. You'd have to have an extraordinarily "clean" civilization for it to escape detection somehow, especially if they ever did anything involving nuclear technologies. That would be detectable easily by isotopic signatures anywhere on the planet. If there was a Martian civilization, they must have ended in an orderly and very tidy fashion, because they would have to go out of their way to not leave obvious signs. It would take a concerted effort.

      I'm sure K'Breel would explain the great lengths his society has had to go to in order for it not to be detected by humanity, but that would kind of give things away.

    9. Re:Hmm by spauldo · · Score: 1

      Monuments are the wrong clue to look for.

      True, but they're the most obvious. It might take quite a bit of study to identify signs of an ancient civilization based on land shaping and rock distribution. The pyramids are obviously artificial.

      While an advanced macroscopic surface biosphere would indeed be easily detectable, these [sciencemag.org] types of organisms would not.

      Those types of organisms wouldn't support a civilization, either. Mars has obviously never had a diverse biosphere that could support advanced forms of life (at least as we understand it), so there's little point to searching for Martian artifacts. I'm all for searching for the Martian equivalent of bacteria and archea.

      I'm not sure we know enough about Venus to say one way or the other, but I'll readily admit my ignorance on the subject. I've always found Venus to be dull and haven't spent much time reading about it.

      --
      Those who can't do, teach. Those who can't teach either, do tech support.
  4. What about this? by RichardtheSmith · · Score: 3, Insightful
    I'm sorry, when they taught me Earth Science they mentioned that stratification was caused by sedimentary rock, laid down by the action of water over millions of years.

    How do you explain this without water?

    http://i.space.com/images/i/20995/wS4/mount-sharp-1600.jpg?1346122345

    1. Re:What about this? by cunniff · · Score: 3, Insightful

      Well, it could be sedimentary rock layers. But volcanos can also cause layering - consult the oracle about "welded tuff" (example image from Idaho)

    2. Re:What about this? by wbr1 · · Score: 4, Funny

      Those are scars left by martian strip mining and martian mountaintop coal removal crews.

      --
      Silence is a state of mime.
    3. Re:What about this? by zrbyte · · Score: 1

      Yeah. And what's with all the dried up riverbeds?

    4. Re:What about this? by VortexCortex · · Score: 3, Interesting

      Not that I disagree that water was the cause; However, all fluid is made of matter and can briefly suspend particles of other more dense matter thus providing the capability to form deposits and layering if said fluid is in motion. The Martian atmosphere is known to have Dust Storms -- I put it to you that these Dust Storms are such suspensions of matter having varied densities, and that the dust is, in fact, relocated. I believe that Mars was not always a solid rock because it shows evidence of volcanism -- Magma is also a fluid / matter suspension and is thus capable of forming layers of material. Unless we observe the actual layers and their material compositions we will not know how the layers formed.

    5. Re:What about this? by nospam007 · · Score: 2

      "How do you explain this without water? "

      It used dehydrated water.

    6. Re:What about this? by Dabido · · Score: 1

      When I did Geology at Uni in 1984 they explained sedimentary rock as just being formed due to it being deposited and building up over time. Water was only one way (the main way), but debris blown by the wind and being deposited was another, as well as glaciers, ice, and even earth movement (ie a landslide - volcanoes - earthquakes). The water being nec. probably sticks in your head because on earth about 99% of all sedimentary rocks formed that way and either 1. your teachers didn't include the other ways as they probably thought none of the students would ever use the knowledge in life, and/or 2, because all the video's etc in earth sciences use visuals/animations that show water evaporating and leaving sediment behind that turns into stone. But the pressure, and some other factors are enough to cause the debris to turn into stone. Sedimentary rocks caused in deserts from the wind blowing the sediment is probably the most common 'non water' type of sedimentary rock formed. Who knows, on Mars it might be the most common cause of sedimentary rock. There is also nothing to say that there isn't enough moisture in the Martian atmosphere to help the sedimentary process. The 'dryness' they refer to in the article may be relative.

      --
      Sure enough, the cow costume was hanging up next to the superhero outfit and sailors uniform. (S,Spud)
  5. It's only natural. by Anonymous Coward · · Score: 1

    Men have a natural tendency to exaggerate how warm and wet things used to be.

  6. No magnetosphere, no mass by udachny · · Score: 4, Informative

    Mars has no magnetosphere, it's has 89% less mass, it is half of the Earth's diameter. Mars could never really sustain a breathable atmosphere with oxygen and nitrogen just because of those characteristics, those gases would simply fly off into space, there cannot be enough density and pressure on the surface of Mars to hold a breathable atmosphere.

    Of-course living organisms can survive in various other types of atmosphere, for example carbon dioxide, but even that gas cannot be held by Mars in enough density for anything to breath it.

    --
    MY OTHER COMMENTS
    1. Re:No magnetosphere, no mass by spaceplanesfan · · Score: 4, Informative

      Titan disagrees with you.

    2. Re:No magnetosphere, no mass by udachny · · Score: 1, Informative

      Mercury too has an atmosphere, but it's also not breathable.

      It's possible to have very heavy chemicals as an atmosphere on a smaller planet than ours, sure, at very different temperatures, very heavy compounds.

      --
      MY OTHER COMMENTS
    3. Re:No magnetosphere, no mass by udachny · · Score: 1, Informative

      Oh, and by the way, Titan is inside the magnetosphere envelope of Saturn.

      So does it still disagree with me?

      --
      MY OTHER COMMENTS
    4. Re:No magnetosphere, no mass by Third+Position · · Score: 1

      Sure, eventually those gases will escape into space. But that "eventually" is measured in tens of thousands of years. For purposes of terraforming, that's a reasonable life span for an atmosphere. And it leaves you plenty of time to figure out what to do for an encore.

      --
      American Third Position
      Finally, a real choice!
    5. Re:No magnetosphere, no mass by rossdee · · Score: 1

      "Breatheable" is a relative term. even on this planet lifeforms occupy some pretty tough niches.

    6. Re:No magnetosphere, no mass by Convector · · Score: 1

      While there is no global magnetic field today, strong crustal magnetism suggests that it must have had such a field in the past. Dynamo activity would have stopped once the core-mantle heat flow became unfavorable to core convection.

  7. Dry? by slick7 · · Score: 1

    A couple of distilleries and half a dozen microbreweries should end that dry spell.

    --
    The mind conceives, the body achieves, the spirit manifests.
    1. Re:Dry? by Lord_of_the_nerf · · Score: 2

      I know a couple of boys from Hazzard County that could solve it too.

    2. Re:Dry? by Sulphur · · Score: 1

      I know a couple of boys from Hazzard County that could solve it too.

      That's what happens when you have a dry planet. They probably cut a few channels on the way too.

  8. Re:Paper far from disproving wet Mars by Anonymous Coward · · Score: 1

    That doesn't prove water. That establishes liquid. That liquid might have been something other than water. Mars is farther from the sun and colder, so it doesn't even have to be something that would be liquid at Earth temperatures.

    This research doesn't actually prove anything. It just says that something we thought was proof wasn't. More exploration is needed to gather more data.

  9. But what about K'breel and friends? by Alex+Belits · · Score: 1

    Without water they wouldn't have gelsacs!

    --
    Contrary to the popular belief, there indeed is no God.
  10. Tunnel vision by Grayhand · · Score: 5, Insightful

    You can argue minerals all you want but it doesn't change the fact Mars has massive water features. Also they keep finding signs of sedimentary rock. Even some of the first rover pictures have shown it. Taking the evidence as a whole there shouldn't still be a debate about water on Mars. It's a waste of energy and resources. They should be focused on what happened to it? Was most of it lost to space or is it trapped deep in the soil?

    1. Re:Tunnel vision by AK+Marc · · Score: 4, Interesting

      There is no proof that the water features were caused by water. Mars bears geology that would require water on Earth. But that doesn't offer proof of water, just a strong hint. Continuing to look at it is likely being done with an eye on confirming it and figuring out what happened to it, if it was there. At this point, there is no proof of water. Just because your mind is closed doesn't prove the issue is.

      --
      Learn to love Alaska
    2. Re:Tunnel vision by Anonymous Coward · · Score: 2, Informative

      "There is no proof that the water features were caused by water."

      Yes there is. There is no known other way to make complete delta systems with meandering channels and point bars, such as the ones found in Eberswalde Crater. It isn't the only example, but it is the clearest indication that at some times there was standing water on the surface of Mars. The only other possible explanation would be for some other liquid to be responsible, but it is very difficult to come up with an alternative that would make any sense. It certainly isn't the product of lava flows (no vents upstream, and the channels would have different geometries), and making liquid CO2 requires high pressures (supercritical fluid). What's left as an alternative? When you've eliminated all the alternative possibilities, the only thing left to conclude is that either you have a failure of imagination or the remaining hypothesis is correct: flowing water on the surface of Mars.

    3. Re:Tunnel vision by AK+Marc · · Score: 1

      Deduction, no matter how logical, is not proof. It is an inference or extrapolation, not proof.

      --
      Learn to love Alaska
  11. Gee, thanks! by Dan+East · · Score: 1

    Thanks a lot for raining on our parade.

    --
    Better known as 318230.
  12. Re:Good news by AK+Marc · · Score: 1

    We need to raise the mass to be able to hold an appropriate atmosphere. Slam large icy bodies into it, as well as anything else (ferrous ones and such) to get the mass as close to Earth as possible to make transition as easy as possible. Being further away, some extra greenhouse effect would be nice, so perhaps 1.2 Earth Mass units, and extra CO2 or methane or such. Especially if the extra iron masses don't melt to the core and start a magnetic field, we'll need extra atmosphere for radiation protection.

    --
    Learn to love Alaska
  13. Re:Good news by Third+Position · · Score: 1

    Or a large one, that appears to have a lot of the desirable materials that Mars lacks.

    Now we just need some genius to figure out how to get it to Mars.

    --
    American Third Position
    Finally, a real choice!
  14. moon a waste of energy by rubycodez · · Score: 1

    it is because of energy considerations a base on the moon is useless. you could make a huge spaceshp there, but where does the *fuel* for it come from? the only practical source of oxidizer there is water, and water is extrememly rare on the moon despite the recent hoopla about finding moisture at a level that makes the flour in your kitchen look wet.

    as long as we use chemical rockiets, the moon is a foolish stopping point or base.

    1. Re:moon a waste of energy by spauldo · · Score: 1

      There's tons of energy on the moon, if you're using solar and temperature differential sources.

      As far as getting your spaceship off the moon, you throw it, although you'd probably throw individual modules and assemble them in orbit. Fueling the spacecraft would be more complicated, but hey, it's a lot cheaper to launch a few tanks of rocket fuel into space from Earth than a whole spaceship.

      --
      Those who can't do, teach. Those who can't teach either, do tech support.
    2. Re:moon a waste of energy by yndrd1984 · · Score: 1

      moisture at a level that makes the flour in your kitchen look wet

      Flour is 10%-15% water, BTW.

      Besides, I'd assume we were going with nuclear engines/solar sails/ion drives once we "broke atmo".

  15. Re:Good news by rubycodez · · Score: 3, Interesting

    we don't have the means to increase Mars' mass by almost ten times! we can move mass on that scale, and the result would be an extremely hot molten mass that would take hundreds millions of years to cool off (your are essentially proposing the same process that formed the planets in the first place

  16. Re:Good news by AK+Marc · · Score: 1

    Slam the iron into it first, then when you want it cool, slam the ice into it. Yes, it will be hard and take a long time, but what other process would you do to make it livable? Activate the hidden alien console to melt the ice core?

    --
    Learn to love Alaska
  17. I always figured that the starting point..... by mark-t · · Score: 1

    ... for life on Mars came from the microorganisms that went along with the assorted probes and landers that we've sent there.

    --
    File under 'M' for 'Manic ranting'
  18. Re:Huh? by spauldo · · Score: 1

    Why is is that /. doesn't post stories of the 3,000 other scientific articles that suggest that Mars really was quite wet??!!

    The same reason the news doesn't announce that the sun comes up. Everyone knows about the evidence for water on Mars. This is interesting because someone came up with an alternate source for the clay formation that doesn't require water.

    Clearly there was once liquid water on Mars.... and a lot of it.

    Well, yes, there's a lot of evidence to support that, but this paper says the presence of clay soil doesn't necessarily count as evidence of water. No one's saying that there wasn't water on Mars - they're just saying you can't count the clay as evidence for a wet Mars.

    --
    Those who can't do, teach. Those who can't teach either, do tech support.
  19. Dig up the Fossils Already! by turgid · · Score: 1

    One of these days, when people finally get to Mars, they're going to wander over to one of those dried-up lake beds, dig with spades and find fossils by the thousand.

    You mark my words. I was right about Linux, I was right about NT4, I was right about itanic and I'll be right about this too. Just you wait and see.

    --
    Stick Men
  20. Re:Or, and here's a crazy idea... by jellomizer · · Score: 1

    Publish or parish.

    However even with the Mars Rover or even humans there... Science needs an Hypothesis and some plan of possibly testing for it. If we just assume Clay=Water. We see clay then we say there is water. We just test for clay. But if their is a Hypothesis that clay can form without water, There can be some differences you just may want to dig a little further and test out.

    --
    If something is so important that you feel the need to post it on the internet... It probably isn't that important.
  21. Re:Good news by rubycodez · · Score: 1

    haha, that's essentially how the earth formed and got its water. it'll take a long time alright, about 700 to 800 million years we already know