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Despite Clay Minerals, Early Mars Might Have Been Dry

timothy posted about 2 years ago | from the but-omg-mars dept.

Mars 105

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."

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Uh oh (0)

Anonymous Coward | about 2 years ago | (#41283383)

How will this affect my Mars Condo? Will Elon Musk still be my neighbor when I retire?

Or, and here's a crazy idea... (0)

Anonymous Coward | about 2 years ago | (#41283407)

...we could wait for new data from the Mars Rover which has been sent specifically to try and figure this shit out. Oh, but then we wouldn't get our papers published, would we?

Re:Or, and here's a crazy idea... (0)

Anonymous Coward | about 2 years ago | (#41284307)

its probably already stuck on a rock

Re:Or, and here's a crazy idea... (1)

jellomizer (103300) | about 2 years ago | (#41288509)

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.

Re:Or, and here's a crazy idea... (0)

Anonymous Coward | about 2 years ago | (#41289885)

Publish or parish.

That's a very parochial view.

Hmmm... (3, Interesting)

EddyGL (15300) | about 2 years ago | (#41283413)

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?

Re:Hmmm... (1)

jellomizer (103300) | about 2 years ago | (#41288525)

Volcanic activity?

Re:Hmmm... (0)

Anonymous Coward | about 2 years ago | (#41291343)

Volcanics [phys.org]

They keep changing the narrative.. (5, Informative)

tetrahedrassface (675645) | about 2 years ago | (#41283417)

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....

Re:They keep changing the narrative.. (2)

fsck1nhippies (2642761) | about 2 years ago | (#41283473)

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).

Re:They keep changing the narrative.. (4, Interesting)

ColdWetDog (752185) | about 2 years ago | (#41283861)

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.

Re:They keep changing the narrative.. (3, Interesting)

fsck1nhippies (2642761) | about 2 years ago | (#41284025)

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.

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41284631)

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.

Most of the enormous cost and risk is just getting things out of Earth's gravity well. If you're going to set up some sort of "interplanetary pit stop", orbit is still the best place. The Moon is significantly farther out (and much farther from resupply or rescue) with no really compelling economic or industrial reason to go there yet.

Even if you had a moon-base, we'd still need a good orbital one.

Re:They keep changing the narrative.. (1)

theshowmecanuck (703852) | about 2 years ago | (#41285005)

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.

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41288145)

You remember correctly.

It's easier (= less delta-v) to get from the surface of the moon to LEO than from the surface of the earth -- the latter is just as hard as from Phobos or Deimos [nss.org] . LEO to Mars requires half the delta-v of earth to LEO.

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41285229)

Err, the ISS is still in the Earth's "gravity well". That's why it's in orbit... The stupid ISS is about 400KM above the surface of the planet. The Earth's radius is 6400KM. So the ISS is 6.5% further away from the center of the Earth than you or I. Whooptee fucking thrill. Big big space outpost there. Frogs in free fall, yes sir.

And what the hell is the link to education, exactly? That's asinine.

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41285367)

Err, the ISS is still in the Earth's "gravity well". [...] So the ISS is 6.5% further away from the center of the Earth than you or I. Whooptee fucking thrill.

Technically the Earth's gravitational effects progress infinitely throughout the universe, if you want to continue being a douchebag about it.

Like I said, "orbit" as opposed to "the moon" is still a much better place. Perhaps not at LEO, but even out at geosynchronous orbits, the moon is still an order of magnitude farther away. Sure, it's easier to travel that distance, but you've still got the travel-time aspect to handle.

And what the hell is the link to education, exactly? That's asinine.

I suspect you are confused. I didn't say anything about "education".

Re:They keep changing the narrative.. (1)

HiThere (15173) | about 2 years ago | (#41289327)

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.

Re:They keep changing the narrative.. (1)

TFAFalcon (1839122) | about 2 years ago | (#41286135)

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.

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41289175)

Sure they may be slow, but if you aren't in a hurry they'll get you wherever you want.

Ion drives (and particle accelerator-type drives in general) aren't really that slow on the timescales on which interplanetary missions operate. Remember that a rocket can burn through all it's fuel in anything from less than a second to a few minutes (depending on the type) and coasts most of the way, while an ion drive catches up and speeds past at full power.

Re:They keep changing the narrative.. (1)

tetrahedrassface (675645) | about 2 years ago | (#41284685)

A big *amen* to both of you.

Re:They keep changing the narrative.. (1)

DerekLyons (302214) | about 2 years ago | (#41286777)

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.

Re:They keep changing the narrative.. (1)

CrimsonAvenger (580665) | about 2 years ago | (#41288411)

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....

Re:They keep changing the narrative.. (1)

DerekLyons (302214) | about 2 years ago | (#41288653)

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.

Re:They keep changing the narrative.. (4, Insightful)

Baloroth (2370816) | about 2 years ago | (#41284249)

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.

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41286047)

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

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

Mars has more gravity, too.

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

Re:They keep changing the narrative.. (1)

khallow (566160) | about 2 years ago | (#41286549)

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.

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41288223)

I think Zubrin is biased for a reason. I was also pro-Moon earlier.

The main problem with Moon is 1. lack of water and 2. you need a lot of energy to do anything on the Moon.
There's a LOT of water on Mars, and extracting it is a no brainer. On the Moon you need a lot more infrastructure for that.

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. What about heating? You'll be in the dark half the time and it gets pretty cold. The only option is nuclear reactors. Even more infrastructure needed.

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

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

Moon is a good option, but Mars is better for achieving self-sustainability.

Re:They keep changing the narrative.. (1)

theshowmecanuck (703852) | about 2 years ago | (#41284985)

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 [wikipedia.org] 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.

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41285417)

"Tell congress there are Arabs and Oil on Titan and there'll be 300,000 marines there inside a month."

There will be Indians there and since Americans can't tell the difference between a Sikh and an Arab....

Re:They keep changing the narrative.. (1)

Gripp (1969738) | about 2 years ago | (#41290141)

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.

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41283873)

I've no specific knowledge in the matter, but two major problems with a moon base spring to mind:

1) International law would probably make this difficult, nations aren't allowed to lay claim to territory on the moon, so you'd have to make it potentially open to all nations.

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.

Re:They keep changing the narrative.. (1)

bhcompy (1877290) | about 2 years ago | (#41284099)

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.

Re:They keep changing the narrative.. (4, Informative)

khallow (566160) | about 2 years ago | (#41284161)

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.

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41285433)

"1) International law would probably make this difficult, ..."

Like with torturing people, there are ways around this.

moon a waste of energy (1)

rubycodez (864176) | about 2 years ago | (#41284633)

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.

Re:moon a waste of energy (0)

Anonymous Coward | about 2 years ago | (#41285291)

And as long as F=ma and the Periodic Table of the Elements has no hidden magical materials, rockets are IT.

Re:moon a waste of energy (1)

spauldo (118058) | about 2 years ago | (#41285651)

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 [wikipedia.org] , 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.

Re:moon a waste of energy (1)

yndrd1984 (730475) | about 2 years ago | (#41286301)

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".

It's only natural. (1)

Anonymous Coward | about 2 years ago | (#41283539)

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

Re:They keep changing the narrative.. (1)

Anonymous Coward | about 2 years ago | (#41283813)

luna? You mean the moon, right?

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41286701)

I think he means that phone from nokia.

Re:They keep changing the narrative.. (0)

Anonymous Coward | about 2 years ago | (#41286195)

I thought that moon base as a stopover to mars idea was dead, since it costs way too much energy to get off the moon.

Re:They keep changing the narrative.. (1)

Chris Burke (6130) | about 2 years ago | (#41289211)

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.

Hmm (1, Interesting)

lightknight (213164) | about 2 years ago | (#41283445)

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.

Re:Hmm (1)

fsck1nhippies (2642761) | about 2 years ago | (#41283503)

It is even more interesting when you put a theological edge to it. Arks, floods, seclusion, new lands... You could also compare it to parasites jumping ship when they run out of resources.

Re:Hmm (2)

VortexCortex (1117377) | about 2 years ago | (#41283515)

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...

Re:Hmm (1)

Riddler Sensei (979333) | about 2 years ago | (#41283583)

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 [steampowered.com] .

Re:Hmm (2)

ColdWetDog (752185) | about 2 years ago | (#41283795)

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.

Re:Hmm (4, Insightful)

Third Position (1725934) | about 2 years ago | (#41284497)

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.

Re:Hmm (2)

spauldo (118058) | about 2 years ago | (#41285675)

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.

Re:Hmm (0)

Anonymous Coward | about 2 years ago | (#41289667)

Even the pyramids won't last that long.

Monuments are the wrong clue to look for. Food production is where it's at -- agriculture already takes up about 40% [fao.org] of our land surface.

The effect of fishing trawlers, to name one example, is such that it currently overshadows all natural processes in determining the distribution of new sedimentary layers on the ocean floor. A civilisation at our level of ecological impact would be geologically significant; a few goat herders not so much.

A biosphere, however, leaves its mark on a world.

I must respectfully disagree. While an advanced macroscopic surface biosphere would indeed be easily detectable, these [sciencemag.org] types of organisms would not. I would nevertheless argue that they are almost certainly extant on both our neighbouring planets.

Re:Hmm (1)

spauldo (118058) | about 2 years ago | (#41291515)

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.

Re:Hmm (0)

Anonymous Coward | about 2 years ago | (#41285977)

There is a matter of scale to take into account. Ancient civilisations of Earth were tiny by modern standards. The entire population of the planet from a few thousand years ago could fit into one modern city.

A spacefaring civilisation is a lot harder to miss. We make literally trillions of objects every year, large and small, durable or not, and for the civilisation to be noticed, only a single one has to be seen.

Re:Hmm (1)

Anonymous Coward | about 2 years ago | (#41286245)

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.

Re:Hmm (1)

khallow (566160) | about 2 years ago | (#41284261)

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?

Re:Hmm (1)

rubycodez (864176) | about 2 years ago | (#41284745)

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.

What about this? (3, Insightful)

RichardtheSmith (157470) | about 2 years ago | (#41283461)

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 [space.com]

Re:What about this? (3, Insightful)

cunniff (264218) | about 2 years ago | (#41283507)

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

Re:What about this? (4, Funny)

wbr1 (2538558) | about 2 years ago | (#41283511)

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

Re:What about this? (1)

zrbyte (1666979) | about 2 years ago | (#41283513)

Yeah. And what's with all the dried up [wikipedia.org] riverbeds? [space.com]

Re:What about this? (3, Interesting)

VortexCortex (1117377) | about 2 years ago | (#41283559)

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.

Re:What about this? (0)

Lord_of_the_nerf (895604) | about 2 years ago | (#41283787)

A magical deity did it. He did it in 7 days. Took a break in the middle.

It was an early beta, that's why he didn't let animals run around in it.

Re:What about this? (2)

nospam007 (722110) | about 2 years ago | (#41285443)

"How do you explain this without water? "

It used dehydrated water.

Buuut (-1)

Anonymous Coward | about 2 years ago | (#41283529)

Semi-intellegent huminoid life forms must be responsible for all climate changes. If the climate of mars is a barren desert now, it must have had once had water in the past and someone must be responsible for the change to current conditions. If it wasn't humanoid-like martians, who can be blamed? Climate can't be just changing on it's own, that wouldn't be politically correct...

Re:Buuut (0)

Anonymous Coward | about 2 years ago | (#41283963)

"Semi-intellegent huminoid"

You realize the only word you didn't misspell was "semi"?

No magnetosphere, no mass (4, Informative)

udachny (2454394) | about 2 years ago | (#41283589)

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.

Re:No magnetosphere, no mass (4, Informative)

spaceplanesfan (2120596) | about 2 years ago | (#41283911)

Titan [wikipedia.org] disagrees with you.

Re:No magnetosphere, no mass (-1)

Anonymous Coward | about 2 years ago | (#41284011)

Sure, now all we need to do is figure out how to live at -180C... Idiot Space Nutter moron fool.

Re:No magnetosphere, no mass (1, Informative)

udachny (2454394) | about 2 years ago | (#41284227)

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.

Re:No magnetosphere, no mass (1, Informative)

udachny (2454394) | about 2 years ago | (#41284245)

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

So does it still disagree with me?

Re:No magnetosphere, no mass (0)

Anonymous Coward | about 2 years ago | (#41290035)

Titan is right at the edge of Saturn's magnetosphere, and is sometimes outside of or otherwise have to deal with aspects of solar wind depending on the space weather conditions. Evidence suggest it has, and continues to lose large amounts of its atmosphere. The reasons it manages to still have one are likely to include its colder temperature, not just because it makes the gases easier to hold onto, but also because it makes it easier to have reservoirs of solidified components of the atmosphere on the surface to resupply the atmosphere.

Of course a planet like Mars couldn't sustain an atmosphere, but the question is over what timescale could it maintain a "transient" one... which could be quite a long time depending on how much source material it had stored up on the surface initially.

Re:No magnetosphere, no mass (0)

Anonymous Coward | about 2 years ago | (#41289741)

titan is an example of gas torus.

Re:No magnetosphere, no mass (1)

Third Position (1725934) | about 2 years ago | (#41284545)

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.

Re:No magnetosphere, no mass (1)

rossdee (243626) | about 2 years ago | (#41284719)

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

Re:No magnetosphere, no mass (1)

Convector (897502) | about 2 years ago | (#41285029)

While there is no global magnetic field today, strong crustal magnetism [sciencemag.org] 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.

Re:No magnetosphere, no mass (0)

Anonymous Coward | about 2 years ago | (#41285425)

he's right (Original poster)

They have workarounds for it though... such as Domes etc..

Also look into the affects of deliberately inducing the greenhouse affect --- You may find it will support life (of the human variety).

Dry? (1)

slick7 (1703596) | about 2 years ago | (#41283637)

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

Re:Dry? (2)

Lord_of_the_nerf (895604) | about 2 years ago | (#41283775)

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

Re:Dry? (1)

Sulphur (1548251) | about 2 years ago | (#41283831)

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.

Paper far from disproving wet Mars (0)

Anonymous Coward | about 2 years ago | (#41283707)

While the researchers claim to have some interesting insights, there is other overwhelming evidence that Mars did in fact have lots of water concentrated in lakes and rivers in the past. How do we know that? How about the fact that we can see them [arizona.edu] from orbit? Or that we see river deltas [wikimedia.org] .

Re:Paper far from disproving wet Mars (1)

Anonymous Coward | about 2 years ago | (#41283771)

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.

But what about K'breel and friends? (1)

Alex Belits (437) | about 2 years ago | (#41283967)

Without water they wouldn't have gelsacs!

Mars Data Already Known (0)

Anonymous Coward | about 2 years ago | (#41283981)

Everything you need to know about Mars has already been written by L. Ron Hubbard. Just join the Church of Scientology and for about $500,000 you can learn all about it. Either that, or read this website:
http://www.xenu.net/archive/multimedia.html

Once the page is loaded just search for the keyword "Mars".

Tunnel vision (5, Insightful)

Grayhand (2610049) | about 2 years ago | (#41284009)

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?

Re:Tunnel vision (4, Interesting)

AK Marc (707885) | about 2 years ago | (#41284447)

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.

Re:Tunnel vision (2, Informative)

Anonymous Coward | about 2 years ago | (#41286111)

"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 [wikipedia.org] . 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.

Re:Tunnel vision (0)

Anonymous Coward | about 2 years ago | (#41286117)

Oh, I did think of one other possible liquid: liquid methane, which is thought to have carved river channels on Titan. Unless Mars was once much further from the Sun, that one doesn't make sense either (it would be too warm).

Gee, thanks! (1)

Dan East (318230) | about 2 years ago | (#41284221)

Thanks a lot for raining on our parade.

Good news (0)

Anonymous Coward | about 2 years ago | (#41284335)

The sooner we can conclude that Mars is and has always been sterile, the sooner we can start the terra forming process. Step 1 will be smashing a large number of icy small bodies into Mars.

Re:Good news (1)

AK Marc (707885) | about 2 years ago | (#41284473)

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.

Re:Good news (3, Interesting)

rubycodez (864176) | about 2 years ago | (#41284657)

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

Re:Good news (1)

AK Marc (707885) | about 2 years ago | (#41284819)

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?

Re:Good news (0)

Anonymous Coward | about 2 years ago | (#41291723)

Slam politicians, bankers and lawyers first!

Re:Good news (0)

Anonymous Coward | about 2 years ago | (#41293109)

The mass of every rocky body in the inner solar system would be barely enough to construct a second Earth (assuming you're leaving Earth intact). Most of this matter is in Venus (0.815 Earth mass). Mercury + Mars amount to another 0.162 Earth mass. Throw in the moon at 0.0123 to cap it off, and what you have is roughly 99% of Earth's mass. The asteroid belt is a rounding error at 0.0005 Earth mass total.

Once you get the technology to move planetary-sized masses around, it would probably be more practical to just toss Mars away and put Venus in Mars's current orbit or a bit further out. The thick CO2 atmosphere will keep it nice and warm. No need to collide anything into it.

Re:Good news (1)

Third Position (1725934) | about 2 years ago | (#41284591)

Or a large one [wikipedia.org] , 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.

Huh? (0)

Anonymous Coward | about 2 years ago | (#41284449)

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

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

Unfortunately, the source publication isn't even available yet, and even then it will be pay-walled.

Re:Huh? (1)

spauldo (118058) | about 2 years ago | (#41285743)

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.

I always figured that the starting point..... (1)

mark-t (151149) | about 2 years ago | (#41285099)

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

Dig up the Fossils Already! (1)

turgid (580780) | about 2 years ago | (#41285963)

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.

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