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Mars Images Reveal Evidence of Ancient Lakes
Matt_dk writes "Spectacular satellite images suggest that Mars was warm enough to sustain lakes three billion years ago, a period that was previously thought to be too cold and arid to sustain water on the surface, according to research published today in the journal Geology. Earlier research had suggested that Mars had a warm and wet early history but that between 4 billion and 3.8 billion years ago, before the Hesperian Epoch, the planet lost most of its atmosphere and became cold and dry. In the new study, the researchers analysed detailed images from NASA’s Mars Reconnaissance Orbiter, which is currently circling the red planet, and concluded that there were later episodes where Mars experienced warm and wet periods."
Until we go there and see. Interesting idea though.
"If you want to know what happens to you when you die, go look at some dead stuff."
Your ex is over 3 billion years old? That must have chafed..
which is totally what she said
Europa may well be warm and wet under the layer of ice. In fact Europa probably is, and might in fact harbor life. Can we please forget about Mars? Mars sucks because we keep going there and not really finding anything of importance. I am tired of Mars, there are other, more interesting places to explore.
What proof would satisfy you?
Tesla was a genius. Edison however was a overrated hack who liked to torture puppies.
What is so special about humans manipulating measuring equipment versus robots? This notion that we must send people into space is just romantic.
Wow, you seem terribly defensive over what is a pretty reasonable question. This is slashdot, you are allowed to ask things here...
Anyways, from what I understand (and this is in no way my field), they usually date these sorts of things by observing what kind of geological features are on top. If a crater has numerous smaller craters in it, then you know the larger crater is older. With the crater distribution they can make pretty reasonable estimates about the age of something. Similar methods techniques could use other forms of erosion.
Dating like this obviously isn't exact, and you'd have to ask a geologist for more details on the accuracy and techniques. For that matter, I haven't read TFA so I don't know that this is exactly how it was done. If you are really curious, I suggest you RTFA, and read any papers these scientists have/will release on their findings.
"linux is just DOS with a UNIX like syntax" -- Galactic Dominator (944134)
So would 'global warming' have prevented this type of disaster?
Um questioning science honestly is something people like. Denying science or questioning science via misinformation would make you a heretic.
The article does address this:
"The researchers determined the age of the lakes by counting crater impacts, a method originally developed by NASA scientists to determine the age of geological features on the moon. More craters around a geological feature indicate that an area is older than a region with fewer meteorite impacts. In the study, the scientists counted more than 35,000 crater impacts in the region around the lakes, and determined that the lakes formed approximately three billion years ago. The scientists are unsure how long the warm and wet periods lasted during the Hesperian epoch or how long the lakes sustained liquid water in them."
The researchers determined the age of the lakes by counting crater impacts, a method originally developed by NASA scientists to determine the age of geological features on the moon. More craters around a geological feature indicate that an area is older than a region with fewer meteorite impacts. In the study, the scientists counted more than 35,000 crater impacts in the region around the lakes, and determined that the lakes formed approximately three billion years ago. The scientists are unsure how long the warm and wet periods lasted during the Hesperian epoch or how long the lakes sustained liquid water in them.
So to answer your question the moon is the reference point.
It has large error bars, but it's the best we have until we can send radiometric dating to these areas. [Crater Counting]
Contrary to what the "internet" likes to tell you, many people question what scientists say because they want to see actual proof to support the claims rather than just additional layers of theories and educated "guesses".
And the people who are legitimately intellectually curious rather than simply delighting in taking jabs at the "scientific orthodoxy" don't universally phrase their questions as "Do you know what you're talking about or are you making shit up that supports your preconceived notions?"
"How do they determine those dates?" is a fine question, one I am curious about as well. "Gee, in the scientific method I'm used to, you have to have a known reference. Do they have one? Have they been following the scientific method?" kinda makes you sound like the kind of person you are implying you aren't. Maybe you're just being defensive, or using modding reverse-psychology. But really, just leave that part out.
The enemies of Democracy are
This question got modded as insightful? I think the poster should have to read the article before having comments modded as insightful. From the article: > The researchers determined the age of the lakes by counting crater impacts They don't go into a lot more detail than that -- it's not a scientific paper -- but that at least answers your first question. Asking for more details is reasonable but asking those questions actually requires some effort. Questioning scientists intelligently is more than just speculating about their possible failures without reading what they've said.
But what have you done for us LATELY?
SJW: Someone who has run out of real oppression, and has to fake it.
The surrounding area may be quite old based on the crater count but it seems that the "lakes" must have come a some later time as they do not show any impacts. Does this make sense?
You must be new here... ;)
Unfortunately, not reading TFA is pretty par for the course here. Comments like this get modded up because often the moderators haven't RTFA either. "Playing a martyr to get easy modpoints" seems to be getting pretty popular as well. (note: I'm not accusing the GP of karma whoring... at least intentionally)
"linux is just DOS with a UNIX like syntax" -- Galactic Dominator (944134)
Continuing off topic...
Your post reminds me of the day a coworker came into my office with a look of deep thought on her face, asking why we need to use money. Not getting where she was going, I started explaining that money is just an accounting system. That didn't satisfy her, so I started to explain how it evolved from barter.
She stopped me, and saying that she understood that, followed by a but "Why can't we just go to work, and when we need something just go to the store and get it? Why do we need to keep track of it with money? That's what I think we should do."
At that point I got what she meant, and told her that theoretically we could. And said "What you are describing is communism." She then puffed up and angrily said "YOU are a communist." and stomped out.
Probably more like Venus
Sure, but "Denying science" is defined by many as not taking a popularly believed theory at face value even when there is evidence to the contrary. And "misinformation" is defined by many as any evidence or questions that don't fully support the theories they have taken as fact.
How are these dates determined?
Basically, they're counting craters.
The idea is that everything in the solar system is being steadily bombarded by random bits of debris. More craters means that something has been exposed to the elements for a longer amount of time.
In this case... If you have a once-lakebed that's now covered with craters, it must have been a while since there was water in it.
No, it isn't perfect. But it isn't too horrible either.
And, of course, the numbers will be refined as more/better data and measurements become available.
"Work is the curse of the drinking classes." -Oscar Wilde
any effort to seed the martian atmosphere would at best be a temporary(ok, a few million years) improvement. Mars lacks the gravity to hold the atmosphere. what's more, the warmer the atmostphere the faster it will disipate off into space.
in the 3 billion years since the lakes existed, mars has reached an equilbrium.
Sorry to post off topic to your sig, but universal helthcare is socialist. whether or not it is a good thing remains to be seen.
NO. It's a social program, but it not socialist. Unless you consider the police, army, judicial system and public schools also to be socialist.
Socialism is very different than social programs.
Tesla was a genius. Edison however was a overrated hack who liked to torture puppies.
What is so special about humans manipulating measuring equipment versus robots? This notion that we must send people into space is just romantic.
The romanticism of the adventure is one of the strongest motivators of exploration. Take that away, and it's just work.
Besides, there are practical reasons for sending humans into space. One day, in order for the human species to survive, we will have to move off this rock and travel to other regions of our galaxy. We might as well start our baby steps now.
It is Government-run healthcare that is intrinsically oppressive and untenable to freedom loving peoples.
Just like a government run judicial system and military forces.
Tesla was a genius. Edison however was a overrated hack who liked to torture puppies.
I'm probably going to get modded down or flamed for being a heretic for daring to question modern scientific orthodoxy
Ah, the classic cry of the rebel without a clue.
Listen up, kid: you are not an iconoclast. You are not boldly speaking truth to power. You are not Martin Luther nailing his theses to the cathedral door. You are not a special snowflake.
Everyone who has ever worked in this project has thought of, and answered, every single one of your questions long ago. And those answers are easily available with a small amount of digging, which you would do if you had any interest in the actual answers instead of just self-aggrandizing puffery.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
the photo shows liquid exchange between craters. Couldn't this be something apart from water?
So, the aliens have successfully stolen all of the water from Mars (as reported in thousands of lousy science fiction movies and TV dramas). Is the Earth next on their list of planets to steal the water from? I mean, it's not like you could possibly manufacture your own water by taking a couple of common elements in the universe, like hydrogen and oxygen, and combine them using a stupid trick like fire.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
Our ancestors were the original inhabitants of the Red Planet who seeded life here after determining their home world was doomed to destruction (massive asteroid impact is my guess).
Sorry, too much Clarke and Heinlein as a kid I suppose.
/. Dissent will not be tolerated. Think like us or perish.
Where was the last place you saw it? You must have lost it somewhere between here and there. Don't forget to check under the sofa cusions.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
It has large error bars, but it's the best we have until we can send radiometric dating to these areas. [Crater Counting]
If you'd like a somewhat more detailed explanation, try Dr. Hartmann and Herres six year old explanation at:
http://www.psi.edu/projects/mgs/cratering.html
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
any effort to seed the martian atmosphere would at best be a temporary(ok, a few million years) improvement.
A few million years would, of course, be more than enough time (by a factor of 10000 or so) for colonies to flourish and grow. And presumably, if we figured out a technique that we could use to do it once, our many-times-great-grandchildren could repeat the process if the air started to get a little thin.
Mars lacks the gravity to hold the atmosphere.
Okay, here's something I've always wondered about: Venus has a surface gravity of about 0.9g, yet manages to hold on to an atmosphere over ninety times denser than Earth's (and it does this closer to the Sun, too.) So while there's clearly an upper limit to the atmospheric density a planet with a given surface gravity can maintain, Venus suggests to me that Earth is nowhere near this limit ... and that Mars with an Earthlike atmosphere wouldn't be either. Am I missing something?
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
Nope, just another philosophy major on the Internet
Faster! Faster! Faster would be better!
The Earth's magnetic field protects the atmosphere to some extent, and Mars and Venus don't have much of one. Venus has lost most of its original water (or rather the hydrogen that was in the water) to space.
a,e,i,o,u and sometimes w and y (at be if of up cwm by)
Lost its water, sure, but not the rest of its atmosphere. What I'm wondering about is the overall mass and density of the atmosphere which a planet of a given size can maintain, and again, based on the example of Venus, it seems like neither Earth nor Mars can be anywhere near the upper limits for those numbers.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
As a Canadian, I have to quirk my eyebrow at that.
You realize that we have supplementary coverage up here, right? Hear me out.
The government provides basic health coverage. They cover almost everything, from emergency treatment to birth and annual physicals.
We don't get coverage for private rooms, eyeglasses, Rx medication (unless you spend $3k a year or more, long story), massage, physio, etc. There's a long laundry list of things that aren't covered. Ambulance rides aren't covered, but that's because too many people were using it as a taxi service. It's $65, but when you need one, it's money well spent.
I can go out and buy more coverage. My wife gets Green Shield from work, and that covers $250 in eyeglasses every 2 years, massage and physio, 80% reimbursment on medication, private rooms, dental care, etc. I have an HSA at work, but I use my wife's plan instead because it's a better plan.
When my kids were born, it cost me $12 for parking each time. When they got hit by a car and rushed to the hospital, it cost me $10 for dinner and $65 for the ambulance. (For each of the above, there were multiple ultrasounds, xrays, blood tests, beds, bandages, etc.) That's all I had to pay.
When it's critical, there aren't wait times, despite what you may have heard. My friend had a sharp pain in his head when he coughed -- he was ushered in right away, had an ultrasound, a CT scan, and a spinal tap within 30 minutes of arriving at the hospital. (The wait was because someone was in the machine.)
I was having chest pains about six months ago, so I went to a drop-in clinic (not my regular GP) and had an ECG within about 15 minutes.
This is all stuff that's just covered up here, and always has been. True, the system has faults, but that's because our politicians up here get really good secondary coverage so they don't feel any pain from cutting back on health care spending. (These are the same breed of jokers that brought Canada from the 3rd largest Navy in the world at the end of WW2 to the 3rd-div team it is today.) If they increased health-care funding, we'd be in much better shape and the Americans would have nothing to point their fingers at.
By the way, my tax rate was ~15% in 2008. I haven't done my 2009 taxes yet. (It's not a directly fair comparison because we also have subsidized education up here -- my engineering degree cost me ~$0 net.)
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ECHELON is a government program to find words like bomb, jihad, plutonium, assassinate, and anarchy.
No, you're not missing anything. The "not enough gravity" explanation is completely bogus. Titan is a lot smaller than Mars, hell it's only half as massive as Mercury, and holds on to an atmosphere with a surface pressure 50% greater than earth. In fact, the atmosphere is so thick and the gravity so low, that a human could strap on a pair of wings and easily flap their way to self-powered flight.
The real culprit behind Mars' lack of atmosphere is twofold.
1. no magnetific field
2. the sun
The Solar wind is not being defelected by a magnetic field, so it's slowly been stripping away the atmosphere for a couple billion years, a little bit at a time.
With some localized global warming, there may be enough water ice trapped under Mars' surface to start chainreaction greenhouse effect. Get some Water Vapor and C02 into the atmosphere, warm up the planet a few degrees, get some more melting/released from under rocks, until it's all up there and we've got a workable atmosphere around the planet. As another poster pointed out, you DO eventually lose that atmosphere for the same reason Mars lost it's original atmosphere, and you won't be able to replace it the same way as you've already used up that resource... BUT, you don't have to use the same method. I'd think that with a couple million years (realistically, more like a couple hundred years at the rate our technology advances), Human beings would have figured out how to manipulate asteroids and comets on a molecular level, and be diverting some asteroid belt and kuiper belt objects towards mars to replenish the atmosphere from time to time.
Adding CO2 and water to Mars is going to involve industry. And energy. Shitloads of both. Industry is going to involve, by necessity, many of the chemicals you mention, either to run the machinery or as a byproduct of it. Therein lies the problem. Mankind isn't going to wait around for hundreds of years for a long, slow, low-energy terraforming system to work, so by the time we've turned the dial to 11 for enough years to have reached a semi-breathable atmosphere, it'll be polluted.
Now add in your comment about "maintaining our lifestyle". If you typed your post on a computer while wearing clothing in an enclosed space with heat, congratulations, that requires all the chemicals you mentioned above and more.
Even if the Earth's population stopped growing right now, we likely cannot maintain the lifestyle we enjoy now in the US and Europe, and there'd be no way in hell we can extend that same lifestyle to the rest of the planet. Add in the resources necessary to start terraforming Mars and the time it will take for it to complete, and we'll be loading Mars up with more people than it can sustain during the entire process. As soon as Mars has an atmosphere that can grow a few crops and support 50,000 people, we'll dump a half million there in the false hope it'll relieve the population pressures on Earth. And both planets will be overpopulated continuously until we figure out how to overpopulate another planet.
Robinson's "Mars" series, mentioned in the post you replied to, is an excellent read. Robinson has an interesting and thoughtful, if just a tad hopelessly optimistic at the end, view of how terraforming might play out. It's a relatively well-researched (or seemingly so) series, with a lot of interesting theories on approaches to terraforming, and plays out a very human approach to it.
"This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
And here again you prove the anti-healthcare arguments. You're healthcare is up to the whims of a politician. Compared to how it should be, I buy the amount of healthcare I want. Something we mostly don't have in the US but should be working towards not away from.
Paying taxes to buy civilization is like paying a hooker to buy love.
its no more socialist than the police force is, even if you never need to use haelthcare (which is extremely unlikely) most rational people are happy to contribute in case they do need it.
at least thats how it works over here in europe.
There are many first world countries with universal healthcare. Why are they not good examples of the effects? I am not arguing for or against. I simply stating that countries like Canada and Germany can serve as examples.
Space Shuttle was a program that strapped humans to an explosion and tried to stab through the sky with fire and math
"Channel connecting depressions in bottom right providing clear evidence of liquid exchange between depressions."
Around here, we call that a "river"... XD Most lakes have one or two connecting them to other bodies of water.
"Convictions are more dangerous enemies of truth than lies."
Mars once had a much thicker atmosphere, so it must have gone somewhere. A mechanism for its loss to space has been proposed, but this is not settled science. Still, there is no obvious place on the planet for most of the old atmosphere, presumably mostly carbon dioxide, to be sequestered (carbonates or what not).
a,e,i,o,u and sometimes w and y (at be if of up cwm by)
I agree, it's not because you have an engineering degree that you know so much about something that you have never had contact with, as well they are using earth type examples to template off of, thinking there could never be any similar thing that would cause water like patterns in the sand, so it must be water, what about liquid gasses...they are liquid too, but not water...anyways, I lost interest in what they were doing a long time ago....when I saw some of the presumptions they made about so many space things. Try asking about dark matter!
And it's fantastic! Healthcare is a major election issue. Politicians are spineless attention seekers who will do anything to get elected. You can't get elected on a platform of reducing healthcare, and every election cycle the opposition parties pick apart the performance of the health system and loudly promise to improve it. Then whoever is elected sets the health budget at the lowest they think they can get away with and lets the doctors get on with it. The doctors routinely overspend because they won't refuse necessary treatment, and then the new opposition parties complain about the budget shortfall and any shortcomings at the next election.
The system is very focused on the best outcome for the lowest cost which is a much better climate for preventative medicine.
Compare that to private health insurance, where a bean counter will approve as little care as will keep them from getting sued, and I'll take it any day.
.evom ton seod gis eht
...aaaaaaand...now we're safe from terror...
Don't forget: Firemen - The Red Truck Menace!
There is a war going on for your mind.
In the long term, iceteroids in the outer solar system seem to be a reasonable source of replacement hydrogen and oxygen for a terraformed Mars.
The nice thing about them is that, assuming you have nuclear rockets of sufficient size and durability, an asteroid made of ice is essentially made of reaction mass.
Other places you could get hydrogen (or water - strip out the oxygen if you don't want it) include the gas giants themselves or some of their satellites. The inner Jovian moons are unlikely to have significant human habitation because of high radiation levels, but an automated ice-mining operation on Europa, say, isn't out of the realms of possibility.
Assuming we don't get a large black monolith sending us warnings not to land there, of course :)
Yes, all of this is well out of the realms of current engineering capabilities. But there doesn't seem to any fundamental reason why it's impossible.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
That was my point. In Canada, you buy whatever coverage you want. If you can't afford any, you get a base coverage of medically required procedures.
To summarize Canuck Health Care:
1. The basics are paid for.
2. You can buy more insurance.
That's all there is to it. If you don't make enough money, you get taken care of. If you make enough, you get the same care for the same price*, but you can buy more. I can get coverage that'll cover a massage every day and chocolate mints on the pillows in a private suite in the Mayo Clinic.
*Some provinces, like BC, have extra MSP premiums. I pay ~$100 a month for a family of four.** If the household income was less than about $35k, then the premiums would be waived. Where this differs from regular (i.e. American) insurance is that I cannot be retroactively denied coverage. (Post-claim underwriting, I think you call it.) Also, if I don't pay, my coverage doesn't lapse.
**This is actually paid via my wife's supplementary coverage from work.
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ECHELON is a government program to find words like bomb, jihad, plutonium, assassinate, and anarchy.
I wondered about that as I was posting. Where would we get all this water and CO2 from? We can't really export it from Earth because that'll fuck up our ecology here.
We'd have to make it on site once we get to Mars, and that means industry, like you say. I've never had a problem with industry -- I like the fact that I don't have to spend all day every day growing / chasing food and finding water. You're conflating environmentalism with Ludditism. Technology and industry are fantastic. However, we can be more responsible with wastes this time around. We know we can't dump industrial waste into the ocean and have it magically disappear. (Fire it into space! ;) )
Red Mars is on my list, but I can only read so many books at a time. (It's bought, on my shelf, and ready to go.)
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ECHELON is a government program to find words like bomb, jihad, plutonium, assassinate, and anarchy.
That is what they are. Educated guesses. The scientist gets some information and builds a consensus on a rough time frame. They could be off by a million years but close enough when you are talking billion years. Carbon dating probably couldn't work either because of the differences in atmosphere. It would be cool to send humans to Mars to say we did it and bring back tangible proof like we did for the moon in the 60's. NASA has been wasting alot of money on the shuttle these days and needs to get the next vehicle ready now. Relying on the Russians to transit to and from the ISS is inexcusable for this country. Then on to the moon and build a station on the moon. At first unmanned but eventually setup to be manned like we currently do with the ISS. The only issues would be meteor strikes or significant failure that would prevent astronauts from escaping if there was a life threatening issue.
A) Most people question scientists because the conclusion from studies are different them the sacred cows.
B) Most people wouldn't understand the data
C) " based on supposition to support a hypothesis?" this seldom lasts long.
D) Your question are all good one, the type of questions a 5 year old asks. That's not an insult, 5 year olds ask the best questions.
Unlike a 5 eyar old, you could easily get the answers to those question, so I won't hold your hand.
The Kruger Dunning explains most post on
Aha! No, you want room 12A, next door.
Mars has frozen water at its north pole and possibly subterranean aquifers that can be brought to the surface with shaped nukes. Diverting comets is a way to add water to the atmosphere. Again, read KSR's trilogy, it's well-researched.
If my choice is health care up to the whims of a politician or up the whims of an insurance executive I'll choose the politician.
If you read my other response, I'm suggesting that the dates are not based on anything other than a very limited time period of observation and scientists have extrapolated from that limited data set a rate of impacts. They then used that to provide an educated guess on the age.
The problem with this is that is is very likely to be as accurate as a random guess. It has no basis in "fact".
Jesus was a compassionate social conservative who called individuals to sin no more.
I'd much rather have health care up to my health care provider, and health insurance up to my insurance provider. Why should I be required to have maintenance and insurance in the same policy? It's these bundlings that really cause faults with any system.
Paying taxes to buy civilization is like paying a hooker to buy love.
Kind of right I guess. Although it's not as much of a misnomer as calling the US's current system Capitalist.
Paying taxes to buy civilization is like paying a hooker to buy love.