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Mars Images Reveal Evidence of Ancient Lakes

timothy posted more than 4 years ago | from the older-I-get-the-wetter-mars-was dept.

Mars 128

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."

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Yeah (-1, Flamebait)

Anonymous Coward | more than 4 years ago | (#30655424)

but how is dis gonna help get me my free healthcare?

Re:Yeah (-1, Flamebait)

Anonymous Coward | more than 4 years ago | (#30655554)

We're gonna drown all the free-loading niggers in it and so the costs will go down dramatically once the welfare queens are dead.

Ohh so (0)

Anonymous Coward | more than 4 years ago | (#30655426)

Mars is just like my ex?

Re:Ohh so (2, Funny)

somersault (912633) | more than 4 years ago | (#30655448)

Your ex is over 3 billion years old? That must have chafed..

Re:Ohh so (0)

BESTouff (531293) | more than 4 years ago | (#30656770)

Don't think so. But maybe the Earth will be like Mars once we have completed our "pollute-everything-you-can" task.

Re:Ohh so (1)

Alphathon (1634555) | more than 4 years ago | (#30656864)

Probably more like Venus

Re:Ohh so (0)

CRCulver (715279) | more than 4 years ago | (#30656904)

Don't think so. But maybe the Earth will be like Mars once we have completed our "pollute-everything-you-can" task.

Or Mars will become more like the Earth once terraforming is initiated, even if it's just local changes under domes instead of the complete transformation of the planet portrayed in science-fiction like Kim Stanley Robinson's Red Mars [amazon.com] . Now we can present to environmentalist-minding people a conundrum: what's better, an arid lifeless planet, or a planet that's polluted but life-sustaining?

Re:Ohh so (0)

Beardo the Bearded (321478) | more than 4 years ago | (#30658420)

I'd prefer a non-polluted life-sustaining planet.

I am an environmentalist, but I don't think that we have to live in caves and grow our own food to keep Mother Gaia and all Her Creatures in something something, I kind of lose interest at that point too.

If you consider terraforming pollution, then you and I have different views. Adding carbon dioxide and water to Mars to make it habitable for humans is perfectly acceptable. We require more earths to sustain our lifestyle, and we've only got the one tiny little blue marble.

Adding CFCs, tetraflourohexine, formaldehide, PCBs, and any other alphabet-soup materials to a new planet is something completely different. Now that we know better, we can be responsible with our materials handling and stop shitting where we eat.

Re:Ohh so (2, Insightful)

natehoy (1608657) | more than 4 years ago | (#30658946)

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.

We'll Never Know For Sure (2, Insightful)

Dr_Ken (1163339) | more than 4 years ago | (#30655432)

Until we go there and see. Interesting idea though.

Re:We'll Never Know For Sure (5, Interesting)

carlhaagen (1021273) | more than 4 years ago | (#30655558)

The images speak pretty clearly for themselves, and have done so for a long time. We already know since forever what formations liquid deposits create over time on malleable surfaces.

Why? (1)

sidragon.net (1238654) | more than 4 years ago | (#30656056)

What is so special about humans manipulating measuring equipment versus robots? This notion that we must send people into space is just romantic.

Re:Why? (0)

Anonymous Coward | more than 4 years ago | (#30656254)

We need to bring back rocks, And if your going to send enough fuel to get off the surface, why not take a person along for the ride. Besides robots can't play golf

Re:Why? (1)

natehoy (1608657) | more than 4 years ago | (#30659166)

Because a robot can be powered down and require no resources for the flight there and back. They can also be stacked neatly into boxes. They also don't fight, or make little robots. They can stay at Mars forever, and no one will clamor to bring them back to Earth. And if your measurements are off and you kill one, you send another.

Heck, you could fit Spirit, Opportunity, and probably a few hundred similar robots in the same amount of space and weight you'd need to provide a single human with food, water, and entertainment for the multi-year mission. And you'd get a LOT more science done. And there'd be plenty of space for an unmanned return module to bring hundreds of pounds of samples back.

If your mission is to learn as much as possible about Mars, sending a human there is about the worst way you could go about it. You're going to stand a good chance of killing him/her, and the space and mass they take up will hobble your eventual effort into near-uselessness. They won't be able to stay for long, and most of your ship will need to come back in order to support them, which means you need a LOT of fuel.

There's certainly the romantic/endeavor angle, and that can't be discounted. But if you really want to inspire people about space exploration, let's build a base on the Moon. With the lower gravity well, it would make a fantastic platform to launch a robotic mission to Mars, and would teach us a lot of lessons about living long-term in the kind of conditions an eventual Mars manned mission would experience. Think "Biodome" without the opportunity to sneak in candy bars.

Better yet, build a permanent, self-sustaining space station at a Lagrange point. If we can do that and keep it running for a decade without outside support, we are ready to send a ship to Mars and keep people there for a while. Maybe even make it a one-way trip and make the ship a space station that can become a permanent orbital settlement over Mars, as a base to start the terraforming process.

Re:Why? (1)

shurikt (734896) | more than 4 years ago | (#30660320)

Because a robot can be powered down and require no resources for the flight there and back. They can also be stacked neatly into boxes. They also don't fight, or make little robots. They can stay at Mars forever, and no one will clamor to bring them back to Earth. And if your measurements are off and you kill one, you send another.

Which is really suboptimal, because it takes a lot less cost to manufacture humans.

Re:Why? (0)

Anonymous Coward | more than 4 years ago | (#30656660)

And what is wrong with wanting to send people into space? When you take a vacation from work, why do you travel? You could stay home and look at pictures of the places that you want to see. It is human nature to want to explore and do it first hand. It is the same reason that people climb Everest, go to the north or south pole, dive deeper & deeper into the oceans and travel to all the most remote locations on the earth. Yes, we could just send robotic planes & subs to those locations, but then we would miss out on so much. I think that the day that the human race loses that urge to explore what is around the next corner is the day that the human race will start the decline to extinction.

Without romanticism exploration will stagnate (1)

dragmyfeet (1712972) | more than 4 years ago | (#30657478)

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.

Re:Why? (2, Insightful)

khallow (566160) | more than 4 years ago | (#30658020)

What is so special about humans manipulating measuring equipment versus robots?

We do it better.

Re:Why? (1, Insightful)

Anonymous Coward | more than 4 years ago | (#30658082)

Because people can wander around navigating the terrain a lot better and quicker. Now imagine the person is in fact a geologist. They can immediate analyze what they are seeing, move around looking for interesting things, all the time E.g. "Ooh, that's an interesting rock". WHACK. "Hmm, look at that...". Now compare that to an incredibly slow robot that has to inch around, take a picture, send data home, have it processed here, wait, wait, wait. Experts here decide to move the robot 2 feet to the left. wait wait... Robots can't jump into craters or climb hills without massive planning, analysis and Earth based simulations. That takes weeks. Geo Joe can just wander off and start his science work.

Re:Why? (3, Informative)

natehoy (1608657) | more than 4 years ago | (#30659652)

The limitations of our current robots were based on space, cost, and durability. A geologist might be able to search the terrain faster, but they won't be able to be there for more than a few days or weeks at best, and each geologist could really only search one general area. In the same space as your single geologist and all the food and resources he/she will need, we could explore multiple places on the surface of Mars with a generous handful of Spirit-type robots, and they could all stay there for years collecting data.

The reason Spirit and Opportunity are so slow is because they operate on a small solar array, that generates (at peak) 140 watts for the 4 hours of daylight they get in a Martian day. That's about 560 watt/hours an m-day at best, and that's all the energy they need to do what they do. That's a lot of science packed into that amount of energy. They are currently getting a fraction of that due to dust on the arrays, and yet they are still collecting good science, six years in.

If you want enough energy to support a human being there, you're talking nuclear engines. If you're going to make that kind of energy available, you might as well power the robots with nukes - they will then be able to move faster than a human could, and there could be hordes of them for the same cost and resources expended sending one human. And they could stay for years.

To get a single human to mars, on the surface, and back to Earth, you'll need about a half ton of dehydrated food, enough water to recycle so they have a continuous supply, and probably a few thousand watt-hours a day minimum for the entire trip for heat, light, etc. You'll also need radiation shielding (likely tons of it) for the multi-year trip, room for them to exercise, many tons of fuel for the two-way trip, etc.

Spirit weighs about 400 pounds, or a little over twice the weight of a human. But you save the half-ton of food, the water, more than half the fuel (no return trip, no need to re-orbit it), and almost all the energy needed to sustain life during the voyage. The ship is simpler, since you need almost no shielding, no living space - just strap a few (or a few hundred) robots around the outside of a rocket engine.

Take a science team of a dozen, and you could probably have at least 50, maybe 100 robots take their place. And those robots would be able to work there for years. Each could have its own nuclear plant and probably have power and functioning instruments for decades (energy starvation from the solar cells is what is slowly killing off the current robots).

Plus, robots can make a one-way trip. No need to store fuel to bring them all back, just enough for a few dozen of them to send a sample back to a central ship in orbit, which can then pack up the samples and send them back on a relatively small rocket that weighs a few hundred pounds.

Re:We'll Never Know For Sure (1)

ArsonSmith (13997) | more than 4 years ago | (#30656346)

3.8 billion years is a long ways for humans to time travel and see. guess we'll just have to continue to make educated guesses off the data provided by the rovers and current orbital observers.

Re:We'll Never Know For Sure (0)

Anonymous Coward | more than 4 years ago | (#30656636)

If u think the sun as a dimming candle, the region around mars could holding life back then, when the sun was hotter.

Re:We'll Never Know For Sure (0)

Anonymous Coward | more than 4 years ago | (#30657118)

ESL fail

Re:We'll Never Know For Sure (1)

FreeFull (1043860) | more than 4 years ago | (#30658872)

The Sun is actually outputting more energy right now than it was back then

Images of mars (-1, Offtopic)

Ralz (1634999) | more than 4 years ago | (#30655514)

Taking images of Mars is fine, but if they start taking pictures of Uranus you should call the police.

Re:Images of mars (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#30655632)

Even toddlers are mature enough to know that your "joke" reeks of pathetic immaturity. Seriously, even an embryo with a partially-grown brain stem would find your attempt at humor to be absolute shit.

Re:Images of mars (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#30656340)

Hahaha you said "shit".

How do they determine those dates? (-1, Redundant)

aristotle-dude (626586) | more than 4 years ago | (#30655914)

I'm probably going to get modded down or flamed for being a heretic for daring to question modern scientific orthodoxy but here is goes. How are these dates determined? What the the reference point? In the classic scientific method, you have to have a known value as a reference or control. What is this reference or control used to calculate these date? Has this reference point/control been verified through the scientific method or is it based on supposition to support a hypothesis?

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".

Re:How do they determine those dates? (1)

pnewhook (788591) | more than 4 years ago | (#30656002)

What proof would satisfy you?

Re:How do they determine those dates? (0, Redundant)

ArsonSmith (13997) | more than 4 years ago | (#30656428)

--
Universal health care is a good thing. It's not socialist. Get over it.

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.

Off Topic (4, Funny)

Belial6 (794905) | more than 4 years ago | (#30656716)

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.

Re:Off Topic (1)

pleappleappleap (1182301) | more than 4 years ago | (#30657484)

The proper response is, "And you are as dumb as a box of rocks."

Re:Off Topic (2, Funny)

Belial6 (794905) | more than 4 years ago | (#30658690)

At that point I'm not sure she would have understood what that meant.

Re:How do they determine those dates? (0)

Anonymous Coward | more than 4 years ago | (#30657378)

"universal helthcare is socialist. whether or not it is a good thing remains to be seen."

Government employees seem to like it, including Senate, Congress (same ppl who say it's bad for us) and the army.

Re:How do they determine those dates? (2, Insightful)

pnewhook (788591) | more than 4 years ago | (#30657454)

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.

Re:How do they determine those dates? (1)

Jaysyn (203771) | more than 4 years ago | (#30660984)

Don't forget: Firemen - The Red Truck Menace!

Re:How do they determine those dates? (1)

oldwarrior (463580) | more than 4 years ago | (#30657458)

Actually universal h.c. is good and not totalitarian. It is Government-run healthcare that is intrinsically oppressive and untenable to freedom loving peoples.

Re:How do they determine those dates? (1)

pnewhook (788591) | more than 4 years ago | (#30657494)

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.

Re:How do they determine those dates? (2, Interesting)

Beardo the Bearded (321478) | more than 4 years ago | (#30658746)

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.)

Re:How do they determine those dates? (1)

ArsonSmith (13997) | more than 4 years ago | (#30659018)

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.

Re:How do they determine those dates? (0)

Anonymous Coward | more than 4 years ago | (#30659920)

I buy the amount of healthcare I want.

That wouldn't change under a Canadian system or under the proposed changes to the US system. If you've got the cash spend away! The changes in the US are aimed at those who can't afford healthcare.

Re:How do they determine those dates? (1)

TempeTerra (83076) | more than 4 years ago | (#30660720)

You're (sic) healthcare is up to the whims of a politician.

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.

Re:How do they determine those dates? (1)

EpsCylonB (307640) | more than 4 years ago | (#30659212)

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.

Re:How do they determine those dates? (1)

lessthan (977374) | more than 4 years ago | (#30659306)

I don't get why you said

whether or not it is a good thing remains to be seen.

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.

Re:How do they determine those dates? (2, Informative)

Sir_Lewk (967686) | more than 4 years ago | (#30656110)

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.

Re:How do they determine those dates? (1, Informative)

Anonymous Coward | more than 4 years ago | (#30656218)

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."

Re:How do they determine those dates? (0)

Anonymous Coward | more than 4 years ago | (#30656970)

The problem with these remote techniques is they are what amounts to an educated guess. They are assuming a given frequency of impacts when we know they tend to come in waves and it's impossible to know the frequency difference between the Earth, Moon and Mars. Also it's always assuming that no global event wiped out the craters. Lets say atmosphere and oceans kept Mars from developing clearly visible craters until a billion years ago and being positioned where it is Mars got more impacts so the math indicates a date that would be billions of years off. Even established dating methods like carbon dating are often wrong. Generally for accurate dating they compare multiple sources like soil compaction, it's why pristine sites are important, as well as things like pollen and layers of volcanic ash from known events. The problem with Mars is they have to guess mostly based off one questionable technique. Until direct samples can be taken and tested it'll always be guesswork.

Re:How do they determine those dates? (1)

mcatrage (1274730) | more than 4 years ago | (#30656172)

Um questioning science honestly is something people like. Denying science or questioning science via misinformation would make you a heretic.

Re:How do they determine those dates? (1)

Belial6 (794905) | more than 4 years ago | (#30656916)

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.

Re:How do they determine those dates? (4, Informative)

locallyunscene (1000523) | more than 4 years ago | (#30656250)

FTFA:

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 [wikipedia.org] ]

Re:How do they determine those dates? (1)

vlm (69642) | more than 4 years ago | (#30657814)

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 [psi.edu]

Re:How do they determine those dates? (4, Insightful)

Chris Burke (6130) | more than 4 years ago | (#30656292)

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.

Re:How do they determine those dates? (-1, Redundant)

Anonymous Coward | more than 4 years ago | (#30656308)

From TFA:

"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."

Re:How do they determine those dates? (1)

Bruce Dawson (1079221) | more than 4 years ago | (#30656418)

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.

Re:How do they determine those dates? (1)

edrobinson (976396) | more than 4 years ago | (#30656498)

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?

Re:How do they determine those dates? (1)

Sir_Lewk (967686) | more than 4 years ago | (#30656588)

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)

Re:How do they determine those dates? (0)

Anonymous Coward | more than 4 years ago | (#30656656)

"Contrary to what the "internet" likes to tell you, many people question what scientists say..."

It's just that many people are to lazy to go look for answers to those questions, and in many cases understanding the answers requires an education in science, or at least requires a lot of time spend reading background material (meaning the answers don't fit in the forum).

Now if only many people would be so skeptical about politics as they are about science.

Re:How do they determine those dates? (4, Informative)

Ephemeriis (315124) | more than 4 years ago | (#30656930)

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.

Re:How do they determine those dates? (3, Insightful)

Daniel Dvorkin (106857) | more than 4 years ago | (#30657646)

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.

Re:How do they determine those dates? (0)

Anonymous Coward | more than 4 years ago | (#30659552)

Simple misunderstanding of the scientific method. It is designed to make educated guesses and see if the data collected by a properly designed experiment bears them out. Science then describes the relationship of the data to the educated guess (us scientists call this guess a "hypothesis", by the way) in what's called "Experimental Results" or a "Conclusion". Proof is outside of the domain of Science. The word "proof" should only be used in relation to mathematics or formal logic.

That having been said, I too am interested in how they determined the age of the lakes. It sounds like they used spacial density of meteorite impacts within the bodies of the lakes, compared that to the surrounding surface, and extrapolated from there. Not sure if that's correct, though, or the validity of the method they used.

Re:How do they determine those dates? (1)

hesaigo999ca (786966) | more than 4 years ago | (#30660644)

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!

Confusing headline (0)

Anonymous Coward | more than 4 years ago | (#30655918)

At first I thought it was another one of those "AMAZING NEWS! MARS HAD WATER!" which I've been reading for years now.

At the risk of being serious... (2, Insightful)

tetrahedrassface (675645) | more than 4 years ago | (#30655934)

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.

Re:At the risk of being serious... (1, Redundant)

neo-mkrey (948389) | more than 4 years ago | (#30655990)

All these worlds are yours, except Europa, attempt no landing there...

2010 (0)

Anonymous Coward | more than 4 years ago | (#30660286)

First It has to ignite Jupiter...

Re:At the risk of being serious... (1)

elrous0 (869638) | more than 4 years ago | (#30656434)

Even if Europa does contain such life (and that is still a VERY big "if"), the effort to pinpoint it and drill down to it would be a helluva lot more trouble than sending any little probe to Mars. That's *way* beyond NASA's budget or ambitions. Admittedly, it would be no more or less pointless than any of their other money-sinks, but don't hold your breath.

Re:At the risk of being serious... (1)

sznupi (719324) | more than 4 years ago | (#30656472)

And we can't explore both...why exactly? (plus mission to Europa is being worked on; though it will be not an easy feat)

As a matter of fact, why do you want to limit us to Europa? Why do you dismiss Mars outright? (there are still those weird methane emissions we have to sort out; and possibility of subsurface water) Also, what makes you think Europa is more likely to harbor life than Ganymede, Callisto, high atmosphere of Venus or even Enceladus?

Mars has one big advantage of being relatively easy to get there too.

Re:At the risk of being serious... (1)

tetrahedrassface (675645) | more than 4 years ago | (#30657028)

I didn't say anything about limiting us to Europa, you did. It would be a very good thing to explore not only Europa but the other moons you list. The reason we keep going back to Mars isn't so much for the science because there is a hell of a lot of other and possibly more interesting science that could be better served by going to Europa, or maybe Enceladus. The reason I dismiss Mars outright, on its face, and with no reservations is that given our budget it would be better to let Mars rest for a time, while other missions could be given larger budgets and higher priority.

In short Mars has received a disproportionate number of missions yet we keep sending rovers and landers to Mars! Have we found life on Mars yet? Have we found liquid water? Have the rovers found water ice? Sure the Mars Polar Lander found some ice, but the rovers aren't up there are they? Other than the pretty pictures what have we learned other than there are a lot of blueberries on Mars, and some dust-devils? What pray tell?

We could learn a lot from Europa because Europa has a small iron core which is heated by tidal friction, and under the the 3km of ice there may in fact be 100-200 kilometers of salt water . Now it is odd, that our space agencies, that claim to be searching for life willfully have ignored Europa other than a few flybys. Of all the planets and moons of this solar system, Europa stands the best chance at harboring life, and a Europa orbiter that incorporated radar and more could have been built and launched 10 years ago. In fact Europa may have more water than all of Earth's oceans combined!

We keep going back to Mars because it is relatively easy, yet as per John F. Kennedy, we should do the hard things, but we don't do we because Mars is just too easy, and the thumb sucking populace loves the pretty pictures. I say focus somewhere else for the next 10 years. Mars has had its time. We can always go back to Mars when we want right? Because as you say, it is so easy..

Re:At the risk of being serious... (2, Informative)

Grishnakh (216268) | more than 4 years ago | (#30657810)

We could learn a lot from Europa because Europa has a small iron core which is heated by tidal friction, and under the the 3km of ice there may in fact be 100-200 kilometers of salt water . Now it is odd, that our space agencies, that claim to be searching for life willfully have ignored Europa other than a few flybys.

Maybe they're put off by that 3km of ice. How exactly are they going to drill through that ice, when the best we've managed so far with remote probes is to launch a few wheeled rovers to a dry planet very nearby, and even those have problems with broken wheels and getting stuck in sand. We're nowhere near the point where we can launch a probe that drills through 3km of ice and maneuvers around in whatever's below, and then manages to maintain communication through that 3km of ice.

Don't forget, our budget for space exploration is peanuts. Canceling the Mars missions isn't going to add enough to the budget to accomplish these missions you dream of, and we can't enlarge NASA's budget because we're too busy fighting oil wars and bailing out mismanaged private companies.

Yes, JFK said we should do the hard things. He didn't say we should do the impossible things. You have to walk before you can run.

Re:At the risk of being serious... (1)

vlm (69642) | more than 4 years ago | (#30657904)

Mars is just too easy

Your rant was actually doing pretty good until there. Check the mars mission failure rate... If Europa were say, a hundred times more difficult, then the odds of total mysterious failure in Europa currently approach 100%. But if we can improve our reliability by trying stuff in easier mars missions, maybe someday a Europa mission wouldn't be a guaranteed failure, and might even work, maybe.

Re:At the risk of being serious... (1)

Chris Burke (6130) | more than 4 years ago | (#30660124)

I didn't say anything about limiting us to Europa, you did.

Uh, you said "forget Mars", so it seems pretty clear that whatever unlimited space program you're imagining, it is limited to not-Mars.

In short Mars has received a disproportionate number of missions yet we keep sending rovers and landers to Mars!

Because we still have a ton of things to learn and it's low-hanging fruit. Relatively cheap missions with a relatively high measure of success and an enormous payoff in science. We will be sending rovers to Mars for a long time and still learning stuff. So why stop? Cus you're bored with science on Mars?

Have we found life on Mars yet? Have we found liquid water? Have the rovers found water ice? Sure the Mars Polar Lander found some ice, but the rovers aren't up there are they? Other than the pretty pictures what have we learned other than there are a lot of blueberries on Mars, and some dust-devils? What pray tell?

So because we haven't answered those questions, and because he current rovers aren't at the poles, we should stop sending rovers? Sounds like a good reason to keep going! And we've learned a shit-ton on Mars. But there's a ton more still to learn, too.

We could learn a lot from Europa because Europa has a small iron core which is heated by tidal friction, and under the the 3km of ice there may in fact be 100-200 kilometers of salt water . Now it is odd, that our space agencies, that claim to be searching for life willfully have ignored Europa other than a few flybys.

Um... I think you need to think a little bit more about the challenges just in the Mars lander project, then think a little bit more about that 3km of ice and 100km of salt water, on a heavenly body that on its surface receives 1/11th as much sunlight as Mars. "Willfully ignore"? Try "are fascinated by, but realize it's not feasible to dig under yet". The flybys are your clue that they are not ignoring Europa. There's interest in landing something on it, but that is a mission that is going to be in the pre-planning stages for a long time.

We keep going back to Mars because it is relatively easy, yet as per John F. Kennedy, we should do the hard things, but we don't do we because Mars is just too easy, and the thumb sucking populace loves the pretty pictures. I say focus somewhere else for the next 10 years. Mars has had its time. We can always go back to Mars when we want right? Because as you say, it is so easy..

Mars is plenty hard enough. "Relatively" easier than exploring the oceans of Europa is hardly easy. Why go back to Mars later when "we" -- meaning not you -- want to go there now? Because you're bored? So what, scientists aren't. I say bring on the MSL and a dozen other follow-on probes. And explore other bodies, too.

Re:At the risk of being serious... (1)

Chris Burke (6130) | more than 4 years ago | (#30656866)

No, we can't forget about mars, because we still have a crap-ton of stuff left to learn about it. So much so that just about everything we do there results in us learning something new. Hell, just a day or two ago, I learned that the Spirit rover trying to work its way free from some sand had revealed sulfate deposits. And that was quite literally just scratching the surface.

As others have pointed out, Europa missions are in the works, but are quite a bit harder to do than Mars, especially if you think the interesting stuff lies underneath the ice. Just think about the effort that went into the Mars rovers, then imagine working out how to design a lander that can drill through the ice, maneuver underneath it, and then somehow communicate with an orbiter through the ice. And then once you've designed and built it, it will still take a long time to actually reach Jupiter.

In the meantime we've got the Mars Science Laboratory planned for launch in 2011, and if it's half as successful at its mission as Spirit and Opportunity were at theirs, we're going to learn a ridiculous amount about the red planet.

Re:At the risk of being serious... (1)

tetrahedrassface (675645) | more than 4 years ago | (#30657162)

*nod*

We need to learn a ridiculous amount about a few other places too. But, yeah.. :)

Terraforming? (0)

Anonymous Coward | more than 4 years ago | (#30656148)

So.. Mars is the best candidate for terraforming tests?

Re:Terraforming? (2, Informative)

phrostie (121428) | more than 4 years ago | (#30657250)

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.

Re:Terraforming? (1)

Daniel Dvorkin (106857) | more than 4 years ago | (#30657952)

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?

Re:Terraforming? (1)

WalksOnDirt (704461) | more than 4 years ago | (#30658582)

Am I missing something?

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.

Re:Terraforming? (1)

Daniel Dvorkin (106857) | more than 4 years ago | (#30658686)

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.

Re:Terraforming? (1)

WalksOnDirt (704461) | more than 4 years ago | (#30659794)

Mars once had a much thicker atmosphere, so it must have gone somewhere. A mechanism for its loss to space has been proposed [nasa.gov] , 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).

Re:Terraforming? (1, Interesting)

Anonymous Coward | more than 4 years ago | (#30658782)

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.

Global Warming? (1)

0100010001010011 (652467) | more than 4 years ago | (#30656158)

So would 'global warming' have prevented this type of disaster?

Re:Global Warming? (0)

Anonymous Coward | more than 4 years ago | (#30656702)

Of course it would.

    Here is what the Pro Global Warming idiots seem to forget

Earth Warm and Wet = Life

Earth Cold and Dry = Absence or Retreat of life

This of course applies to other planetary bodies

    So they will reply but Antartica blah blah

But they forget, Antartica is a part of the large and warmer ecosystem of Earth in totality and if Antartica was the norm, its doubtful life would have taken hold.

Re:Global Warming? (1)

Abcd1234 (188840) | more than 4 years ago | (#30657480)

So would 'global warming' have prevented this type of disaster?

Uh, no. Or do you really believe global warming would've magically allowed Mars to hold on to its atmosphere?

Re:Global Warming? (1)

frith01 (1118539) | more than 4 years ago | (#30657620)

No. The problem with mars is that it lacks the gravity to keep gaseous particles bound to it's atmosphere, such that the solar wind removes a really small % of it's atmosphere annually.

Re:Global Warming? (2, Insightful)

0100010001010011 (652467) | more than 4 years ago | (#30657732)

So if you were generating the same % of gas annually, would it not be in equilibrium?

Re:Global Warming? (1)

frith01 (1118539) | more than 4 years ago | (#30658442)

Correct, which is why we can still breathe :) Realize that most of a planet's mass is not involved in the generation of the atmosphere, and that aside from Volcanos not much change occurs on a 1000 year scale unless biological processes are involved. Volcanic activity has also substantially reduced on Mars, which would have been the other major factor in producing atmospheric gases from minerals / rocks.

The off-set of having a warmer atmosphere though is that warm things expand, which makes them easier to knock out of the atmosphere.

Even the Earth though loses the lightest elements to space, such as Hydrogen, and Helium. The only net addition of those elements are through
comets / asteroids that occasionally visit.

Re:Global Warming? (1)

al3 (1285708) | more than 4 years ago | (#30659044)

Does the earth's magnetic field not also provide our atmosphere a degree of protection from solar wind that Mars does not benefit from?

Re:Global Warming? (1)

frith01 (1118539) | more than 4 years ago | (#30660244)

From Charged particles, yes. Not all space particles are charged, or are slowed down by magnetic fields.

Mars is lacking a magnetic field, which is also believed to be why volcanism has stopped. (molten core not large enough, or maybe fully solid )

Yeah, that's great Mars (1)

elrous0 (869638) | more than 4 years ago | (#30656468)

But what have you done for us LATELY?

the planet lost most of its atmosphere ... (1)

oldwarrior (463580) | more than 4 years ago | (#30657212)

KHAN!

Re:the planet lost most of its atmosphere ... (2, Funny)

SnarfQuest (469614) | more than 4 years ago | (#30657800)

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.

ama8e (-1)

Anonymous Coward | more than 4 years ago | (#30657240)

liquid exchange between craters? (1)

kj_kabaje (1241696) | more than 4 years ago | (#30657674)

the photo shows liquid exchange between craters. Couldn't this be something apart from water?

Are we next (2, Funny)

SnarfQuest (469614) | more than 4 years ago | (#30657706)

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.

This nerd's theory (1)

theGhostPony (1631407) | more than 4 years ago | (#30657766)

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.

Re:This nerd's theory (0)

Anonymous Coward | more than 4 years ago | (#30657920)

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).

Speak for yourself. My ancestors were the original inhabitants of Krypton who seeded life here after determining their home world was doomed to destruction (a nuclear chain reaction deep within the planet's unstable Uranium core is my guess).

Noah says... (0)

Anonymous Coward | more than 4 years ago | (#30658842)

Everyone knows that all the water came from Mars to Earth - that's why it rained for 40 days and 40 nights.

I love the way scientists talk... (1)

osu-neko (2604) | more than 4 years ago | (#30659700)

"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.

I can see your boobs... (1)

prometx42 (1107413) | more than 4 years ago | (#30660880)

...aaaaaaand...now we're safe from terror...

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