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NASA's Maven Mission Solves the Mystery of Mars' Lost Atmosphere
StartsWithABang writes: If you came to the Solar System some 500 million years after its formation, you would've found two world with oceans of liquid water, continents and all the conditions we know of for life to begin thriving: Earth and Mars. But unlike our own world, Mars' organic history was cut short when it lost its atmosphere and became a barren, desert wasteland. While we had some pretty compelling theories as to how this happened, it was only with the advent of the Maven mission and its first science results that we discovered exactly how, how fast and when Mars lost its atmosphere. One cool discovery: aurorae appear diffuse and all over the entire night sky on Mars!
The summary is missing important information. As TFA discusses, the primary issue was (as already strongly suspected) the loss of the magnetic field around Mars. With only a very weak magnetic field nothing protected the planet's atmosphere from the solar wind which blasted the atmosphere away over a time span probably in the hundreds of millions of years. This last result, the slow loss of the atmosphere is a genuinely novel and important discovery because as TFA discusses this makes it more plausible that if there was life on Mars that it would have had time to evolve to survive the gradually harsher environment. The research also suggests that Mars will become completely airless in around 2 billion years.
Scientists discover this one weird trick to remove a planet's atmosphere!
#DeleteChrome
Why did Mars lose its magnetic field? Anything to do with its core solidifying?
You and me both know it was aliens what did that to Mars.
http://www.dailymail.co.uk/sci...
You are welcome on my lawn.
The article says it would last for a while if we could, so...back of the envelope with probably horribly wrong numbers. Martian atmospheric density at the surface is 0.020 kg/m^3, human survival limit is something like 0.6 kg/m^3, so we need to add 29x current martian atmosphere to be long-term human survivable without a mask (for children and older, babies would still need higher pressure). NASA puts current atmospheric mass at 2.5e16kg, so we need to add 7.25e17kg. If we wanted to accomplish that task over a thousand years, or roughly 3.15e10 seconds, we would need to produce about 2.30e7kg of atmosphere every second for the duration. (At that speed, the loss rate of Mars's atmosphere due to solar wind is absolutely negligible.)
Martian surface area is 1.44e14m^2, which means we'd need to pull ~5,000 kg of atmosphere out of every single square meter of the planet if we don't have some other source. I don't know what density or composition Martian rock is, but rock in general is about 2.5g/cm^3, or 2500kg/m^3. So you might need to dig several meters into the ground to get what you're after, and expend one hell of a lot of energy to crack the oxygen out of it, but it's not like you'd need to dig a whole mile down across the whole planet or anything.
...new idea. If you already have the crazy tech necessary to do all that, just have your robots fabricate enclosed colony space instead. Mine, smelt, build roof. Yeah it's still ridiculous future technology, but if all you want is to make the place livable, it's a lot faster if you just make a bunch of buildings. Hell, in the amount of time it would take to crack all those atmospheric gases, you could have your crazy future robots just build an entire planet-covering roof for an enormous habitation space. It would take less work.
Or we relocate Callisto, as in arrange a collision between Mars and Callisto. If that isn't enough energy to remelt Mar's core, then add Mercury. Or probably bang Mercury and Mars together first, then drop in Callisto so you don't lose the water that makes up Callisto. That might get you a habitable planet once the crust hardens up again.
In short, we would need to capture a small fraction of the mass of one of the gas giants, and transport it to Mars. It would be interesting to see a proposal on how that could be done.
Heat mars....perhaps covering it in dark dust at the polar caps, put some machines there to pump out CFCs...global warming will cause sublimation of dry ice into carbon dioxide, a green house gas...planet heats more, more is sublimated, etc...hopefully get a positive feedback cycle going...
Maybe comet/asteroid impacts if needed....
Reflectors positioned to focus sunlight...
Nuclear detonations....
Submission claims that for the first 1/2 billion years there were 2 planets with water and air. What about Venus?
Venus was also possibly inhabitable for the first part of its life, perhaps billions of years, until the Sun got warm enough to boil the Venusian oceans and created a runaway greenhouse affect.
Same thing is predicted for the Earth as the Sun continues to heat up (due to having a higher percentage of helium with time and therefore higher density) perhaps in as soon as 500 million years.
https://en.wikipedia.org/wiki/Inverted_totalitarianism
18+ year old theory: http://www-ssc.igpp.ucla.edu/p... I though I was losing my mind. The article, OK the summary, seems to imply no one ever thought of this.
I believe the normal science fiction solution is throwing comets at it. The comets can add water and various gases (although ammonia and methane probably aren't what you want for a liveable atmosphere) along with various organics.
I'm not sure it would do us a lot of good, but it might give Mars a chance to develop life of its own, especially if seeded with simple life from Earth.
Honestly, If we're going that far, I'd say a better target is Venus. Venus has no water. One of the theories for why Venus lacks a magnetic field is that its crust is too inflexible to support plate tectonics without water, which means the core doesn't cool fast enough to allow convection. Adding water might be all it takes to restart the magnetic field on Venus. The technology for all this is so far out there we may as well assume we have a way to get rid of a large chunk of Venus' atmosphere (maybe move it to Mars?), reducing the pressure down to levels where people could survive on the surface.
I don't think any of this will actually happen, mind you. It's fun to think about, though.
Those who can't do, teach. Those who can't teach either, do tech support.
So what is the calculation of when the Earth's core will freeze over or is there enough radioactivity to last until the Sun finally expands and consumes Earth?
Perhaps, but it is more likely that we will have our hands full just surviving global warming here on Earth caused by the collective will of humanity.
We just need Schwarzenegger to go to Mars and find some alien artifacts to make the atmosphere breathable in about 30 seconds.
Venus should be a candidate for colonisation, it would probably be much cheaper and easier:
Should We Colonize Venus Instead of Mars?
Venus: too much atmosphere, too hot.
Mars: not enough atmosphere, too cold.
The answer is so simple even a hipster twat who paints himself blue and has a shaved head and a silly beard could work it out.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Elon Musk suggested nuking Mars to warm it up.
How about engineering controlled tiny asteroid collisions at the poles, replace the solar wind matter being stripped off.
Trouble is getting there in the first place won't be.
It is far more difficult (and costs a LOT more energy) to send a rocket to the inner planets than to an outer planet. The reasons are a bit complicated for a slashdot post (it's about how much orbital velocity you need around the sun in a smaller orbit and then to get into planetary orbit you have to slow down by a lot more).
It's possible and we've sent probes to venus but they used a lot more fuel than the same size probe would need to Mars despite Mars being further away (actual distance is not the biggest concern with orbital mechanics). For something with enough mass to contain humans - that difference goes up at a near exponential rate.
Now there is probably a point where the difference in terraforming costs will outweigh the difference in travel cost. If you're going whole-hog "build a colony" it may well be true - but we're a while away from that yet, and for early stage experiments Mars is almost certainly the cheaper option.
Unicode killed the ASCII-art *
...Which the Democrat kids can then mug them for. So the same income redistribution takes place with either party.
"...it's a lot faster if you just make a bunch of buildings. "
Which could be partly earth-sheltered to reduce radiation.
"Let's hope there is a fifth dimensional being because none of this will happen with current leadership."
Of course. It would take little people who are good at math, fearless about engineering and have a track record of long-term thinking. Oh, wait -
(They mention this in the video but it still seems important to state) Venus is much more inhabitable than Mars is. The biggest issue at the moment is the fact that Venus's surface temperature is above 450 C. We currently know how to make a planet warmer over time, but we don't know how to make a planet that much cooler for multiple reasons. Partially because of the fact that with a sulfuric atmosphere and that temperature it becomes very difficult to even get any machines there for colonization.
Also no visible light reaches the surface due to its thick atmosphere. And one final note about Venus, its rotation is so slow it takes 243 days for it to complete one rotation. Therefore a year on Venus is shorter than a day on Venus.
In other words it would take a lot better technology to colonize Venus that it would take to colonize Mars. We could begin on Mars mostly with current technology, a few things would probably need to be improved first, but that could be done in the next decade or so.
But in order to build a colony on Venus we would need to invent the technology to keep the colony off of the surface. And this technology is not easy to test here on earth, because we would need to duplicate Venus conditions and NASA likes to test the crap out of its technology before sending it. While I understand that it is a shorter trip, and it has better gravity. I don't think it would be easier or cheaper at this time.
In the long run a colony should definitely be looked at on Venus, partially because it could teach humans how to terraform planets which would definitely be helpful in the long run. But when we talk about colonizing other planets Mars makes the most since at this time with current technology.
There is no behind your back, punk, you could create an account and see the signature just like everyone else. But, since you seem to be incapible of doing that, here is the signature:
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APK is a Troll, please ignore him. If he had anything to say, he'd have an account.
Also, why would I care if your crap hits Google? Do you think it matters how much insane shit posting show up? You are the one that is looking bad, not me, so it doesn't bother me one iota.
APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
But getting to low orbit for landing Mars needs 2.1 km/s while venus needs 3.3 km/s.
You looked at the transfer alone but a trip is more than one burn. You have to add them all up.
One thing I havent factored in is the increased possibility of aerobreaking around venus. Not sure how that changes the final scores.
Unicode killed the ASCII-art *
Anti-Mars people seem to miss that point. If you are on Mars surface, Mars is shielding you from half the constant radiation. Create buildings with a thick roof on top and big windows on the side, like most apartment and office buildings, and you are about as protected as on Earth.
Venus is actually a fairly interesting prospect for colonization. You obviously don't go down to the surface with its lead-melting temperatures. However, about 50km from the surface you have temperatures a bit above freezing, the atmospheric pressure of roughly one atmosphere, and gravity that's very near Earth's. It's about the most earth-like place in the solar system that's not on Earth itself. The atmosphere is mostly CO2, which is a dense gas, so a balloon filled with breathable air would float. You have plenty of solar radiation during the day, the air contains nitrogen and trace amounts of water, and the magnetic field and dense atmosphere gives you some protection from the sun's radiation. On the downside though, the wind speed is hundreds of miles per hour, the days are really long, and if your balloon sinks you're pretty much a goner.
Find a planet between them that has just the right amount of atmosphere and it neither too hot or cold?
But what's the point about the cost of sending people there? Apart from the first few colonists - a few thousand - they'll breed their own inhabitants. why would they want poor foreign immigrants from a polluted or nearly uninhabitable planet like Earth will be in the thousands of years that the project would take.
Or ... were people thinking of dreams about the future being a substitute for dealing with current problems?
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"