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What Happened To the Martian Ocean and Magnetic Field? (theatlantic.com)
schwit1 writes with this story at The Atlantic that explores what may have destroyed the Martian atmosphere and ocean. The question of whether there is life on Mars is woven into a much larger thatch of mysteries. Among them: What happened to the ancient ocean that once covered a quarter of the planet's surface? And, relatedly, what made Mars's magnetosphere fade away? Why did a planet that may have looked something like Earth turn into a dry red husk? “We see magnetized rocks on the Mars surface,” said Bruce Banerdt, the principal investigator of the InSight mission to Mars, which is set to launch in March. “And so we know Mars had a magnetic field at one time, but it doesn't today. We would like to know the history—when that magnetic field started, when it may have shut down.”
... that because of Mars' small size, it cooled faster, thus freezing its outer core and shutting down its dynamo? Isn't Venus the far greater mystery? Nearly the same size as Earth, yet no magnetic field and what appears to be occasional whole-crust overturn rather than plate tectonics? Isn't that the one we need to solve?
The human body can be drained of blood in 8.6 seconds given adequate vacuuming systems.
Mars has no Magnetic field because it's core cooled and is no longer a active moving iron mass. it cooled faster as it has very little radioactive isotopes and being further away from the sun it has less energy pounding it to slow the cooling.
http://www.scientificamerican....
Plus we had an event late after the formation of the planets in the solar system that also added a buttload of energy, when the moon was formed from a planetary sized impact.
Do not look at laser with remaining good eye.
While trying to figure out what scripts to allow to make moderation work I accidentally ended up modding this as flamebait. For reference, I was going for informative. I believe posting a reply will undo that. So thanks for the post, Lumpy. I owe you +1.
It was Marvin the Martin, in the Valles Marineris, with an Illudium Pu-36 explosive space modulator.
systemd is Roko's Basilisk.
We all turn into solar radiation zombies.
You have about 1.2 Billion years to prepare for this, so start digging and stocking your bunker now.
Do not look at laser with remaining good eye.
Don't we just have to get Quaid to Mars to fire up the alien machine?
"I don't which is worse, that everyone has a price, or that the price is always so low"--Hobbes
20+ posts already, and no one mentioned Global Warming yet? How could you, guys, miss this opportunity to refresh the fear in the hearts of your followers? If you keep burning fossil fuels, our planet too will become an airless desert devoid of life. Whether it will heat up or cool down is an impolite question, but something will happen, unless you install solar panels on your roof.
The "point of now return" — like the second coming of a deity of some unscientific cult followed by the unwashed — has been within "only a few years" for the past 4 decades.
Gebyy zl gnvy.
In Soviet Washington the swamp drains you.
It is thought to be related to the disappearance of the Martian atmosphere. The magnetic poles divert the solar wind towards themselves, and prevents it from hitting most of the planet. When the magnetism disappears, the solar wind blows the atmosphere away.
When the atmosphere disappears, the pressure is reduced, and with it the boiling point of water, until water can only have two states - ice and gas form. The water that doesn't turn into ice goes the same way as the rest of the atmosphere.
Aren't we due to stick our heads out from the protective Galactic Disk and magnetosphere to get fried by intergalactic cosmic rays long before then?
Apocalypse Cancelled, Sorry, No Ticket Refunds
It's this exactly. Without a magnetic field, the solar wind dried out the planet and blew away a large amount of the already thin atmosphere. The low gravity didn't help any. The planet had a lot going against it from the beginning and was probably never a good place for complex life to appear. Barring some sort of cosmic change like how we got our moon and added a huge amount of iron and mass, Mars was always doomed to end up freeze-dried.
We currently have no way of fixing this problem so all the grand plans to terraform Mars won't work, unless they also restart the magnetic field, which we don't know how to do. It might take slamming a proto-planet into Mars to get things going again, which we can't currently do, and which would also make the planet essentially unusable for hundreds of millions of years, at least.
It also risks all kinds of other issues like disturbing other planets and introducing a lot of chaos into the solar system. But luckily we don't know how to knock planets into each other. And I suppose if we DID and we had that sort of tech, we would not need to bother with Mars. We'd just find a suitable planet elsewhere, which is probably easier.
Sig for hire.
The way I understand it the lost of the magnetosphere allows the solar wind to push the ozone back to the nightside and some off into space, this thins ozone lets the UV disassociate more water vapor (that's lighter than air) into hydrogen and oxygen, the hydrogen is lost to space because it's so light and the oxygen that doesn't get blown off into space oxidises any methane or carbon monoxide in the atmosphere on the way back down to the surface. This causes the atmospheric pressure to decrease, which cause the water to boil at a lower temperature, putting more water vapor into the air to be dissociated and lost, in an accelerating death spiral.
Apocalypse Cancelled, Sorry, No Ticket Refunds
Is the backwards spin evidence that cats had used the Venerian spin to get their planet moving.
"... it would still be there for tens of thousands of generations." Not good enough. If you make Mars habitable, that work will get leveraged, as in it will be inhabited. What will those distant generations think if we set up an unstable atmospheric dynamic and knowingly doom future generations to suffocating? The atmospheric dynamic must be stable, like it is on Earth. Robust and even largely self-correcting.
Not really. If we can do it once, we can keep it supplied with atmosphere in plenty of time. We keep importing resources to places that don't have them all the time. However, although about a fifth of the needed material might be already on Mars in the form of ice, the only real option would be to bring in comet type material from the oort cloud. Last time I did rough estimates on doing that, the energy needed to move all that material in ten years was measured in days total output of the sun. Move the cometary material slower, and it takes longer but the energy needed is less. Increase the time to 10,000 years, the time that an astrophysicist friend of mine said it would take for Mars, give an Earth-like atmosphere to degenerate to one that wasn't, and that makes the constant power requirement to keep Mars supplied with atmosphere at 3.8*10^14 W. That's about 2000 times what the we generate currently on the Earth, just to keep Mars' atmosphere stable.
It's also been proposed to ship Venus' atmophere to Mars, but I haven't seen any estimates on the energy needed to do that.
Even as far back as the original Cosmos series, scientists were saying that the lack of a liquid iron core to generate the magnetic field was the cause of the atmosphere leaking off into space. Okay, sounds plausible but it has me wondering why it has to be liquid when lodestone has a magnetic field and it's solid. And why isn't gravity enough to hold the atmosphere in? Or is the gravitational field too weak?
Iron looses magnetic properties at 770C which is hot but still solid. A liquid iron core has a magnetic field due to convection. Once it cools and solidify, the convection stops but the core is too hot to have a magnetic field of its own.