A few basic questions here; 1. What strength of magnetic field would be needed to LARGELY eliminate atmospheric erosion by solar winda and coronal mass ejections? 2. Assuming that it would be significantly less than that that is required for Earth, (radiation reduction rules would likely be in effect. Radiation levels are reduced by the square of the distance from the source of radiation) how much power would be required to produce such a field effect? 3. Utilizing high temperature superconducting ribbons, wrapped around the planet to produce such a field, could fields of solar panels produce enough power to produce such a field? (Don't balk at this; producing such lengths of superconducting ribbon is possible, although likely at a lower rate than we do for conventional wire, but it is possible). 4. Are the materials needed to produce such lengths of superconducting wire available on Mars, or would extraction from asteroids be needed? Obviously the above questions are fanciful speculation, but I suspect that such a system would be less expensive, more practical and less prone to failure than an L1 based magnetic shield. Not that I am faulting the initial reasoning, but an enveloping Magnetic Field would likely be FAR more effective that one protecting a planet from only one side. Besides, you'd still have some spillage from around the edges of such a shield that would still affect the planet, unless you made the shield many times the diameter of Mars itself.
wait... it is my understanding that if you somehow returned Mars' atmosphere such that it had the Earth's distribution of gases and density and then did nothing to retain it in place it would still take a period of time longer than human kind has existed for it to erode/devolve again to it's present state. That's a heck of a long time. Plenty of time for civilizations to rise and fall and even for species to rise and fall. So i don't get it...Why exactly do we need an artificial magnetic field except for the sake of OCD completionists?
bear with me here as i have dropped a few digits of memory precision on this; but I have read that the time for erosion from Earth-like levels of atmosphere for Mars from all sources of erosion and other factors like chemical sequestration and things like that is either 300 million years or else 300 thousand years from the time Mars' dynamism ended. Either way it's more time than humanity or human civilization or recorded history has existed.
Quote from: Stormbringer on 03/28/2017 12:07 pmbear with me here as i have dropped a few digits of memory precision on this; but I have read that the time for erosion from Earth-like levels of atmosphere for Mars from all sources of erosion and other factors like chemical sequestration and things like that is either 300 million years or else 300 thousand years from the time Mars' dynamism ended. Either way it's more time than humanity or human civilization or recorded history has existed.Once you have an Earth-like atmosphere it will take a long time for it to erode, but first you have to create that atmosphere. Reducing erosion will make it easier to build up the atmosphere.
bear with me here
"Despite stronger solar wind and EUV-radiation levels under the early Sun, ion escape can not explain more than 0.006 bar of atmospheric pressure lost over the course of 3.9 billion years," says Robin Ramstad. "Even our upper estimate, 0.01 bar, is an insignificant amount in comparison to the atmosphere required to maintain a sufficiently strong greenhouse effect, about 1 bar or more according to climate models."The results presented in the thesis show that a stronger solar wind mainly accelerates particles already escaping the planet's gravity, but does not increase the ion escape rate. Contrary to previous assumptions, the induced magnetosphere is also shown to protect the bulk of the Martian ionosphere from solar wind energy transfer.Read more at: https://phys.org/news/2017-12-mars-atmosphere-solar.html#jCp