Firstly how would we do this there are a few problems with mars today, the temperature which is an average of -55 Celsius, the pressure of the atmosphere which today would boil water at room temperature and is mostly CO2 which is not breathable by humans, and the magnetic field without it the solar wind would slowly rip away its atmosphere. But if we did terraform mars it would be awesome!
So how would we raise the temperature? One way would be to introduce a lot of greenhouse gases like carbon dioxide into the atmosphere if you raised it enough it would melt the ice caps which would release more CO2 since the ice is full. But how would we do that we couldn't easily ship the CO2 from our planet (though it would be a good way to get rid of global warming) it wouldn't be very easy to ship, but if we didn't plan to colonize mars we could nuke its ice caps(which might be a good way to get rid of some nukes) but it would leave it radio active for a while, or we crash asteroids into it since asteroids have some amount of ammonia (which is a powerful green house gas) and it would warm up the ice caps.
Okay, supposing we managed one of those methods we would now need an atmosphere of oxygen to do this we would have to probably introduce some sort of bacteria, that would be able to cope with the soil and emit oxygen depending on whether how efficient this was we might have to make large glass domes in which we could produce oxygen by farming and let some of it out into the atmosphere...
Now what about the magnetic field, if we produced the an atmosphere we would want to keep it so we would probably need a artificial magnetic field, we could do this by having strong magnets positioned in L1 orbit they would have to be pretty strong with a magnetic dipole of 1 to 2 tesla, with a magnetic field mars would slowly gain atmosphere.
So what if we did it? It would be totally awesome, and a new race would be born (flat marsers). The human race would be secured if a super volcano blew on earth it would be catastrophic but at least humans would still be alive! perhaps some endangered wild life could be brought and saved on the new earth!
Thanks for reading!!!
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2018 from 2018 to 2018