5 ms·

I thought part of the problem was the lack of a magnetic field? I'm not sure if that has anything to do with keeping an atmosphere or just the ability to surviv

• ryanmercer 8y ago
  The magnetic field keeps the solar winds from stripping away atmosphere, that happens in appreciable amounts on a geological time scale. It does offer some radiation protection too but it would take centuries with current technological means to raise the temperature enough on Mars to start a runaway greenhouse effect... as it stands now you'd basically have to go set up power plants on Mars then start producing greenhouse gasses from local materials, releasing them into the atmosphere, until you got that estimated 5C average temperature increase which would then start melting the polar caps' dry ice and water ice (as well as what is in the regolith all over the planet) and go runaway. At that point you'd be outpacing what the solar winds are peeling off the atmosphere (IIRC it's something like 100 grams a second which sounds like a lot but not on a planetary scale).