[Oberon]

If you want to terraform Mars, the first thing you have to do is crank up the gravity to a level that will sustain an atmosphere dense enough to breathe.

Once you've solved that problem, the rest of it should be a piece of cake. =]

[doc30]

If you want to terraform Mars, the first thing you have to do is crank up the gravity to a level that will sustain an atmosphere dense enough to breathe.

I am amazed at how many people think we just need to warm the planet and add atmosphere to get a decent pressure and temperature at the surface. What they fail to understand is that a higher gravity is needed. With the current gravity, warming the planet will result in a loss of atmosphere. With a higher temperature, the Boltzmann distribution of gas molecule speeds will have the high speed tail stretching well past escape velocity with the current gravity on Mars. Warmer Mars = less atmosphere. Or you could jusr dig really, really deep holes so the atmosphere would be of satisfactory pressure. Colonists on Mars would live in deep 'hobbit holes'. The hole depth would increase protection from cosmic radiation, too.