Life has survived this long in space with just air and a magnetic field as protection. What we have found is that we need good shielding and to simulate gravity

Life has survived this long in space with just air and a magnetic field as protection. What we have found is that we need good shielding and to simulate gravity. So at the simplest, we need a lot of mass and we need the bit we live in to spin. Also, biology and technology are not particularly separate. Stuff like Dyson trees should not be written off. http://en.wikipedia.org/wiki/Dyson_tree http://en.wikipedia.org/wiki/Dyson_tree