On Oct 23, 9:16 am, Hop David wrote:


While CCs may be poor in some those materials, there are other asteroids
that aren't.

I acknowledge that one asteroid containing all these resources would be
rare. It would be hard for colonists on a metallic asteroid to use
nitrogen from an NEO on a different orbit.

On the other hand, there's no superhighways, oceans or rivers that can
be used for transportation on Mars. Transportation will be a substantial
barrier to self sufficiency on Mars as well as among the NEOs.


But once an initial presence is established on Mars, i.e. a
functioning town or other colony, constructing such (superhighways or
the equivalent) is a relatively straightforward project, in comparison
to establishing a viable interplanetary transport system between the
asteroids.