Asteroid use

--- In spacesettlers@egroups.com, "Combs, Mike"

> I wholeheartedly agree with you here. O'Neill type habitats
represent an
> incredible economy of mass.

Three big problems. First of all, constructed colonies have to be...
well, constructed (almost certainly on earth in the nearterm); &
flown at great cost to the final destination. Secondly, O'Neill style
colonies suffer from the problem that considerable additional
construction has to be done on orbit; & that some designs - like ISS -
may be uninhabitable until a certain criticial design mass has been
achieved.

Thirdly, a constructed O'Neill colony has only the in situ resources
you send to it; making expansion difficult without the establishment
of extraordinary space infrastructures.

Mining - which is really just tunnelling in human terms -
Earthgrazers with orbits resonant on Earth beats all of these
problems by:

a, sending only the technology required to build the colony; &
relying on in situ material & orbital location for the rest;

b, allowing the interior of the asteroid to be inhabited as its being
tunnelled; originally at microG - in the first mining tunnels along
the central axis of the asteroid; then at his artificl gravities as
habitation zones are dug out closer to the surface; &

c, leaving the colony with a literal rock to expand into; while also
creating new technology for export of the colony.

Mining is the investors' choice, therefore; construction th
engineers'.

Robert.