Scientific and technological advances have opened gateways to an
extraordinary future. Earth is no longer humanity's only home;
new habitats span the solar system on moons, planets, and in
between. Each is an engineering marvel – some are works of
art.Build An Asteroid Terrarium At least thirty kilometers on
its long axis. Any type will do—solid rock, rock and ice,
metallic, even iceballs, although each presents different
problems. Attach a self-replicating excavator assembly to one
end of the asteroid, and with it hollow out your asteroid along
its long axis. Ejection of the excavated material will represent
your best chance to reposition your terrarium, if you want it in
a different orbit. Store excess ejecta on the surface for later
use. Beyond the forward end of the cylinder, on the bow of your
new terrarium, attach a forward unit at the point of the long
axis. Eventually your terrarium will be spinning at a rotational
rate calculated to create the effect of gravity on the inner
surface of the interior cy