Growing crops in orbital colonies

From: spacesettlers@yahoogroups.com
[mailto:spacesettlers@yahoogroups.com] On Behalf Of vijay kumar

> i would like to know if it is possible to grow all the
> crops that we grow on earth in orbital colonies on a
> scale that is needed to support billions of people in
> the future in space habitats.

O'Neill certainly thought so. Detailed study of agriculture only went
up to the scale of Island 3 (O'Neill Cylinder) which would support a
population of 10 million. But there's no obvious reason why habitats
can't build more habitats until the off-planet population numbers into
the billions.

> i remember biosphere
> experiment proved a disaster and has there been any
> more such experiments.

One problem was that the biosphereans had an approach which was as much
guided by philosophical concerns as practical scientific and technical
matters. They attempted to recreate, in microcosm, /all/ of the
biospheres of Earth at once. A much more modest goal of creating one,
simple biosphere that was only as complicated as it needed to be to
support humans might have yielded better results.

> is it possible to convert the lunar soil and asteroid
> rocks into fertile soil to grow the crops does the
> technology exist already?

NASA did this with lunar soil back in the Apollo days. All that's
needed is application of nitrogen fertilizer (and it could be that
nitrogen may prove the gating element here) and the right kind of soil
microorganisms. The good news about the latter is that they're
self-replicating.

> and also is there really
> any water in moon and near earth asteroids to use for
> growing crops, drinking water needs and industrial uses.

We know of much greater amounts of water on the moon than were known in
O'Neill's day. It's a limited supply, but it should be enough to get us
started on the path to a space-dwelling society which can go further
afield for hydrogen.

There is a variety of asteroid which can be 10-20% water. In the outer
solar system are uncountable bodies which are as much as half water ice.

> if there is no sufficent water. what is the plan B? .
> should we manufacture the water or extract it from earth
> somehow?

Even in a worst-case scenario where mining water ice on the moon was for
some reason impractical, and for some unforeseeable reason we can't tap
into asteroidal resources in any short-term future, we probably would
not lift water up from the Earth, but only hydrogen. If refining
silicon and metals in space from ET resources, we would be producing
more oxygen than anything else. And 1 ton of hydrogen from Earth could
be combined with 8 tons of oxygen from the moon or a NEO to yield 9 tons
of water.

Regards,

Mike Combs