Asteroid use

--- Ian Woollard wrote:
> Marcel Williams wrote:
>
> > MW: Hollowing out asteroids would be a waste or
> > resources. You could probably build dozens of
> space
> > islands with with the materials you hollowed out
> from
> > the asteroid in the first place.
>
> Ian Woollard: This *isn't* an either-or thing. You
can do both.

MW: But why would you want to unless you enjoy doing
things their are economically unneccessary?

> Ian Woollard: And wasting resources? There's more
metal in Eros
> than can be mined from the entire surface of the
> earth. That's *ONE* asteroid and not a particularly
> big one.

MW: What's surprising about that?
>
> > MW: And industrializing
> > the surfaces of the Moon and Mars make far more
> > economic sense than trying to build large space
> > islands at this time.
>
> Ian Woollard: Actually the lunar surface is quite
hostile to
> equipment: the Apollo astronauts found that their
> suits were worn away after only a few hours. Lunar
> dust is *sharp*. That's a problem for any long
> stay scenario.
>
> The surface of the moon is a radioactive, airless,
> dusty, lifeless place.
>
MW: Which is why its an excellent place for dirty
industrialization. I think you're confusing
colonization with industrialization.

>Ian Woollard: The surface of mars is nearly as bad,
the atmosphere
> is less than 1% of the pressure of the earth- it's
> very radioactive too because the atmosphere blocks
> very little of the suns energy.
>
MW: Again, another place for dirty industrialization.
You can build as many plutonium and uranium nuclear
reactors as you want. And an excellent place for
those in the asteroid importation business to work on
the processing of small asteroids in Mars orbit.

> Ian Woollard: Either place you will have to live
underground.

MW: Actually, all you have to do is cover your
facility with about 5 meters of soil to protect you
from the most deadly cosmic rays. Habitat for Humanity
does that with sandbags in third world countries.
>
> Ian Woollard: Its actually safer in space- and a lot
easier to get
> to. And space has one thing you can't get anywhere
> else: microgravity.

MW: You'll still have the problem of cosmic radiation
and the problem of producing artifical gravity.
>
> Ian Woollard: Microgravity makes certain processes
possible. For
> example on earth we use something called
> electrophoresis to separate DNA. You pass a current
> through a material and it separates out. In space
> you
> can use electrophoresis to separate bulk materials
> like ore. It can't be done like that on earth
> because
> convection current form and ruin the process
> (that's why electrophoresis uses a gel in DNA
> work, but what gel can you use for molten rock?)
>
> Love to see you move 100 tonne blocks around. In
> space you can do it with one hand. Here, catch!
>

MW: Microgravity is also an excellent place for
producing metalic whiskers with tensile strengths 30
times that on the original metal. Microgravity is also
an excellent place to produce ultrathin aluminum for
my interplanetary lightsails. And a great place for
producing artificial diamonds. But you don't need an
O'Neill space colony to do that. All you need is a
small space platform which could be manned or
unmanned. And in most cases it would be preferable for
such facilities to be unmanned.

> And if you need gravity for something, you rotate
> stuff. No, not great big wheels. Think fluids and
> vortices. Think turning gravity on and off when you
> need it. Think low cost heating based on mirrors.
> Think about uses of hard vacuums, like vacuum tubes,
> televisions, mirrors, storage of food, vacuum
> deposition etc. etc.
>
> Think 24 hour sunshine. Think solar panels,
> think no-cost heating. Think no-cost cooling (vanes
> in shadow!)
>
MW: Think 2050 because that will be the earliest
you'll see for such a structure large enough for
people to want to spend the rest of their lives in
:-).

> > Ian Woollard: Their time will come. But their
> > time is definitely not in the next 20 or 30 years,
> > IMO.
>
> Ian Woollard: Oh well, if you say it. That's ok
then.
>
MW: Forgive me for pointing out that-- first-- you
have to build the mining and transportation
infrastructure before you can begin to economically
produce space islands that are worth living in. Back
in the late 1960s and early 1970s the US had the
capability of placing nearly 150 tonnes into low earth
orbit. Today we can barely place 25 tonnes into orbit
and NASA wants to replace this system with a vehicle
that can place an even smaller tonnage into space.

> Still, a wise man once said, almost exactly a
> century ago:
>
> "I confess that in 1901 I said to my brother...
> that man will not fly for fifty years..."
>
> - Wilbur Wright 1908
>
MW: Another wise man once said that Rome wasn't built
in a day. O'Neill thought the first space islands
could be built in the 1990's. It never happened
because it takes more than just dreams. It takes
political action. And many in the US congress thought
it was a nutty idea. The US congress also thought the
telegraph was a nutty in the 19th century. But
space islands would have been much closer to reality
if we had set up permanent industrial facilities on
the Moon and Mars during the 1980's and 1990s.
Islands in space will come but you have to build the
space industrial infrastructure-- first-- in order for
them to become a reality.

Marcel F. Williams
1/5/00