I just realized that this message, which I posted on friday, hadn't
propagated, as I haven't received a copy. Perhaps some of you
have seen it, but presumably not everyone. -PV
---------- Forwarded message ----------
Date: Fri, 7 Dec 2001 19:00:36 -0800 (PST)
From: pete <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED]
Subject: FWk: Re: not so fast!
(Limiting my reply to FWk, to which I subscribe...)
On Fri, 07 Dec 2001, Steve Kurtz <[EMAIL PROTECTED]> wrote:
>Those calling for interplanetary colonisation as a 'solution' to human
>overpopulation might benefit from a reality check.
That idea would be limited to the physics illiterate: the systems
necessary to enable "CATS" (cheap access to space), such that
the energy and financial costs of lifting the mass corresponding
to the population excess beyond a comfortable 2 billion into space
could be manageable, are centuries away. Without an all out effort,
it is more like millennia. By that time we will have solved our problems
or had the earth solve them for us. (Making the target earth pop.
larger than 2 gigabodies just means that the yearly exportable surplus
is that much larger, and the costs that much larger).
>WHAT'S NEW Robert L. Park Friday, 07 Dec 01 Washington, DC
[...]
> At the request of NASA, a committee of the
>Institute of Health has examined the health issues surrounding
>long-duration space missions outside Earth's magnetosphere ("Safe
>Passage," National Academy Press, Washington, DC 2001, $80). The
>greatest risk is radiation exposure. There are no data on
>effects of the high-Z, high-energy particles that flood space and
>no suitable experimental facilities on Earth. Nor is there any
>way to predict solar outbursts with much higher radiation levels.
>Loss of bone density in zero gravity is so severe and NASA's
>"countermeasures" so marginally effective, that a mission to Mars
>with humans is unlikely to be undertaken unless a biological
>solution is found. Most surprising was the importance the report
>gives to the risk of psychological and social stress.
This is actually totally irrelevant to the issue of exporting
colonists. The issues are well understood, and the solutions
are well known. They just involve using a _lot_ of mass, and
so they require a mature infrastructure to achieve, which is
the same limitation I discussed above. Once the infrastructure
is in place, living and working in space will procede without
serious obstacle. In fact, the mass required to construct safe
space habitation and transportation can be extracted from
off-earth sources, thus avoiding the gravity-well penalty
inherent in bringing people off the planet, and so the infrastructure
required is less ambitious than that for shipping colonists
from earth.
-Pete Vincent
