Spinning [WAS] Island One, Two and Three

On Wed, 20 Oct 2004 22:50:10 +0530, sraj wrote:
> If Mars has water it certainly is worth settling.

Ahh! You positively *like* nuclear power!

> It has 0.4 Earth g; period of rotation is the same; solar illumination is enough for
> agriculture, even without intensifiers.

Quite possibly not. One of the things that failed in Biosphere II was
lack of light- the glass and support beams blocked out too much light,
as well as it being cloudy.

So, it isn't clear how well this really works. The only attempt to do
this, large scale on Earth failed.

Whilst it presumably won't be cloudy on Mars, the sun is only giving
half the sunlight to begin with, and the glass and support beams will
need to be very much thicker than Biosphere II to support 1 bar of
pressure difference.

Note that orbital habitats have similar problems in principle, however
they are likely to be closer to the Sun, above Earths atmosphere, and
they can position the beams to block less light as the habitat always
points directly towards the Sun.

> I don't fully understand the objection to planetary surfaces as space habitats.

It's more that they have advantages as well as disadvantages; and we
tend to forget the disadvantages.

The high escape velocity of Mars is a bad thing- exports to Earth are
going to be expensive from there, but exports to Earth from Earth
orbit and to Mars from Mars orbit are cheap. Exports to Earth from
Mars orbit are also going to be cheap.

Ultimately, exports tend to move money from the place being exported
to, from the place exported from. This seems to imply that Mars and
Earth are going to be poor in the very long term.

> Selvaraj

--
-Ian Woollard

"In theory there is no difference between theory and practice, but in
practice there is."
"a society in which people can do and say what they want will also
tend to be one in which the most efficient solutions win" - Paul
Graham