Colony ship to Alpha Centauri - The Motion Picture Concept b

[Ash Wyllie]

Rich Grise opined

On Wed, 05 Jan 2005 17:09:36 +0000, John Woodgate wrote:

I read in sci.electronics.design that Kryten <kryten_droid_obfusticator@
ntlworld.com> wrote (in <rUTCd.224$Wo1.18@newsfe5-gui.ntli.net&gt about
'Colony ship to Alpha Centauri - The Motion Picture Concept by A. Ahad',
on Wed, 5 Jan 2005:
Arthur C Clarke's story "Rendezvous with Rama" also had a huge
cylindrical spaceship.

Not the first one, either. Larry Niven's 'Confinement Asteroid' is
earlier. Construction begins in 2050.(;-)

I've heard that if you find a suitable metallic asteroid, turning it into
a sphere is almost trivial - you drill a core and fill this core with
water, or ice. Plug up the hole. Use a solar mirror to heat up the whole
thing to its melting point, at which time the water in the core will be
superheated steam. The metal melts, and Bwoop! the steam inflates it to an
iron/nickel bubble. Then just poke a hole and start building stuff on the
inside.

I'd really like to see a small proof of concept demo. Some asymmetry, or a
small flaw and your steam escapes to space.

I also read a story where somebody went and got a big ice asteroid, or
maybe a chunk of Saturn's rings, and just dropped it on Mars. You'd have
to get a new ice block every few hundred years, because the atmosphere
will eventually escape.

Niven again. Brennan, a protector, wanted to kill the Martians. It wasn't
interested in a usable atmospere.

And whoever tows the first iron/nickel/cobalt asteroid into a parking
orbit is going to become very, very rich. ;-)

Cheers!
Rich

-ash
Cthulhu in 2005!
Why wait for nature?

 

[Michael Ash]

In rec.arts.sf.science Rich Grise <richgrise@example.net> wrote:

I've just done a little anecdotal-grade experiment. Everybody's done the
"how long can you hold your breath" trick, with some people achieving
three or four minutes. But I thought, in vacuum, you don't have a lungful
of air. How closely can I simulate that condition by just simply exhaling
as hard, and completely, as I can?

So I did. I exhaled, and continued to exhale, forcing all of the air out
of my lungs that I was able to - since I'm in the atmosphere, there will
obviously be some quantity of air remaining. Oh, well, we'll have to
adjust our parameters. So I squeezed out as much as I could, and started
watching the clock.

At 45 seconds, I was impelled to breathe. I'm sure I could have gone
longer, but the "BREATHE NOW!" imperative from my limbic system was more
powerful than my desire to see if I got a buzz from it.

I guess the point is, you'd probably stay conscious for more than 15
seconds, but it would, like, hurt, like being strangled or something.
Shudder!

Unfortunately, your simulation didn't really match vacuum conditions very
well. The major difference is that when your lungs are full of nothing,
gases in the blood will actively *escape* back out into the lungs. The
blood going through your lungs will not only not be re-oxygenated, it will
be very efficiently de-oxygenated. The 15 seconds of consciousness comes
from the fact that this is about how long it takes blood to get from your
lungs to your brain. Once blood that's had all of the oxygen sucked out of
it reaches your brain, it's game over as far as remaining conscious goes.