Another posting to spacesettlers.
Mike Combs
[mailto:spacesettlers@... On Behalf Of Xenophile
> Zubrin like to say that the smallest O'Neill colony is "a billion
tons."
snip
> I'm not sure where Zubrin gets his numbers.
Zubrin used the habitat mass number that got him the results he was
after, i.e. the economics of this whole thing are laughable, so quit
bringing it up and let's all go back to the idea of colonizing Mars.
What I tell people about the one billion ton Island 3 is to not worry
about it, because Island 3 won't get built by Earth people or the
current civilization. Island 3 will get built by a future space-based
civilization which will get its start in much smaller and more modest
habitats.
Zubrin pretended that an Earth-based corporation wishing to make SPS in
space would first have to build Island 3. He even avoided referring to
the structure as "Island 3" because the very name itself makes explicit
that it would not represent a first generation habitat (not even the
first generation of Earthlike habitats).
I used to wonder if I was the only one who thought Zubrin was not above
sometimes making a disingenuous argument to make things come out his
way. I've since heard many others voice much the same complaint, and in
various areas outside of Zubrin's rough treatment of O'Neill.
Regards,
Mike Combs
Made this posting to the spacesettlers maillist today, and then thought
it might be of interest to the SSI crowd.
Mike Combs
[mailto:spacesettlers@... On Behalf Of Dan Wylie-Sears
> How important is it to have the option of expanding the same colony,
> over a large size range, rather than building separate new colonies?
That seems to be a recurring point of contention between the original,
1970's concepts of space habitats, and more recent attempts by some to
update the concept. In the original designs, it was considered no big
deal that you had to build the entire habitat before you could move in,
and that when expansion was desired it would be accomplished by building
another habitat, rather than by attempting to somehow enlarge the
original structure.
I still don't have a problem with it. It's important to remember that
even Earth-like habitats would start out at the Bernal Sphere or
Stanford Torus level, so expansion would occur in discrete units of
10,000 population capacity. Even by the time we've moved up to the
Island 3 stage, it's occurred to me that one needn't necessarily develop
the entire interior of a cylinder at once. One might initially only
develop one end of each of the three valleys, leaving the biggest length
of each unfinished (perhaps provided with soil but left without
landscaping or other furnishing), and then only grow down the length of
each valley as population increases.
For some reason, some more recent thinkers seem to feel that it's
vitally important for the habitat to be able to grow in size but remain
a single unit. And (as Ralph touched on) I've even had it argued to me
that we must settle Mars rather than orbital space because on Mars we
can expand incrementally, whereas in orbit we must always build a
completely new habitat to grow. (I'm unconvinced that this outweighs
the many good points O'Neill made about orbital locations.)
Other than its discrete vs. incremental nature, I'm not sure what the
objection is to a new habitat vs. enlargement of an existing one. Maybe
people are thinking about the fact that going from one habitat to
another will always involve "space travel". But I've often visualized a
string of co-orbiting habitats interconnected by a maglev system. In
that case, I don't see a big advantage to enlargement of an existing
structure vs. replication of the small structure you're living in. In
fact, I can see the many small structures as being safer in the sense of
being more segmented and isolated.
Coming back to my "baton" suggestion before, I suppose one might start
out with a two-armed baton, and then later expand it to four arms. One
might even do it without halting the rotation, if one was cautious about
keeping construction workers and equipment from "falling off" (being
flung off, actually). Then four arms might later get extended to six
and then to eight. Somewhere along this process it would be
advantageous to install curving tunnels that connected each sphere to
its neighbor, so that one needn't go all the way up to the spin axis
just to get from one sphere to the other (and can remain under normal
gravity for the entire trip). So one might start out with a baton, and
in the long run wind up with a torus-shaped bead necklace.
Regards,
Mike Combs
Mike, ya'know it's been said, sometimes, in order to
make your dreams come true, you have to be a real
S.O.B.
Maybe we're just too rational to be really tough
SOBs,,,
make your dreams come true, you have to be a real
S.O.B.
Maybe we're just too rational to be really tough
SOBs,,, Well, even when I'm jousting on sci.space.policy, I try to remain civil. But on the other hand, I don't buy into the argument that all of us space advocates must be on the same page (read Mars) or nobody will get anything that they want. Nor do I consider Zubrin above criticism simply because he has made an undeniable contribution to the space advocacy community. Some of my Zubrin-critical writing has gotten at least as high as "Space Front", the newsletter of the Space Frontier Foundation. Strangely enough, one Mars advocate that I went round and round with for months on Usenet (the same fellow who invited me to compare a pile of Mars books with a pile of High Frontier books) suddenly turned around and invited me to submit one of my articles to his local Mars Society newsletter, the Sojourner. I wondered if he was getting frustrated at not being able to out-argue me, and had a vision of getting his fellow Mars advocates to rise up as oneagainst me. But I never heard a peep out of them. Either nobody had any criticisms to offer, or made sure to keep the conversation one-sided by not sharing them with me.
Mike Combs