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# 1910 bygalactonerd@... on Oct. 12, 2001, 5:53 p.m.
Member since 2021-10-03
I think that if anyone were to attack a space settlement, another space
settlement could just send an asteroid Earth's way. Asteroidal
deterrence (like nuclear deterrence) would probably prevent a space
settlement from being attacked. Thus, space settlements will probably be
safer than Earth from attacks.
# 1911 byGturner6PPC@... on Oct. 13, 2001, 12:23 a.m.
Member since 2021-10-03
There are a variety of attack methods to analyze. The obvious missle
attack has some problems, since the delta-V required to reach the
settlement is mostly spent during the trip out, and this makes the
incoming velocity fairly low. This velocity would be very low, when
compared to the small meteor strikes, which the station will no doubt
be designed to cope with. The kinetic energy of any non-nuclear
warhead will still likely be larger than its explosive chemical
component. But a double hull makes intact penetration difficult, as
any high velocity impact with the outer hull will probably possess
enough force to prematurely detonate the non-nuclear warhead.
Irregardless, the settlers will likely have many hours, if not days,
of prior warning, and unless the warhead contains the intelligence
and maneuverability to avoid counter-measures, such as positioning a
piece of large metal in its flight path. Additionally, hitting a
warhead with a warhead is getting much easier, and the settlers would
have hours to repeatedly try it.
someone who can pass the security checks. The potential for bio-
terrorism is probably less than a normal city, as the existing ships
and general manned transport equipment make it possible to quarantine
or evacuate large segments of the population. Additionally, if the
designers have any sense, they'd already have counted the passengers
on our 'Titanic' and made sure enough life boats are available.
Plus, in the event of a major hull rupture, I would imagine that each
dwelling, or group of dwellings, should have the equivalent of a
vacuum-shelter, capable of independently maintaining an atmosphere,
until help arrives.
Better attacks would be by having an agent ignite any type of
chemical fuels, already stored, to disrupt the station. In any large
zero-G hanger, one could grab the heaviest piece of metal available,
and start walking it faster and faster. Unlike on earch, a person
can keep putting kinetic energy into a single object, till it slams
throught a bulk-head, wall, or fuel-tank.
More clever attacks might be aimed at the stations food supply, with
any type of crop-disease, such as a blight, rust, or mold, or
extremely pernicious pest. This would provide an additional strain
on station resources, since the required pesticides might not be
immediately on hand. Arson is always a likely option, especially in
any type of confined environment.
Other attacks could be aimed at any large rotating bearings, inherent
in the design of some stations, which would use the station's own
rotational kinetic energy against itself. Any solar collectors that
are also in rotation could have their anchor points attacked, which
would plunge the station into a 'nuclear' winter, rendering it
uninhabitable for quite a long time. It would probably have to be
spun down, once the reflectors are rounded up and ready for re-
attachment.
Any retaliation with asteroid attacks against earth would probably be
politically impossible, and by the time any such attack can be
mounted and executed, which may be a year or more, any conflict would
probably be over.
Just some thoughts.
George Turner
Gturner6ppc@...
# 1912 byspider_boris@... on Oct. 13, 2001, 12:40 a.m.
Member since 2021-10-03
--- In spacesettlers@y..., Josh Kane wrote:
> I think that if anyone were to attack a space settlement, another
space
> settlement could just send an asteroid Earth's way. Asteroidal
> deterrence (like nuclear deterrence) would probably prevent a space
> settlement from being attacked. Thus, space settlements will
probably be
> safer than Earth from attacks.
opposed to the usually-discussed scenario of earth attacking a lone
space settlement? Sure, either could start lobbing big rocks down
the gravity well, which would piss off the earthers to no end, but
how about if they start attacking one another?
on another note: I have seen a few posts saying that nanotech could
be brought to bear to fight biological weapons in a space
settlement... however there are some problems with this idea:
1) nanotech is still in its infancy; we haven't yet written the
program that will allow us to design arbitrary nanostructures
2) once we are able to design these structures (and presumably, to
build them), then sure, a properly-programmed nanobot could be used
to fight bioweapons...and on the flipside, the same nanobots could be
weapons themselves. Have a problem with your neighbouring colony?
Just turn them into gray goo.
Having said that, it may turn out that space settlements may be the
only safe place to actually develop nanotech, as the possible gray
goo scenario would be limited to a single isolated structure.
:) ed
# 1913 bybestonnet_00@... on Oct. 13, 2001, 7:43 a.m.
Member since 2021-10-03
Thats assuming the person responsible can be found and would actually care if
they got killed.
# 1914 bybestonnet_00@... on Oct. 13, 2001, 7:56 a.m.
Member since 2021-10-03
--- Ed Minchau wrote:
> on another note: I have seen a few posts saying that nanotech could
> be brought to bear to fight biological weapons in a space
> settlement... however there are some problems with this idea:
> 1) nanotech is still in its infancy; we haven't yet written the
> program that will allow us to design arbitrary nanostructures
> 2) once we are able to design these structures (and presumably, to
> build them), then sure, a properly-programmed nanobot could be used
> to fight bioweapons...and on the flipside, the same nanobots could be
> weapons themselves. Have a problem with your neighbouring colony?
> Just turn them into gray goo.
goo to be able to destroy both the bio-weps (not that hard) and any gray goo
(requires somewhat advanced blue goo).
> Having said that, it may turn out that space settlements may be the
> only safe place to actually develop nanotech, as the possible gray
> goo scenario would be limited to a single isolated structure.
Developing in space would prevent them from destroying earth and if the place
they are being built on has a thermonuclear destruct system they wont be
getting off if they do become gray goo. The lab would likely be remote
controlled.
# 1915 byaglobus@... on Jan. 22, 2002, 7:44 p.m.
Member since 2021-10-03
The two nukes we dropped on Japan killed about 100,000 people each.
Assuming space colonies run around 10,000 per, each nuke will kill much
fewer people.
Al Globus
CSC at NASA Ames Research Center
aglobus@..., (650) 604-4404
http://www.nas.nasa.gov/~globus/home.html
The dinosaurs weren't spacefaring. We are. I don't think that's an
accident. Maybe we are life's taxi to the stars.
# 1916 bylucioc@... on Jan. 23, 2002, 7:37 p.m.
Member since 2021-10-03
From: "Al Globus"
To:
Sent: Tuesday, January 22, 2002 5:48 PM
Subject: Re: [spacesettlers] Vulnerability of Space Settlements to Attacks
> Assuming space colonies run around 10,000 per, each nuke will kill much
> fewer people.
>
I would not think that space colonies will stay at the "lower bound" of
10,000 people forever. I see no technical reasons to not build colonies for
100,000 people or more - indeed, if Earth-like interiors are dropped in
favor of a full occupation of the internal volume, even an Island One-sized
colony could house 100K people with a lot of room per capita.
However, I do concede that *economical* reasons may postpone the building of
big colonies to the far future. Human civilizations are not used to build a
whole city from scratch and then populate it; instead, we are used to grow
cities in incremental steps by adding new buildings as needed. We cannot do
the same thing with a space colony. And I would guess that are few (or none)
buildings in the world housing more than 10,000 people - and, although there
are projects for ber-buildings 2 Km high housing 100,000 people, those
projects never left their blueprints.
>
> --
> Al Globus
> CSC at NASA Ames Research Center
> aglobus@..., (650) 604-4404
> http://www.nas.nasa.gov/~globus/home.html
>
> The dinosaurs weren't spacefaring. We are. I don't think that's an
> accident. Maybe we are life's taxi to the stars.
[snikt]
Lucio Coelho
# 1917 byrmenich@... on Jan. 23, 2002, 9:02 p.m.
Member since 2021-10-03
Lucio de Souza Coelho wrote,
whole city from scratch and then populate it; instead, we are used to grow
cities in incremental steps by adding new buildings as needed. We cannot
do
the same thing with a space colony."
I sincerely hope that you are wrong. If we wait until such time as we
commit to building a home for 10,000+ people, then we will wait forever.
I think that collectively we need to move away from thinking about
"colonies", and instead start thinking about "worker housing" or
"construction shacks with worker dormitories". We need to think mentally
of the crew quarters on an oil rig as a model rather than the paintings of
the interior of Island One that we see in O'Neill's books --- the oil rig
analogy is far more likely to happen in the near term than the Island One
habitat. I'm not saying that Island One won't happen, but we are just
nowhere near that right now.
We MUST find a way to incrementally grow settlements in space. No entity
is going to take the financial risk of building a 10,000 person habitat
right after the starting gun has fired. We've got to find ways to
envision 10 people in space growning to 100 people in space growing to 500
people in space growing to 1000 people in space growing to ... ---- if we
can't envision the interim steps, then the 10,000-person habitat will
never materialize.
"And I would guess that are few (or none)
buildings in the world housing more than 10,000 people "
If I recall correctly, the World Trade Center towers in New York City held
25,000 people.
"and, although there
are projects for ber-buildings 2 Km high housing 100,000 people, those
projects never left their blueprints."
I think that post September 11th, there will be very little appetite for
moving these plans from blueprint to reality. Big structures, we now
know, have some risk aspects associated with them.
Ron
******
Lucio de Souza Coelho
01/23/02 02:26 PM
Please respond to spacesettlers
To:
cc:
Subject: Re: [spacesettlers] Vulnerability of Space Settlements to Attacks
From: "Al Globus"
To:
Sent: Tuesday, January 22, 2002 5:48 PM
Subject: Re: [spacesettlers] Vulnerability of Space Settlements to Attacks
> The two nukes we dropped on Japan killed about 100,000 people each.
> Assuming space colonies run around 10,000 per, each nuke will kill much
> fewer people.
>
I would not think that space colonies will stay at the "lower bound" of
10,000 people forever. I see no technical reasons to not build colonies
for
100,000 people or more - indeed, if Earth-like interiors are dropped in
favor of a full occupation of the internal volume, even an Island
One-sized
colony could house 100K people with a lot of room per capita.
However, I do concede that *economical* reasons may postpone the building
of
big colonies to the far future. Human civilizations are not used to build
a
whole city from scratch and then populate it; instead, we are used to grow
cities in incremental steps by adding new buildings as needed. We cannot
do
the same thing with a space colony. And I would guess that are few (or
none)
buildings in the world housing more than 10,000 people - and, although
there
are projects for ber-buildings 2 Km high housing 100,000 people, those
projects never left their blueprints.
>
> --
> Al Globus
> CSC at NASA Ames Research Center
> aglobus@..., (650) 604-4404
> http://www.nas.nasa.gov/~globus/home.html
>
> The dinosaurs weren't spacefaring. We are. I don't think that's an
> accident. Maybe we are life's taxi to the stars.
[snikt]
Lucio Coelho
# 1918 bylucioc@... on Jan. 23, 2002, 9:47 p.m.
Member since 2021-10-03
From:
To:
Sent: Wednesday, January 23, 2002 6:54 PM
Subject: Re: [spacesettlers] Vulnerability of Space Settlements to Attacks
I sincerely hope that you are wrong. If we wait until such time as we
commit to building a home for 10,000+ people, then we will wait forever.
I think that collectively we need to move away from thinking about
"colonies", and instead start thinking about "worker housing" or
"construction shacks with worker dormitories". We need to think mentally
of the crew quarters on an oil rig as a model rather than the paintings of
the interior of Island One that we see in O'Neill's books --- the oil rig
analogy is far more likely to happen in the near term than the Island One
habitat. I'm not saying that Island One won't happen, but we are just
nowhere near that right now.
We MUST find a way to incrementally grow settlements in space. No entity
is going to take the financial risk of building a 10,000 person habitat
right after the starting gun has fired. We've got to find ways to
envision 10 people in space growning to 100 people in space growing to 500
people in space growing to 1000 people in space growing to ... ---- if we
can't envision the interim steps, then the 10,000-person habitat will
never materialize.
I think that I my statement was unclear. When I said that a space colony
cannot be incrementally grown, I was saying that it is impossible (or
impractical at least) to make more room in a space colony once its
construction is finished and populated. When for instance an Island
One-sized colony is open to the colonists, it will have 65 millions cubic
meters of internal volume and there is nothing that you can do in order to
raise that number. (Although in theory you could de-spin the thing, build
another sphere connected to the first one and then put the structure
spinning again. As you can see, it is not the easiest operation in the
world, and the resulting assemblage is not the most stable thing in the
world either, I am afraid to say.)
However, beginning with extremely small colonies ("worker dormitories", as
you say) and then moving your population to larger structures as the first
ones get too cramped... That way that you mentioned is perfectly feasible,
and I think that that will be the path actually followed.
Unless, of course, medicine/technology overcomes the zero-g health hazards -
zero-g colonies could be expanded limitlessly in the same way that a
Earth-bounded city is.
If I recall correctly, the World Trade Center towers in New York City held
25,000 people.
Yes, but they were office buildings and I was thinking about more than
10,000 people *living* in a building. A *residential* building housing
25,000 people would have to be much larger than WTC - and much, much larger
if it was supposed to be a self-contained city, like the ber-buildings that
I mentioned - or like a space colony.
I think that post September 11th, there will be very little appetite for
moving these plans from blueprint to reality. Big structures, we now
know, have some risk aspects associated with them.
We always new that - WTC *was* built to resist airplane crashes, though not
of that magnitude. (And, still, my gut feeling is that a skyscraper built in
a "solid" style like the Empire States perhaps would not have crumbled to
dust like WTC. Modern skyscrapers are too light and tend to fall like a
castle of cards.) Anyhow, I agree that there are psychological aspects that
will remain for a while.
Ron
Lucio
# 1919 byian.woollard@... on Jan. 24, 2002, 1:26 a.m.
Member since 2021-10-03
rmenich@... wrote:
> I think that collectively we need to move away from thinking about
> "colonies", and instead start thinking about "worker housing" or
> "construction shacks with worker dormitories". We need to think mentally
> of the crew quarters on an oil rig as a model rather than the paintings of
> the interior of Island One that we see in O'Neill's books --- the oil rig
> analogy is far more likely to happen in the near term than the Island One
> habitat. I'm not saying that Island One won't happen, but we are just
> nowhere near that right now.
I don't agree with this sentiment. I think the analogy between
oil rigs and space settlement/habitats is a very poor one.
I think a much better analogy is to be made between space
settlement and buildings. We already have large buildings on
earth and there will be large buildings in space; but the vast
majority will be small I think.
When we get to asteroids, and they are much closer than they
appear to LEO, radiation shielding becomes essentially
costless, pressure vessels will cost, but not so much, energy
is 'free'; but then it doesn't cost so very much on earth when
you think about it.
Large constructs are always vulnerable one way or another- I'm
not talking about attack, but fire, accident, explosion,
disease and on- all these things are going to endanger large
single structures more than small; having all your eggs in a
single basket gives issues.
I prefer the smaller habitats sizes- their architecture is
every bit as interesting. How SMALL can you get and still be
nice to live?
> We MUST find a way to incrementally grow settlements in space. No entity
> is going to take the financial risk of building a 10,000 person habitat
> right after the starting gun has fired. We've got to find ways to
> envision 10 people in space growning to 100 people in space growing to 500
> people in space growing to 1000 people in space growing to ... ---- if we
> can't envision the interim steps, then the 10,000-person habitat will
> never materialize.
Your/we're missing a concept here: 'Space houses'
Raw materials being cheap, I think a 'space house' isn't going
to be out of most people's reach in space. The bottom line is
that people won't have to live or work in these huge Island
three's (but may choose to); but they are going to prefer much
smaller places by and large.
What systems do you need:
a) power (solar panels or solar generator)
b) temperature control (air conditioning)
c) light (windows)
d) gravity (rotation/tethers)
e) air recycling (CO2 -> O2 + C and trace element control,
dehumidifier)
f) comms
g) transport
h) garden
i) sewage (i.e. a cess tank)
j) water system
k) attitude control (keep the panels pointing at the sun-
basically trivial.)
l) kitchen
(Don't make the mistake of assuming that a house is a closed
system- it isn't.)
Think small- a family house is all we're talking about.
Transport is cheap. Energy is cheap. Mass is cheap. You get an
economy going- people do a job, get money, pay to keep their
habitat going. It's the same as a city, except in space. Other
people live near you; you can go see them in your space buggy,
shopping, or it is delivered.
You'd probably have a similar length list from ANY house on
earth, but the details are going to be different.
> Ron
> ******
--
- Ian Woollard (ian.woollard@...)
"Is a planetary surface the right place for an expanding
technological civilization?"
- Gerard O'Neill
# 1920 bybsarge@... on Jan. 24, 2002, 9:58 a.m.
Member since 2021-10-03
Lucio de Souza Coelho wrote:
> building of
> big colonies to the far future. Human civilizations are not used to
> build a
> whole city from scratch and then populate it; instead, we are used to grow
> cities in incremental steps by adding new buildings as needed. We
> cannot do
> the same thing with a space colony.
Start with a torus, build another one attached to it, then another to it
and so on, When you get enough put an
extra cylindrical shell around the outside enclose the holes in the
center open up some of the internal walls.
When the outer shell is placed make sure it has the windows inbuilt and
open up the torus's under them.
just one idea.
Another - why expand at all, build another one, set it up a short
distance away and run commuter vehicles between them. Rather than the
colony being one small station it becomes a collection of small
stations.We can expand as many as we want and still not be far from each
other.
B
# 1921 byaglobus@... on Jan. 24, 2002, 4:34 p.m.
Member since 2021-10-03
Actually, I strongly suspect that the first medium scale commerce
involving people in orbit will be tourism (right now tourism is the
*only* commerce involving people in orbit). Thus, minimalist living
quarters, such as worker housing, is a really bad idea. A tourist hotel
needs to be a nice as possible, with as many amenities as can be
provided. The main issue here is mass and maintenance -- anything with
low mass and maintenance that can make an orbital hotel cooler should be
provided.
> rmenich@... wrote:
>
> > Lucio de Souza Coelho wrote,
> > I think that collectively we need to move away from thinking about
> > "colonies", and instead start thinking about "worker housing" or
> > "construction shacks with worker dormitories". We need to think mentally
> > of the crew quarters on an oil rig as a model rather than the paintings of
> > the interior of Island One that we see in O'Neill's books --- the oil rig
> > analogy is far more likely to happen in the near term than the Island One
> > habitat. I'm not saying that Island One won't happen, but we are just
> > nowhere near that right now.
>
--
Al Globus
CSC at NASA Ames Research Center
aglobus@..., (650) 604-4404
http://www.nas.nasa.gov/~globus/home.html
The dinosaurs weren't spacefaring. We are. I don't think that's an
accident. Maybe we are life's taxi to the stars.
# 1922 byrmenich@... on Jan. 24, 2002, 4:49 p.m.
Member since 2021-10-03
The orbital hotel will be nice, but the quarters for the workers at the
orbital hotel --- those unfortunate folk who will have to clean up the
vomit --- will likely be spartan. The workers at the hotel will be the
only ones "living" off Earth for sizable lengths of time. The tourists
will come for a week or two and then leave.
*****
Al Globus
01/24/02 11:38 AM
Please respond to spacesettlers
To: spacesettlers@yahoogroups.com
cc:
Subject: Re: [spacesettlers] Vulnerability of Space Settlements to Attacks
Actually, I strongly suspect that the first medium scale commerce
involving people in orbit will be tourism (right now tourism is the
*only* commerce involving people in orbit). Thus, minimalist living
quarters, such as worker housing, is a really bad idea. A tourist hotel
needs to be a nice as possible, with as many amenities as can be
provided. The main issue here is mass and maintenance -- anything with
low mass and maintenance that can make an orbital hotel cooler should be
provided.
>
> rmenich@... wrote:
>
> > Lucio de Souza Coelho wrote,
> > I think that collectively we need to move away from thinking about
> > "colonies", and instead start thinking about "worker housing" or
> > "construction shacks with worker dormitories". We need to think
mentally
> > of the crew quarters on an oil rig as a model rather than the
paintings of
> > the interior of Island One that we see in O'Neill's books --- the oil
rig
> > analogy is far more likely to happen in the near term than the Island
One
> > habitat. I'm not saying that Island One won't happen, but we are
just
> > nowhere near that right now.
>
--
Al Globus
CSC at NASA Ames Research Center
aglobus@..., (650) 604-4404
http://www.nas.nasa.gov/~globus/home.html
The dinosaurs weren't spacefaring. We are. I don't think that's an
accident. Maybe we are life's taxi to the stars.
# 1923 bylucioc@... on Jan. 24, 2002, 10 p.m.
Member since 2021-10-03
From: "Brett Sargeant"
To:
Sent: Thursday, January 24, 2002 7:55 AM
Subject: Re: [spacesettlers] Vulnerability of Space Settlements to Attacks
> Start with a torus, build another one attached to it, then another to it
> and so on, When you get enough put an
> extra cylindrical shell around the outside enclose the holes in the
> center open up some of the internal walls.
> When the outer shell is placed make sure it has the windows inbuilt and
> open up the torus's under them.
>
> just one idea.
>
Okay, but you would have to either de-spin the first torus to build the
other one attached to it or to build the second torus separately and then
do a somewhat clumsy maneuver of spinning it and then connecting it to the
first torus when spin is equalized. Both cases seem unpractical to me. I do
prefer your second suggestion:
> Another - why expand at all, build another one, set it up a short
> distance away and run commuter vehicles between them. Rather than the
> colony being one small station it becomes a collection of small
> stations.We can expand as many as we want and still not be far from each
> other.
>
That's looks like my idea of a "colony matrix". You have a humongously big
2D, endlessly expansible hexagonal matrix facing sunwards. Each cell of the
matrix is occupied by an habitat of size and shape independent from the
others; you could have habitats that would just be "space houses" (like
those suggested by Ian Woollard) and the bigger ones could be "space
buildings". People can go from one little habitat to the other going to
their centers of rotation and then entering the "subway" (actually, an
"overway", if such word exists) of the Matrix, using transportation pods to
go to another place; or you could have free-flying "space cars". You would
just have to take an elevator, enter a car and then take another elevator at
the destiny - pretty much like moving through a big Earth-bounded city,
except that you will have no weight when in transit.
New cells could be added to the Matrix and old habitats in already-existent
cells could be demolished to give place to new ones. Much like a normal
city.
Of course the "colony matrix" flushes the romanticism of the High Frontier -
you have no beautiful curved landscapes and no seemingly endless open
spaces. Instead, you have something like a hive with relatively
claustrophobic habitats spinning in the cells. And so, what? The main
advantage of the High Frontier is practicality and economics, and those are
*reinforced* by the Colony Matrix architecture, I think; if you want
romanticism, then go terraform Mars.
> B
L
# 1924 bybsarge@... on Jan. 25, 2002, 10:38 a.m.
Member since 2021-10-03
Lucio de Souza Coelho wrote:
> other one attached to it or to build the second torus separately and then
> do a somewhat clumsy maneuver of spinning it and then connecting it to the
> first torus when spin is equalized. Both cases seem unpractical to me.
> I do
> prefer your second suggestion:
Build the new one in line with the spin axis of the older one, a short
distance away, spin it up, using small thrust along the axis move it
close to the other one, say 10 m for example then put in connecting
access tunnels. Don't see that it would be that clumsy, is just a
docking procedure writ large. Should be easy to match spin, and as long
as you keep the joining velocity tiny, then there shouldn't be any
trouble with moving them closer. If it is hard to put in the access
tunnels after spin up, then put them inplace before spinning up then you
only have to seal the join when they meet.
To turn it into a cylinder build the shell with one end open just a
little larger in diameter, again in line with the spin axis, and move it
in so it surrounds the torus's, then spin it up and make the joins.
Build the other end plate on the other side of the habitat spin it up
and join it up.
> That's looks like my idea of a "colony matrix". You have a humongously big
> 2D, endlessly expansible hexagonal matrix facing sunwards.
Why 2D ? why not 3D, space them correctly and you won't block the sunlight.
> Each cell of the
> matrix is occupied by an habitat of size and shape independent from the
> others; you could have habitats that would just be "space houses" (like
> those suggested by Ian Woollard) and the bigger ones could be "space
> buildings".
Two problems with small habitats ( I am guessing you are meaning for one
family unit an upwards ?)
1. You use the more material to provide the same volume of living
space, And you would probably have to shield each one to the same sort
of depth as an Island 1, which would make it cheaper to build an Island
one than a cluster of space houses for the same population.
2. Smaller spin radius, could lead to problems.
B
# 1925 bylucioc@... on Jan. 25, 2002, 6:50 p.m.
Member since 2021-10-03
From: "Brett Sargeant"
To:
Sent: Friday, January 25, 2002 8:35 AM
Subject: Re: [spacesettlers] Vulnerability of Space Settlements to Attacks
> Build the new one in line with the spin axis of the older one, a short
> distance away, spin it up, using small thrust along the axis move it
> close to the other one, say 10 m for example then put in connecting
> access tunnels. Don't see that it would be that clumsy, is just a
> docking procedure writ large. Should be easy to match spin, and as long
> as you keep the joining velocity tiny, then there shouldn't be any
> trouble with moving them closer. If it is hard to put in the access
> tunnels after spin up, then put them inplace before spinning up then you
> only have to seal the join when they meet.
>
Yes, it would be a docking procedure writ *too* large, and that's the
problem. Imagine someone trying to make soft contact between two
building-sized structures - but with way more inertia due to shielding.
AFAIK, no "docking procedure" that large has ever been tried, and therefore
I tend to be conservative and refuse this alternative in favor of disjoint
habitats. Of course one day something like that will be tried and maybe it
will even become a standard procedure. Until then...
However, even though that works, you would still have a structure that can
grow only linearly and in a planned way - while an Earth-based city can grow
in two (and, in a limited way, even three) dimensions and with no planning.
[snikt]
> Why 2D ? why not 3D, space them correctly and you won't block the
sunlight.
>
Any 3D lattice that does not block sunlight has to have a 2D projection
where its elements do not overlap. So, why not construct a 2D matrix from
the beginning and thus avoid extra consumption of materials?
Of course, if you are considering *really* big matrices - megameters in
diameter - then perhaps you would have to consider tidal effects, solar wind
pressure and other forces that may favor a 3D structure. That would also be
a plus for avoiding traffic jam between the habitats. But for
metropolis-sized matrices I think that a simple 2D grid would suffice.
[snikt]
> Two problems with small habitats ( I am guessing you are meaning for one
> family unit an upwards ?)
>
Indeed.
> 1. You use the more material to provide the same volume of living
> space, And you would probably have to shield each one to the same sort
> of depth as an Island 1, which would make it cheaper to build an Island
> one than a cluster of space houses for the same population.
>
It depends if shielding is expensive. If you're building your matrix around
an asteroid, for instance, shielding will be very cheap, I think. In
cislunar space, though, building an Island One would indeed be cheaper than
building smaller habitats to hold the same population - and, yet, smaller
habitats may still be preferred due to incremental growth capabilities of
such architecture.
> 2. Smaller spin radius, could lead to problems.
>
Not if you're using a dumbbell architecture.
> B
[snikt]
L
# 1926 byian.woollard@... on Jan. 26, 2002, 3:06 a.m.
Member since 2021-10-03
Lucio de Souza Coelho wrote:
> cislunar space, though, building an Island One would indeed be cheaper than
> building smaller habitats to hold the same population
The return delta-v for some of the NEO's is *very* low indeed;
by the time we are moving around in cislunar space we should
easily have the capability to return a bunch of rock to act as
shield. There's one NEO with a return delta-v of 150 mph(!) You
could take a tug over there and bring loads back with a pretty
trivial mass driver; or even easier if there are volatiles
there as well. It's probably a rare return trajectory, but you
could bring back tens of thousands of tonnes if you wanted.
See: http://www.permanent.com/a-overvw.htm
--
- Ian Woollard (ian.woollard@...)
"Is a planetary surface the right place for an expanding
technological civilization?"
- Gerard O'Neill
# 1927 byspider_boris@... on Jan. 29, 2002, 6:04 p.m.
Member since 2021-10-03
--- In spacesettlers@y..., Lucio de Souza Coelho wrote:
> However, I do concede that *economical* reasons may postpone the
building of
> big colonies to the far future. Human civilizations are not used to
build a
> whole city from scratch and then populate it; instead, we are used
to grow
> cities in incremental steps by adding new buildings as needed.
Or am I thinking of another Brazilian city?
> We cannot do
> the same thing with a space colony. And I would guess that are few
(or none)
> buildings in the world housing more than 10,000 people - and,
although there
> are projects for ber-buildings 2 Km high housing 100,000 people,
those
> projects never left their blueprints.
>
I can't think of a building housing 10000 or more right off the top
of my head, but there are plenty of really big buildings that would
hold many more people. Take West Edmonton Mall as an example - sure,
nobody is _housed_ there, but imagine that those 900 or so stores
were converted to apartments... how many people could you house in
5.2 million square feet?
:) ed
# 1928 bylucioc@... on Jan. 29, 2002, 7:40 p.m.
Member since 2021-10-03
From: "spider_boris"
To:
Sent: Tuesday, January 29, 2002 4:04 PM
Subject: [spacesettlers] Re: Vulnerability of Space Settlements to Attacks
Was not Brasilia planned from scratch and built in one fell swoop?
Or am I thinking of another Brazilian city?
Yes, Braslia indeed was planned from scratch and built in a non-stoop way
along a few years. Even though, that is just evidence favoring what I wrote:
"Human civilizations are not *used* to build a whole city from scratch and
then populate it..." (I added just now the stress in "used" for emphasis.)
There are thousands and thousands of cities in Brazil, and I know only two
cases among them where the cities were really built from scratch. That is,
planned cities are by far rare exceptions, and not the rule, and they have
their drawbacks, as explained below:
The more recent and better known planned Brazilian city is Braslia, and
that project alone drained a lot of money from the government safes and was
extremely criticized as a white elephant at the time (late 50's - Braslia
was finished in 1960). (I was born more than a decade after that, and even
though I also think that it was a waste of money.)
The other project that I know is my own city, Belo Horizonte, which was
built in the late 19th Century to be the new capital of my state. I don't
know how costly it was at the time and/or if the cost/benefit was heavily
criticized as in the case of Braslia. However, BH (as we often call it)
serves as an example of how a planned city can be *mis*planned:
- In first place, the dimensions of the city were extremely underestimated:
the planners thought that the city would never exceed 400,000 people;
however, in the first years after foundation, population growth rates
reached staggering values like 50%/year - mainly due to immigration, of
course - and that limit was quickly reached. Nowadays, we have more than 2
million people living in BH City and over 3 million in the Great BH. It is
interesting to see a city map, like the one at
http://www.pbh.gov.br/mapas/portal/fotos/bairroscomlistagem.gif, to see how
undersized the city was: in the map at the given URL, the originally planned
portion of the city is just part of the yellow area... Also, looking at
www.belohorizonte.com.br (where there is a beautiful navigable mosaic map
built with satellite and aerial images), one can clearly distinguish the
tiny planned part of the city (the "Centro", or Downtown) because it has
streets crossed in 90 and 45 degrees patterns, while all the city around has
mold-like street growth patterns.
- By the way, the 90-and-45-degrees-pattern used is simply awful for two
reasons: (a) it does not respect the topography (and the city is located in
a mountain region, as you can see in the satellite imagery) and (b) it is a
nightmare when it comes to car traffic. (Too bad that cars were still a
quaint luxury item in the 1890's...)
Therefore, *because* I know at least two examples of Earth-based planned
cities that were either too expensive or very ill-planned, I think that
future planners of space cities should be *very* careful. I would advocate
the use of the following policies:
- If you are building a small habitat, keep it really small, the size of a
big building at most.
- If you are building a huge habitat, build it as a "land area", and not as
a city. For instance, build it just as an empty air-filled cylindrical shell
and let the colonists build the city(ies) on demand in there. It would be a
"minimal intervention" policy.
I can't think of a building housing 10000 or more right off the top
of my head, but there are plenty of really big buildings that would
hold many more people. Take West Edmonton Mall as an example - sure,
nobody is _housed_ there, but imagine that those 900 or so stores
were converted to apartments... how many people could you house in
5.2 million square feet?
5.2 million square feet = 483,000 square meters (Sorry, I can't reason with
those American units. I would be lost in my visits to the US if not by the
fact that most products also display information in the Metric System. ;-)
Assuming 100 square meters per people, it could house 4,830 people.
But now I remember that there is indeed a building housing more than 5,000
people in So Paulo, for instance. I suspect that in Asia there are even
bigger housing structures. Maybe the 10,000 figure is not so outlandish...
:) ed
Lucio
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