From: "andy-nimmo"
To:
Sent: Wednesday, March 14, 2001 12:34 AM
Subject: Re: [spacesettlers] Re: why outer space?

> Hi Al,
>

Hi all,

> If you read "The High Frontier" by the late Professor Gerard K. O'Neill,
> you will see that he took this into account in his design. He balances
> the rotation by having two cylinders spinning in opposite directions,
> but attached. Several other scientists have endorsed his views.
>

I'm enjoying the opportunity presented by my physical presence in the United
States along this week and buying every interesting book that I can find. On
Sunday, I finally found "The Higher Frontier", a title that I tried to get
via overseas order at Amazon.com and Barnes and Nobles a couple of months
ago, but it was out-of-stock.

I still didn't start reading the book (my to-read stack is currently very
high, as one may imagine), but if I remember correctly the counter-rotating
pair of cylinders thing is also used to cancel the gyroscopic effect. In
that way, the pair can slowly rotate in a way that they are always pointing
to the sun. (A single cylinder would function as a gyro and point always in
the same direction - meaning that it would point away from the sun depending
on its location along the orbit.)

> Best wishes, Andy.
[snikt]

Best wishes, Lucio.

From: Dr. Omni [mailto:dromni@...]

On
Sunday, I finally found "The Higher Frontier", a title that I tried to get
via overseas order at Amazon.com and Barnes and Nobles a couple of months
ago, but it was out-of-stock.

I've been meaning to let the list know: The Space Frontier Foundation now
has a little website up specifically on the subject of the book "The High
Frontier". Tons of info on it and O'Neill, and some artwork too. This is a
project that Peter Thorpe started, and that I put the finishing touches on.

http://www.space-frontier.org/HighFrontier/

One note, though. The "Buy this book" links currently go to an on-line
purchasing systems that the SFF is soon going to dump, and it has not been
updated with the High Frontier info. As always, though, the book can be
purchased from the SSI catalog:

http://www.ssi.org/
http://www.ssi.org/high-frontier.html

http://www.ssi.org/catalog.html

The new addition has much new material by Dyson, Lewis, Tumlinson, and
others. Also, there's a bonus CD-ROM with MPEGs of presentations by O'Neill
and SSI, and PDFs of the two major NASA studies on space settlement.

Regards,

Mike Combs

From:
Dr. Omni [mailto:dromni@...]
On
Sunday, I finally found "The Higher Frontier", a title that I tried to get
via overseas order at Amazon.com and Barnes and Nobles a couple of months
ago, but it was out-of-stock.

I've been meaning to let the list know: The Space Frontier Foundation now has a little website up specifically on the subject of the book "The High Frontier". Tons of info on it and O'Neill, and some artwork too. This is a project that Peter Thorpe started, and that I put the finishing touches on.

http://www.space-frontier.org/HighFrontier/

One note, though. The "Buy this book" links currently go to an on-line purchasing systems that the SFF is soon going to dump, and it has not been updated with the High Frontier info. As always, though, the book can be purchased from the SSI catalog:

http://www.ssi.org/
http://www.ssi.org/high-frontier.html
http://www.ssi.org/catalog.html

The new addition has much new material by Dyson, Lewis, Tumlinson, and others. Also, there's a bonus CD-ROM with MPEGs of presentations by O'Neill and SSI, and PDFs of the two major NASA studies on space settlement.

Regards,
Mike Combs

"Dr. Omni" wrote:

> if I remember correctly the counter-rotating
> pair of cylinders thing is also used to cancel the gyroscopic effect. In
> that way, the pair can slowly rotate in a way that they are always pointing
> to the sun. (A single cylinder would function as a gyro and point always in
> the same direction - meaning that it would point away from the sun depending
> on its location along the orbit.)

Great in principle, but imagine the nitty-gritty difficulties of building and
operating such a system. Imagine the consequences when something goes wrong.
In general, I much prefer simple systems that do the right thing whether your
control system works or not. That's why a torusis probably better.

Al Globus
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.

I think we should:

1. Devote half of NASA's budget ($7 billion) to reaching NASA's 2020 goal of
reducing launch costs to Low-Earth-Orbit to $220/kg with a 0.01% failure rate.
This should enable space tourism. The resulting orbital hotels will need to
develop efficient orbital life support and other necessary technologies.

2. Build orbital space colonies. The materials in the largest asteroid are
sufficient for orbital colonies with a combined surface area about 500 times
greater than Earth's. Eros alone could make over ten thousand space colonies,
each with about about 10 square kilometers of 1g living area.

3. After a few generations of orbital living, people won't need their colony
to be near Sol. Then small groups of colonies with populations in the
tens-of-thousands can set out on multi-decade journeys to nearby stars.

Except the launch goals, none of this is even a little bit official.

Al Globus wrote:

>
> "Dr. Omni" wrote:
>
>> if I remember correctly the counter-rotating
>> pair of cylinders thing is also used to cancel the gyroscopic effect. In
>> that way, the pair can slowly rotate in a way that they are always pointing
>> to the sun. (A single cylinder would function as a gyro and point always in
>> the same direction - meaning that it would point away from the sun depending
>> on its location along the orbit.)

O'Neill mentioned that it is possible to keep the axis of rotation aligned with
the axis of the orbit and use a mirror to reflect light into the
habitat. You'd need to use counterweights to ensure stability though.

> Great in principle, but imagine the nitty-gritty difficulties of building and
> operating such a system. Imagine the consequences when something goes wrong.
> In general, I much prefer simple systems that do the right thing whether your
> control system works or not. That's why a torusis probably better.

Toruses bring their own problems, like how do you keep the torus pointing
towards the sun? Tori need twice the shielding mass requirements. Unless
you use active radiation shielding, but then you said you like simplicity...

For the record my favourite design is an orbital. Not quite
sure where I could get the unobtainium from to build it.
Anyone know off hand?

My second best design is probably a cylinder a few hundred meters across and
a few hundred or so meters wide. It would house an extended family or two
including grounds. Stability issues aren't going to be all that bad
in my opinion.

But it seems to me that any system is going to have a zillion nitty-gritty
difficulties WHATEVER shape it is. An aeroplane is often described
as a bunch of tradeoffs all flying in close formation; habitats aren't
going to be any different.

All habitats have to solve (roughly most important first although they
are all vitally important)

- direction stability to keep your solar collectors working- no energy and
you are quickly dead
- Air production
- lighting (including seasons/day night control)
- temperature control
- 'weather' patterns
- humidity control
- water purification and sewage treatment (unless you outsource it)
- food production (presumably, although importation is another possibility)
- travel to other habitats/planets (unless taxis are used)
- communications
- electricity
- leakage detection and correction
- gravity control
- cleaning
- cookery
- maintenance
- gardening/farming
- docking ports/air locks.
- finance
- trade
- defense

The thing is though, although this is an impressive list, it's only
slightly longer than the list of things I need to do to keep a
house going, it's just on a bigger scale.

It seems to me that the least of the problems are having to worry
about whether two cylinders are stable or unstable, as quite basic
overengineering can ensure that the really important stuff never
fails and the design can have fine tuning built into it to
remove any wobble before it really begins.

At the end of the day, habitat design is mainly about choice.
If Al doesn't like O'Neill cylinders he certainly doesn't have
to live in one.

Incidentally, if anyone wants to get some real insights
into space stations (closest thing we have to a space
settlement right now) you would do well to read some
of the books written by some of the people who have been
on MIR. I read the book by Colin Foale, Michael Foale's
father.

I found some interesting things I would never, ever have thought
of, like the fact that water condenses and forms a huge static
puddle on any cold surface in zero-g being one random example.

> --
> Al Globus
> aglobus@..., (650) 604-4404
> http://www.nas.nasa.gov/~globus/home.html

--
- Ian Woollard (ian.woollard@...)

"Is a planetary surface the right place for an expanding technological
civilization?"
- Gerard O'Neill

--- In spacesettlers@y..., Ian Woollard wrote:
> All habitats have to solve (roughly most important first although
they
> are all vitally important)
>
> - direction stability to keep your solar collectors working- no
energy and
> you are quickly dead

I agree, top priorities are orbital maintenance and power supply; at
this point in the list I would add "waste heat dissipation"

> - Air production
> - lighting (including seasons/day night control)
> - temperature control
> - 'weather' patterns

Weather considerations become important on a large-scale habitat like
an O'Neill cylinder, Bernal Sphere, Rama, etc., but chances are that
much smaller habitats will be built first, in the simplest design
possible - something like Space Island is likely to have tightly-
controlled "weather" in its hydroponics areas.

> - humidity control
> - water purification and sewage treatment (unless you outsource it)
> - food production (presumably, although importation is another
possibility)

Humidity control, air recycling, water purification and sewage
treatment, and food production should all be handled by the same
system, with wastes constantly being recycled in the hydroponics
area; as much as possible, a fully-contained ecosystem. We must have
learned quite a lot from BiosphereII, for instance which plants and
animals are best-suited to maintaining a complete food cycle in the
isolated environment.

> - travel to other habitats/planets (unless taxis are used)
> - communications
> - electricity
> - leakage detection and correction
> - gravity control
> - cleaning
> - cookery
> - maintenance
> - gardening/farming
> - docking ports/air locks.
> - finance
> - trade
> - defense
>
> The thing is though, although this is an impressive list, it's only
> slightly longer than the list of things I need to do to keep a
> house going, it's just on a bigger scale.
>

I think the list of things necessary for the operation of an orbital
settlement is not much different than the list necessary for the
operation of an aircraft carrier or nuclear submarine. Cost is
probably also comparable.

:) ed

We must have
> learned quite a lot from BiosphereII, for instance which plants and
> animals are best-suited to maintaining a complete food cycle in the
> isolated environment.
>
Out of curisoty, and because some said the same sentiment, is there
any data, papers, etc... that came out of the Biosphere experiments?

Bill

Ian Woollard wrote:

> Al Globus wrote:
>
> Toruses bring their own problems, like how do you keep the torus pointing
> towards the sun? Tori need twice the shielding mass requirements. Unless
> you use active radiation shielding, but then you said you like simplicity...

don't keep the torus pointing towards the sun. Use artificial light and power
satellites to beam energy to the colony.
Shielding mass does go up, but at least that doesn't give you the kinds of failure
modes instability brings.

>
> It seems to me that the least of the problems are having to worry
> about whether two cylinders are stable or unstable, as quite basic
> overengineering can ensure that the really important stuff never
> fails and the design can have fine tuning built into it to
> remove any wobble before it really begins.

I don't share your confidence. Basic physical stability is very important.
Consider earthquakes, mud slides, avalanches, etc. These are cases where basic
physical stability breaks down.

>
> At the end of the day, habitat design is mainly about choice.
> If Al doesn't like O'Neill cylinders he certainly doesn't have
> to live in one.

for living I like cylinders. They were my favorites for years.

>

Al Globus
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.

I think we should:

1. Devote half of NASA's budget ($7 billion) to reaching NASA's 2020 goal of
reducing launch costs to Low-Earth-Orbit to $220/kg with a 0.01% failure rate.
This should enable space tourism. The resulting orbital hotels will need to
develop efficient orbital life support and other necessary technologies.

2. Build orbital space colonies. The materials in the largest asteroid are
sufficient for orbital colonies with a combined surface area about 500 times
greater than Earth's. Eros alone could make over ten thousand space colonies,
each with about about 10 square kilometers of 1g living area.

3. After a few generations of orbital living, people won't need their colony
to be near Sol. Then small groups of colonies with populations in the
tens-of-thousands can set out on multi-decade journeys to nearby stars.

Except the launch goals, none of this is even a little bit official.

Ed Minchau wrote:

> -. We must have
> learned quite a lot from BiosphereII, for instance which plants and
> animals are best-suited to maintaining a complete food cycle in the
> isolated environment.
>

Actually, the lesson I took away from biosphere II was that you can pack
almost any largeish collection of animals and plants into a closed chamber
and you'll probably be okay. Consider this: the very first time they closed
the system and ran it for a year or so it more or less worked. There were
lots of problems, but the system didn't simply crash entirely -- which is
what I expected at the time. This kind of success is very unusual for any
truly new engineered system. Obviously, some species will die out and others
will expand. However, if you don't include anything you don't like and make
sure you can survive the elimination of any small set of species, my
hypothesis is that you should do okay. I think the biosphere II results
support this hypothesis, although obviously they don't prove it and much more
testing is necessary.

A small test of my own: my daughter put some soil and a flower plant in a
plastic container and closed the lid tightly. She gave it to me and I put it
in back of the house and ignored it for months. It's still alive. The
original flower died, but grasses came up and they seem to be reasonably
happy. I'm sure it's not completely gas tight, but it's tight enough to keep
the water vapor inside.

On Thu, 22 March 2001, Al Globus wrote:

>
At the science museum in Phoenix Arizona, they sell these sealed glass globes with some sort of shrimp and some simple plant in them. As long as you give them just enough light, and ignore them, they are supposed to chug along indefinately. NASA was supposed to have had something to do with them...

Mark

>
> A small test of my own: my daughter put some soil and a flower plant in a
> plastic container and closed the lid tightly. She gave it to me and I put it
> in back of the house and ignored it for months. It's still alive. The
> original flower died, but grasses came up and they seem to be reasonably
> happy. I'm sure it's not completely gas tight, but it's tight enough to keep
> the water vapor inside.
>

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