feedback needed on TEDx talk

I dont know if you want to use this, but it turns out that a combination of our radiation work and the discovery that 4-6 rpm is very doable means the first settlements might just be built in equatorial orbit below around 5-600 km, because thats the easiest option. Heres an abstract Im presenting at ISDC:

The first space settlement may grow organically out of a vigorous near-term space tourist industry. Here is why.

In the 1970s a series of studies at Stanford and NASA lead by Dr. Gerard ONeill of Princeton suggested the feasibility of building and living in free-space settlements (essentially gigantic spacecraft) [Johnson 1975, ONeill 1977]. Progress towards this dream has been slow in large part because the designs were very large and required extraterrestrial resources for even the first one. Such resources are hundreds of thousands (the Moon) or millions (the asteroids) of kilometers away.

Two new studies strongly suggest that free-space settlements in Low Earth Equatorial Orbit can be far less massive than previously thought, allowing initial materials to come from Earth. This vastly simplifies the construction and operation of the first space settlement because:

The settlement is much smaller (later ones can be bigger)
Thus extraterrestrial mining is unnecessary (although desirable)
The settlement is only a few hundred kilometers away from Earth
The settlement is only a small step beyond an advanced space hotel

The first of the two studies used sophisticated NASA radiation modeling software [Singleterry 2011] to show that in equatorial Earth orbits below about 550 km no radiation shielding is necessary [Globus 2014]. The Earth itself and the Earths magnetic fields protect this area from most space radiation. Radiation shielding is generally more than 90% of the mass of free-space settlement designs.

The second of these studies, currently in the final stages, examines the literature on human tolerance of rotation. Rotation is used in free-space settlement designs to provide something similar to Earth-normal gravity to the settlers. In the earlier designs it was assumed that a rotation rate of no more than 2 rpm is advisable, meaning that the diameter of the settlement must be about 450m to achieve Earth-normal pseudo gravity. Careful examination of the literature finds the 2 rpm limit to have little basis. In fact, the literature suggests that 4 rpm (and perhaps more) is fine, meaning a 112 m diameter is acceptable (4x less than traditional designs).

Assuming a cylinder similar to Kalpana One [Globus 2007], and using a very rough preliminary model of settlement mass, reducing the diameter from 450 to 112m leads to a 40x reduction in the mass. Using a similar model based on a torus leads to almost a 4x reduction in mass. Combined with eliminating the radiation shielding we get the 40-400x reduction in system mass. While this figure is soft due to the preliminary state of the mass models, if it is even in the ballpark this may permit building space settlements with materials launched from Earth in the not-too-distant future.

A 4 rpm settlement has dimensions about the same as the longest dimension of the International Space Station (ISS), which is currently in orbit. The ISS has been used as an extremely high-end ($20-50 million/visit) space hotel. One can easily imagine dedicated space hotels in the near future, and that these will grow larger and more luxurious over time if launch prices fall, which they have been lately. Some hotels may even rotate to provide a little artificial gravity if only to make bathroom trips easier. From there, only an increase in rotation rate to get 1g is necessary to deliver the first free-space settlement with a population of perhaps a few hundred.

Thus, the first space settlement may not come from a heroic effort by an elite band of adventurers, but rather be the natural outgrowth of a profitable commercial market complete with the luxurious amenities expected by high-end tourists.

References

[Globus 2007] Globus, Al, Nitin Arora, Ankur Bajoria, and Joe Strout. The Kalpana One Orbital Space Settlement Revised, April 2007.http://alglobus.net/NASAwork/papers/2007KalpanaOne.pdf.

[Globus 2014] Globus, Al, and Joe Strout. Orbital Space Settlement Radiation Shielding, October 2014. http://space.alglobus.net/papers/RadiationPaper2014.pdf.

[Johnson 1975] Johnson, Richard, and Charles Holbrow. Space Settlements: A Design Study. NASA, 1975. http://space.alglobus.net/75SummerStudy/Design.html.

[ONeill 1977] ONeill, Gerard K. Space Resources and Space Settlements - NASA SP-428. NASA, 1977. http://space.alglobus.net/spaceres/index.html.

[Singleterry 2011] Singleterry, R, S Blattnig, M Clowdsley, G Quallis, C Sandrige, L Simonsen, T Slaba, et al. OLTARIS: On-Line Tool for the Assessment of Radiation in Space. Acta Astronautica 68 (2011): 108697.

On Mar 6, 2015, at 6:55 AM, Joe Strout joe@... [spacesettlers] wrote:

> Hi gang,
>
> I've been invited to give a TEDx Youth talk about the High Frontier
> video game and orbital space colonies. The live audience will be about
> 2000 high schoolers, but of course they'll produce a video that will go
> up on the web and we hope receive millions of views. So this is a great
> opportunity to explain to the world why orbital colonies make sense.
> But it has to be short: 10 minutes is the length target. I've measured
> the text below at about 9 minutes, so there isn't a lot of room to spare.
>
> I'm primarily looking for feedback on the content: are there key points
> I have completely failed to mention, or points included that you think
> aren't worth mentioning? I'll also welcome suggestions on wording if
> you see a way to make it more inspirational. The text below is just the
> narrative; I didn't include the slides, but assume I'll have slides that
> support the narrative.
>
> Thanks!
> - Joe
>
> Hello, Im Joe Strout. I've got two boys, 10 and 14 years old, and
> we've been working for the past year on a space settlement simulation
> game called High Frontier. But there's more to it than just
> entertainment. I'd like to share with you some of the big ideas behind
> it, and why I think it's important.
> In the early days of space exploration, things proceeded very rapidly
> 12 YEARS from Sputnik to the first moon landing. People assumed this
> pace of change would continue, and that we would soon be moving into
> space in large numbers. So researchers looked carefully at whether the
> best site for our growing society is Earth, the Moon, Mars, some other
> planet, or somewhere else entirely. Surprisingly, they found the answer
> to be inescapable: the best site is somewhere else entirely.
> Researchers concluded that the best place for humanity to live in space
> is not on the surface of any planet or moon, but rather in
> free-floating, orbital space colonies. Numerous papers were written,
> and studies were done, working out the details. This was just before
> the Space Shuttle, which was expected to dramatically lower the cost to
> orbit, and cost analyses showed that we could have orbital cities of
> tens of thousands of people, perhaps by 1995 or so.
> Obviously, that didnt happen. The Shuttle turned out to be
> dramatically more expensive than envisioned, and funding for the space
> program was reduced. The energy crisis of the 1970s temporarily abated,
> reducing the need to look for clean, cheap energy such as space-based
> solar power. And so, we retreated to low-Earth orbit, going in circles
> for more than three decades.
> But now, things are changing again. Private enterprise is entering the
> rocket business in an aggressive way, with ventures like SpaceX bringing
> the cost to orbit down to the levels we were expecting in the 70s.
> Virgin Galactic is preparing to make routine passenger flights to the
> edge of space, Bigelow Aerospace has tested private inflatable space
> stations, and several companies are seriously proposing to mine
> near-Earth asteroids. And so, amidst all this renewed progress, people
> are starting to think again about colonizing space.
> But what destinations do people think about? The top of the list is
> always Mars. Mars holds a fascination for us, and has been a target of
> colonization dreams since the early days of spaceflight. Next up is the
> Moon, which has the unique advantage of being only a few days away, all
> the time. A few thinkers have considered Venus, which might support
> floating cities at just the right level in the atmosphere to have
> Earth-like temperatures and pressures. And then, so far down on the
> list that most people dont even give it any thought... orbital space
> colonies.
> So let's talk about those. How do they work, and should we be giving
> them more attention?
> First, let's look at gravity. We know that 1 Earth gravity, like what
> we're all sitting in right now, is good for us. And we know from years
> of living aboard space stations that zero gravity is not healthy for us.
> It causes bones and muscles to weaken, heart problems,
> immunodeficiency, and increased risk of things like kidney stones. But
> what do we know about intermediate levels of gravity, like the 1/3 G on
> Mars, or the 1/6 G of the Moon? Well, here's what we know:
> ...Nothing. Nobody has ever lived at any intermediate level of gravity
> for more than a few days, so we don't know the effects of these G levels
> on adults, much less children, who are likely to be much more
> susceptible to developmental problems. This is a big problem for
> planetary colonies, because you can't get Earthlike gravity anywhere
> except Earth and maybe Venus, but without children, you don't have a
> colony you have at best an outpost.
> An orbital space colony produces pseudogravity through rotation, just
> like amusement park rides some of you may have tried. The smaller the
> radius of rotation, the faster it has to spin to produce Earthlike
> gravity. A colony that's say, 1 km across only needs to spin 1.3 times
> per minute to produce 1 Earth gravity. Or, if we discover that smaller
> amounts of gravity are acceptable, we can either build smaller, or spin
> slower.
> In fact one cool thing about an orbital colony is that you can have many
> different levels of gravity at the same time; higher decks, closer to
> the spin axis, have proportionally less gravity. Maybe well find that
> elderly or injured residents are safer at 1/2 G; they can simply stay on
> a higher deck. And in the center, you can have zero-gravity sports and
> recreation, and still be home in time for dinner.
> OK then, what about radiation? Free space is filled with radiation from
> the Sun, and much harder radiation in the form of cosmic rays, which
> stream in from all directions. Here on Earth were protected largely by
> the Earths magnetic field, and secondarily by the tons of air above our
> heads. Mars, Venus, and the Moon have no significant magnetic field,
> and except for Venus, not much atmosphere either. So every time you
> walk outside there, youre dosing yourself with radiation. Youd have
> to stay underground most of the time to avoid problems like cataracts,
> cancer, and infertility.
> Orbital space colonies are built outside-in. Were probably going to
> want a couple meters of soil beneath our feet anyway, for supporting
> trees and grass and so on; and that alone provides ample shielding
> against space radiation. In fact in low Earth orbit, the background
> level of radiation would be even lower in a space colony than it is here
> on Earth. Outside of Earths magnetic field, you might need to add some
> additional shielding, but still, its much nicer to have that beneath
> your feet than over your head.
> Im going to touch only briefly on the day/night cycle. Obviously, we
> evolved with a 24-hour day; the Martian day is very similar, at about
> 24.6 hours, and that may be part of our fascination with Mars. But in a
> space colony, you would have exactly the day length that you want most
> likely, matching Earth. Daylight would either be sunlight reflected
> into the habitat through shield mirrors, or artificial lighting, but so
> far overhead that it produces an outdoorsy, daytime feel.
> You can tell by now that I see a lot of advantages in orbital colonies.
> As soon as you let go of your assumption that we need a planetary
> surface to live on, you quickly come to the conclusion that orbital
> space colonies are the place to be. In short: we can do better than Mars.
> This is why my sons and I are making High Frontier. Weve built it as
> realistic as possible the physics, radiation levels, energy balance,
> and everything else is based on real science. So players of the game
> arent just playing; theyre exploring a vast design space, and coming
> up with the solutions that might actually work. At the very least,
> theyre learning about an alternative to planetary colonies, and we hope
> that someday, some of those smart, educated players will help make it
> actually happen.
> When it does, it might unfold something like this. The little green
> dots you see here represent orbital space colonies, each one home to
> anywhere from 10,000 to 10 million men, women, and children. Recent
> work, based in part upon High Frontier, has shown that the best place to
> start is in low-Earth orbit, within the Earths magnetic shield. But
> well expand from there to higher Earth orbits, then orbits near the Moon.
> From there, orbital colonies around Mars might make sense, with its two
> moons providing materials. After that, well move rapidly into the
> asteroid belt, which contains half a million known objects, with
> estimates of around a billion objects at least 100 meters in diameter
> which doesnt sound like much, but a 100-meter asteroid weighs about 2
> million metric tons. So thats an awful lot of potential real estate,
> in the main belt alone. Then there are more asteroids in Jupiters
> orbit, and of course, the Jovian system itself, with 67 stable moons,
> not to mention rings massing about 10 billion tons.
> We could move on out to the Saturn system, which has similar resources;
> think of the view youd have out the windows there! And onward to
> Uranus, and Neptune, and then the Kuiper belt, with an estimated 70,000
> dwarf planets out in the cold and dark. And remember, unlike past human
> migrations, there are no ecosystems here; no natives that would be
> displaced. These are sterile chunks of ice and rock, just waiting for
> us to bring warmth and light and life. This greening of the solar
> system turning dead chunks of rock into millions of inside-out worlds
> with trees, birds, bugs, and people this is the bright future I see
> for us.
> And it all starts, here. Smart, enthusiastic kids playing a video game,
> where they get explore how and where to build space colonies, and how to
> run them when theyre built, how to balance the ecosystem, manage
> resources and budgets, and educate each generation. Thats why were
> building High Frontier. Thats why its not just a game.
> Thank you.
>

The first space settlement may grow organically out of a vigorous near-term space tourist industry. Here is why.
In the 1970s a series of studies at Stanford and NASA lead by Dr. Gerard ONeill of Princeton suggested the feasibility of building and living in free-space settlements (essentially gigantic spacecraft) [Johnson 1975, ONeill 1977]. Progress towards this dream has been slow in large part because the designs were very large and required extraterrestrial resources for even the first one. Such resources are hundreds of thousands (the Moon) or millions (the asteroids) of kilometers away.
Two new studies strongly suggest that free-space settlements in Low Earth Equatorial Orbit can be far less massive than previously thought, allowing initial materials to come from Earth. This vastly simplifies the construction and operation of the first space settlement because:
The settlement is much smaller (later ones can be bigger)
Thus extraterrestrial mining is unnecessary (although desirable)
The settlement is only a few hundred kilometers away from Earth
The settlement is only a small step beyond an advanced space hotel
The first of the two studies used sophisticated NASA radiation modeling software [Singleterry 2011] to show that in equatorial Earth orbits below about 550 km no radiation shielding is necessary [Globus 2014]. The Earth itself and the Earths magnetic fields protect this area from most space radiation. Radiation shielding is generally more than 90% of the mass of free-space settlement designs.
The second of these studies, currently in the final stages, examines the literature on human tolerance of rotation. Rotation is used in free-space settlement designs to provide something similar to Earth-normal gravity to the settlers. In the earlier designs it was assumed that a rotation rate of no more than 2 rpm is advisable, meaning that the diameter of the settlement must be about 450m to achieve Earth-normal pseudo gravity. Careful examination of the literature finds the 2 rpm limit to have little basis. In fact, the literature suggests that 4 rpm (and perhaps more) is fine, meaning a 112 m diameter is acceptable (4x less than traditional designs).
Assuming a cylinder similar to Kalpana One [Globus 2007], and using a very rough preliminary model of settlement mass, reducing the diameter from 450 to 112m leads to a 40x reduction in the mass. Using a similar model based on a torus leads to almost a 4x reduction in mass. Combined with eliminating the radiation shielding we get the 40-400x reduction in system mass. While this figure is soft due to the preliminary state of the mass models, if it is even in the ballpark this may permit building space settlements with materials launched from Earth in the not-too-distant future.
A 4 rpm settlement has dimensions about the same as the longest dimension of the International Space Station (ISS), which is currently in orbit. The ISS has been used as an extremely high-end ($20-50 million/visit) space hotel. One can easily imagine dedicated space hotels in the near future, and that these will grow larger and more luxurious over time if launch prices fall, which they have been lately. Some hotels may even rotate to provide a little artificial gravity if only to make bathroom trips easier. From there, only an increase in rotation rate to get 1g is necessary to deliver the first free-space settlement with a population of perhaps a few hundred.
Thus, the first space settlement may not come from a heroic effort by an elite band of adventurers, but rather be the natural outgrowth of a profitable commercial market complete with the luxurious amenities expected by high-end tourists.
References
[Globus 2007] Globus, Al, Nitin Arora, Ankur Bajoria, and Joe Strout. The Kalpana One Orbital Space Settlement Revised, April 2007.
http://alglobus.net/NASAwork/papers/2007KalpanaOne.pdf
.
[Globus 2014] Globus, Al, and Joe Strout. Orbital Space Settlement Radiation Shielding, October 2014.
http://space.alglobus.net/papers/RadiationPaper2014.pdf
.
[Johnson 1975] Johnson, Richard, and Charles Holbrow. Space Settlements: A Design Study. NASA, 1975.
http://space.alglobus.net/75SummerStudy/Design.html
.
[ONeill 1977] ONeill, Gerard K. Space Resources and Space Settlements - NASA SP-428. NASA, 1977.
http://space.alglobus.net/spaceres/index.html
.
[Singleterry 2011] Singleterry, R, S Blattnig, M Clowdsley, G Quallis, C Sandrige, L Simonsen, T Slaba, et al. OLTARIS: On-Line Tool for the Assessment of Radiation in Space. Acta Astronautica 68 (2011): 108697.
On Mar 6, 2015, at 6:55 AM, Joe Strout
joe@...
[spacesettlers] <
spacesettlers@yahoogroups.com
> wrote:
Hi gang,
I've been invited to give a TEDx Youth talk about the High Frontier

video game and orbital space colonies. The live audience will be about

2000 high schoolers, but of course they'll produce a video that will go

up on the web and we hope receive millions of views. So this is a great

opportunity to explain to the world why orbital colonies make sense.

But it has to be short: 10 minutes is the length target. I've measured

the text below at about 9 minutes, so there isn't a lot of room to spare.
I'm primarily looking for feedback on the content: are there key points

I have completely failed to mention, or points included that you think

aren't worth mentioning? I'll also welcome suggestions on wording if

you see a way to make it more inspirational. The text below is just the

narrative; I didn't include the slides, but assume I'll have slides that

support the narrative.
Thanks!
- Joe
Hello, Im Joe Strout. I've got two boys, 10 and 14 years old, and

we've been working for the past year on a space settlement simulation

game called High Frontier. But there's more to it than just

entertainment. I'd like to share with you some of the big ideas behind

it, and why I think it's important.
In the early days of space exploration, things proceeded very rapidly

12 YEARS from Sputnik to the first moon landing. People assumed this

pace of change would continue, and that we would soon be moving into

space in large numbers. So researchers looked carefully at whether the

best site for our growing society is Earth, the Moon, Mars, some other

planet, or somewhere else entirely. Surprisingly, they found the answer

to be inescapable: the best site is somewhere else entirely.
Researchers concluded that the best place for humanity to live in space

is not on the surface of any planet or moon, but rather in

free-floating, orbital space colonies. Numerous papers were written,

and studies were done, working out the details. This was just before

the Space Shuttle, which was expected to dramatically lower the cost to

orbit, and cost analyses showed that we could have orbital cities of

tens of thousands of people, perhaps by 1995 or so.
Obviously, that didnt happen. The Shuttle turned out to be

dramatically more expensive than envisioned, and funding for the space

program was reduced. The energy crisis of the 1970s temporarily abated,

reducing the need to look for clean, cheap energy such as space-based

solar power. And so, we retreated to low-Earth orbit, going in circles

for more than three decades.
But now, things are changing again. Private enterprise is entering the

rocket business in an aggressive way, with ventures like SpaceX bringing

the cost to orbit down to the levels we were expecting in the 70s.

Virgin Galactic is preparing to make routine passenger flights to the

edge of space, Bigelow Aerospace has tested private inflatable space

stations, and several companies are seriously proposing to mine

near-Earth asteroids. And so, amidst all this renewed progress, people

are starting to think again about colonizing space.
But what destinations do people think about? The top of the list is

always Mars. Mars holds a fascination for us, and has been a target of

colonization dreams since the early days of spaceflight. Next up is the

Moon, which has the unique advantage of being only a few days away, all

the time. A few thinkers have considered Venus, which might support

floating cities at just the right level in the atmosphere to have

Earth-like temperatures and pressures. And then, so far down on the

list that most people dont even give it any thought... orbital space

colonies.
So let's talk about those. How do they work, and should we be giving

them more attention?
First, let's look at gravity. We know that 1 Earth gravity, like what

we're all sitting in right now, is good for us. And we know from years

of living aboard space stations that zero gravity is not healthy for us.

It causes bones and muscles to weaken, heart problems,

immunodeficiency, and increased risk of things like kidney stones. But

what do we know about intermediate levels of gravity, like the 1/3 G on

Mars, or the 1/6 G of the Moon? Well, here's what we know:
...Nothing. Nobody has ever lived at any intermediate level of gravity

for more than a few days, so we don't know the effects of these G levels

on adults, much less children, who are likely to be much more

susceptible to developmental problems. This is a big problem for

planetary colonies, because you can't get Earthlike gravity anywhere

except Earth and maybe Venus, but without children, you don't have a

colony you have at best an outpost.
An orbital space colony produces pseudogravity through rotation, just

like amusement park rides some of you may have tried. The smaller the

radius of rotation, the faster it has to spin to produce Earthlike

gravity. A colony that's say, 1 km across only needs to spin 1.3 times

per minute to produce 1 Earth gravity. Or, if we discover that smaller

amounts of gravity are acceptable, we can either build smaller, or spin

slower.
In fact one cool thing about an orbital colony is that you can have many

different levels of gravity at the same time; higher decks, closer to

the spin axis, have proportionally less gravity. Maybe well find that

elderly or injured residents are safer at 1/2 G; they can simply stay on

a higher deck. And in the center, you can have zero-gravity sports and

recreation, and still be home in time for dinner.
OK then, what about radiation? Free space is filled with radiation from

the Sun, and much harder radiation in the form of cosmic rays, which

stream in from all directions. Here on Earth were protected largely by

the Earths magnetic field, and secondarily by the tons of air above our

heads. Mars, Venus, and the Moon have no significant magnetic field,

and except for Venus, not much atmosphere either. So every time you

walk outside there, youre dosing yourself with radiation. Youd have

to stay underground most of the time to avoid problems like cataracts,

cancer, and infertility.
Orbital space colonies are built outside-in. Were probably going to

want a couple meters of soil beneath our feet anyway, for supporting

trees and grass and so on; and that alone provides ample shielding

against space radiation. In fact in low Earth orbit, the background

level of radiation would be even lower in a space colony than it is here

on Earth. Outside of Earths magnetic field, you might need to add some

additional shielding, but still, its much nicer to have that beneath

your feet than over your head.
Im going to touch only briefly on the day/night cycle. Obviously, we

evolved with a 24-hour day; the Martian day is very similar, at about

24.6 hours, and that may be part of our fascination with Mars. But in a

space colony, you would have exactly the day length that you want most

likely, matching Earth. Daylight would either be sunlight reflected

into the habitat through shield mirrors, or artificial lighting, but so

far overhead that it produces an outdoorsy, daytime feel.
You can tell by now that I see a lot of advantages in orbital colonies.

As soon as you let go of your assumption that we need a planetary

surface to live on, you quickly come to the conclusion that orbital

space colonies are the place to be. In short: we can do better than Mars.
This is why my sons and I are making High Frontier. Weve built it as

realistic as possible the physics, radiation levels, energy balance,

and everything else is based on real science. So players of the game

arent just playing; theyre exploring a vast design space, and coming

up with the solutions that might actually work. At the very least,

theyre learning about an alternative to planetary colonies, and we hope

that someday, some of those smart, educated players will help make it

actually happen.
When it does, it might unfold something like this. The little green

dots you see here represent orbital space colonies, each one home to

anywhere from 10,000 to 10 million men, women, and children. Recent

work, based in part upon High Frontier, has shown that the best place to

start is in low-Earth orbit, within the Earths magnetic shield. But

well expand from there to higher Earth orbits, then orbits near the Moon.
From there, orbital colonies around Mars might make sense, with its two

moons providing materials. After that, well move rapidly into the

asteroid belt, which contains half a million known objects, with

estimates of around a billion objects at least 100 meters in diameter

which doesnt sound like much, but a 100-meter asteroid weighs about 2

million metric tons. So thats an awful lot of potential real estate,

in the main belt alone. Then there are more asteroids in Jupiters

orbit, and of course, the Jovian system itself, with 67 stable moons,

not to mention rings massing about 10 billion tons.
We could move on out to the Saturn system, which has similar resources;

think of the view youd have out the windows there! And onward to

Uranus, and Neptune, and then the Kuiper belt, with an estimated 70,000

dwarf planets out in the cold and dark. And remember, unlike past human

migrations, there are no ecosystems here; no natives that would be

displaced. These are sterile chunks of ice and rock, just waiting for

us to bring warmth and light and life. This greening of the solar

system turning dead chunks of rock into millions of inside-out worlds

with trees, birds, bugs, and people this is the bright future I see

for us.
And it all starts, here. Smart, enthusiastic kids playing a video game,

where they get explore how and where to build space colonies, and how to

run them when theyre built, how to balance the ecosystem, manage

resources and budgets, and educate each generation. Thats why were

building High Frontier. Thats why its not just a game.
Thank you.