At ISDC 2015 I gave a talk entitled Space Settlement the Easy Way, by myself and Stephen Covey. The slides are now available athttp://space.alglobus.net/presentations/Easy.pdf which will eventually be replaced by a paper. The central idea is to build settlements close to Earth, make them small, and use tourism income to gradually build up hotel sizes until they are big enough to be settlements. This size is much smaller than previously thought because an extensive literature review finds that human rotation tolerance is much greater than believed by the space settlement community.

The talk takes advantage of the results of the two papers (see below) that suggest that orbital settlements can be hundreds of times less massive than we have thought and that equatorial (0 inclination, thats important) LEO below about 500 km is an excellent location for early space settlements. It appears that radiation shielding, 90+% of the mass of typical settlement designs, is probably unnecessary in equatorial LEO making launch from Earth very competitive with asteroidal or lunar materials. This result is supported by calculations using OLTARIS, NASAs web front end to very sophisticated space radiation codes.

The papers (preprints):

Space Settlement Population Rotation Tolerance, Al Globus and Theodore Hallhttp://space.alglobus.net/papers/RotationPaper.pdf

Orbital Space Settlement Radiation Shielding, Al Globus and Joe Strouthttp://space.alglobus.net/papers/RadiationPaper.pdf

Ad Astra!
http://space.alglobus.net/presentations/Easy.pdf
which will eventually be replaced by a paper. The central idea is to build settlements close to Earth, make them small, and use tourism income to gradually build up hotel sizes until they are big enough to be settlements. This size is much smaller than previously thought because an extensive literature review finds that human rotation tolerance is much greater than believed by the space settlement community.
The talk takes advantage of the results of the two papers (see below) that suggest that orbital settlements can be hundreds of times less massive than we have thought and that equatorial (0 inclination, thats important) LEO below about 500 km is an excellent location for early space settlements. It appears that radiation shielding, 90+% of the mass of typical settlement designs, is probably unnecessary in equatorial LEO making launch from Earth very competitive with asteroidal or lunar materials. This result is supported by calculations using OLTARIS, NASAs web front end to very sophisticated space radiation codes.
The papers (preprints):
Space Settlement Population Rotation Tolerance, Al Globus and Theodore Hall
http://space.alglobus.net/papers/RotationPaper.pdf
Orbital Space Settlement Radiation Shielding, Al Globus and Joe Strout
http://space.alglobus.net/papers/RadiationPaper.pdf
Ad Astra!

Yep, these recent findings are a real game-changer:

1. You need little or no radiation shielding in LEO.
2. Even in LEO, something the mass of a space colony has a very long
de-orbit time.
3. People can tolerate higher rotation rates than generally assumed.

Put together, it all means you can start small and cheap. So small and
cheap, in fact, that my High Frontier game can't even model colonies
that small!

Initial ones wouldn't really count as a space colony at all; they'd be
just rotating space stations, then hotels, then office/research parks,
etc. One day we'll look up, and start arguing about whether the first
true space settlement has already been built.

This very gradual path to space settlement is a huge departure from the
O'Neill-era plan to build a giant 10,000-person colony with lunar or
asteroid materials right off the bat. Incremental development is always
easier.

It also suggests to me that we should quit spending money on studying
how the body adapts to zero-G, and instead start spending it on rotating
structures. "Living in space" does NOT mean "living in microgravity" as
most people seem to believe, and it's silly to continue doing that when
we don't have to.

- Joe

Does NASA echo this viewpoint? NASA appears wedded to zero gravity.

And space hotel planners, will they think differently? ......

After a tiring 300km journey, there will be no time to relax because zero
gravity will have you in an uncontrollable spin. The trick is to find your
centre of mass, usually just behind your belly button. Once you learn how
to push off objects along an imaginary line running through this point, you
can stop spinning and move around.
http://www.bbc.com/future/story/20140718-what-is-it-like-on-a-space-hotel

Regards,
Selvaraj

On 1 June 2015 at 19:47, Joe Strout joe@... [spacesettlers] <
spacesettlers@yahoogroups.com> wrote:

> Yep, these recent findings are a real game-changer:
>
> 1. You need little or no radiation shielding in LEO.
> 2. Even in LEO, something the mass of a space colony has a very long
> de-orbit time.
> 3. People can tolerate higher rotation rates than generally assumed.
>
> Put together, it all means you can start small and cheap. So small and
> cheap, in fact, that my High Frontier game can't even model colonies
> that small!
>
> Initial ones wouldn't really count as a space colony at all; they'd be
> just rotating space stations, then hotels, then office/research parks,
> etc. One day we'll look up, and start arguing about whether the first
> true space settlement has already been built.
>
> This very gradual path to space settlement is a huge departure from the
> O'Neill-era plan to build a giant 10,000-person colony with lunar or
> asteroid materials right off the bat. Incremental development is always
> easier.
>
> It also suggests to me that we should quit spending money on studying
> how the body adapts to zero-G, and instead start spending it on rotating
> structures. "Living in space" does NOT mean "living in microgravity" as
> most people seem to believe, and it's silly to continue doing that when
> we don't have to.
>
> - Joe
>
> Yahoo Groups Links
>

And space hotel planners, will they think differently? ......
After a tiring 300km journey, there will be no time to relax because zero gravity will have you in an uncontrollable spin. The trick is to find your centre of mass, usually just behind your belly button. Once you learn how to push off objects along an imaginary line running through this point, you can stop spinning and move around.
http://www.bbc.com/future/story/20140718-what-is-it-like-on-a-space-hotel
Regards,
Selvaraj
On 1 June 2015 at 19:47, Joe Strout
joe@...
[spacesettlers]
<
spacesettlers@yahoogroups.com
>
Yep, these recent findings are a real game-changer:
1. You need little or no radiation shielding in LEO.
2. Even in LEO, something the mass of a space colony has a very long
de-orbit time.
3. People can tolerate higher rotation rates than generally assumed.
Put together, it all means you can start small and cheap. So small and
cheap, in fact, that my High Frontier game can't even model colonies
that small!
Initial ones wouldn't really count as a space colony at all; they'd be
just rotating space stations, then hotels, then office/research parks,
etc. One day we'll look up, and start arguing about whether the first
true space settlement has already been built.
This very gradual path to space settlement is a huge departure from the
O'Neill-era plan to build a giant 10,000-person colony with lunar or
asteroid materials right off the bat. Incremental development is always
easier.
It also suggests to me that we should quit spending money on studying
how the body adapts to zero-G, and instead start spending it on rotating
structures. "Living in space" does NOT mean "living in microgravity" as
most people seem to believe, and it's silly to continue doing that when
we don't have to.
- Joe
Yahoo Groups Links

Your email settings:
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> On Jul 5, 2015, at 8:05 AM, sraj sraj99@... [spacesettlers] wrote:
>
> Does NASA echo this viewpoint? NASA appears wedded to zero gravity.

No. This is a new discovery. Just made in the last few months. I havent even convinced NSS that this is the way to go much less NASA which for something big like this really means convincing Congress and the President, a major project.

>
> And space hotel planners, will they think differently?

I imagine that if the business takes off there will be a lot of creative thinking.

>
> After a tiring 300km journey, there will be no time to relax because zero gravity will have you in an uncontrollable spin. The trick is to find your centre of mass, usually just behind your belly button. Once you learn how to push off objects along an imaginary line running through this point, you can stop spinning and move around.
> http://www.bbc.com/future/story/20140718-what-is-it-like-on-a-space-hotel
>
> Regards,
> Selvaraj
>
> On 1 June 2015 at 19:47, Joe Strout joe@... [spacesettlers] > wrote:
> Yep, these recent findings are a real game-changer:
>
> 1. You need little or no radiation shielding in LEO.
> 2. Even in LEO, something the mass of a space colony has a very long
> de-orbit time.
> 3. People can tolerate higher rotation rates than generally assumed.
>
> Put together, it all means you can start small and cheap. So small and
> cheap, in fact, that my High Frontier game can't even model colonies
> that small!
>
> Initial ones wouldn't really count as a space colony at all; they'd be
> just rotating space stations, then hotels, then office/research parks,
> etc. One day we'll look up, and start arguing about whether the first
> true space settlement has already been built.
>
> This very gradual path to space settlement is a huge departure from the
> O'Neill-era plan to build a giant 10,000-person colony with lunar or
> asteroid materials right off the bat. Incremental development is always
> easier.
>
> It also suggests to me that we should quit spending money on studying
> how the body adapts to zero-G, and instead start spending it on rotating
> structures. "Living in space" does NOT mean "living in microgravity" as
> most people seem to believe, and it's silly to continue doing that when
> we don't have to.
>
> - Joe
>
> Yahoo Groups Links
>

sraj99@...m
[spacesettlers] <
spacesettlers@yahoogroups.com
> wrote:
Does NASA echo this viewpoint? NASA appears wedded to zero gravity.
No. This is a new discovery. Just made in the last few months. I havent even convinced NSS that this is the way to go much less NASA which for something big like this really means convincing Congress and the President, a major project.
And space hotel planners, will they think differently?
I imagine that if the business takes off there will be a lot of creative thinking.
After a tiring 300km journey, there will be no time to relax because zero gravity will have you in an uncontrollable spin. The trick is to find your centre of mass, usually just behind your belly button. Once you learn how to push off objects along an imaginary line running through this point, you can stop spinning and move around.
http://www.bbc.com/future/story/20140718-what-is-it-like-on-a-space-hotel
Regards,
Selvaraj
On 1 June 2015 at 19:47, Joe Strout

joe@...

[spacesettlers]

<
spacesettlers@yahoogroups.com
>

Yep, these recent findings are a real game-changer:
1. You need little or no radiation shielding in LEO.
2. Even in LEO, something the mass of a space colony has a very long
de-orbit time.
3. People can tolerate higher rotation rates than generally assumed.
Put together, it all means you can start small and cheap. So small and
cheap, in fact, that my High Frontier game can't even model colonies
that small!
Initial ones wouldn't really count as a space colony at all; they'd be
just rotating space stations, then hotels, then office/research parks,
etc. One day we'll look up, and start arguing about whether the first
true space settlement has already been built.
This very gradual path to space settlement is a huge departure from the
O'Neill-era plan to build a giant 10,000-person colony with lunar or
asteroid materials right off the bat. Incremental development is always
easier.
It also suggests to me that we should quit spending money on studying
how the body adapts to zero-G, and instead start spending it on rotating
structures. "Living in space" does NOT mean "living in microgravity" as
most people seem to believe, and it's silly to continue doing that when
we don't have to.
- Joe
Yahoo Groups Links

Your email settings:
Individual Email | Traditional
To change settings online go to:

To change settings via email:

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> On Jul 8, 2015, at 7:41 PM, sailorbarsoom@... [spacesettlers] wrote:
>
> As has been pointed out before:
> we know a whole lot about living at 1G;
> we know quite a bit about living at zero G;
> we know almost nothing about living at anything greater than zero and less than one;
> we know utterly nothing, nothing at all, about living at one G but cycling often between that, low G, and zero G.
>
Yes, but we do have lots of data for a pretty good analogue. Bed rest is physiologically pretty close to being in micro-g, particularly if you are a little head down. In fact, a lot of ground research is done using bed rest and the results transfer fairly well.

So, since we all sleep at least a few hours a night, there is reason to believe that going back and forth between 1 and 0 g wont be a big problem.

I suspect that in not-too-long space hotels will rotate at a low level to provide enough artificial gravity to make using the toilet reasonable easy (using a micro-g toilet requires quite a bit of training). Then it will be easy to get some data at (probably low) partial g.

>
> And it's about time we started studying those things. Let's see what sort of rotating space station could do that, with say twenty people aboard at any one time.I'm thinking a dumbbell design, but with "bells" at several levels along the "bar." In fact, it might be a good test of High Frontier at small sizes.
>

sailorbarsoom@...
[spacesettlers] <
spacesettlers@yahoogroups.com
> wrote:
As has been pointed out before:
we know a whole lot about living at 1G;
we know quite a bit about living at zero G;
we know almost nothing about living at anything greater than zero and less than one;
we know utterly nothing, nothing at all, about living at one G but cycling often between that, low G, and zero G.
Yes, but we do have lots of data for a pretty good analogue. Bed rest is physiologically pretty close to being in micro-g, particularly if you are a little head down. In fact, a lot of ground research is done using bed rest and the results transfer fairly well.
So, since we all sleep at least a few hours a night, there is reason to believe that going back and forth between 1 and 0 g wont be a big problem.
I suspect that in not-too-long space hotels will rotate at a low level to provide enough artificial gravity to make using the toilet reasonable easy (using a micro-g toilet requires quite a bit of training). Then it will be easy to get some data at (probably low) partial g.
And it's about time we started studying those things. Let's see what sort of rotating space station could do that, with say twenty people aboard at any one time.I'm thinking a dumbbell design, but with "bells" at several levels along the "bar." In fact, it might be a good test of High Frontier at small sizes.

Al Globus alglobus@... [spacesettlers] wrote:

> I suspect that in not-too-long space hotels will rotate at a low level
> to provide enough artificial gravity to make using the toilet reasonable
> easy (using a micro-g toilet requires quite a bit of training). Then it
> will be easy to get some data at (probably low) partial g.

If I were the hotelier, I'd go for lunar gravity (0.16 G or so). This
can be achieved with a 25-m radius spinning at 2.5 RPM, so is quite
easy, and then you get to put "It's just like being on the Moon!" in
your marketing materials.

(If we find that 2.5 RPM is bad for tourism, then at 50 m radius you
would spin at 1.7 RPM, and at 100 m radius, it'd be 1.2 RPM.)

You might also get some government/big-corporate customers who want to
train for lunar operations there, or researchers who want to study the
effects of long-term lunar habitation. So, lots of income opportunities.

In fact the practical value of the research we could do with a lunar
gravity research facility is so great, it quite boggles my mind that we
don't already have such a facility. People centuries from now are going
to look back at the dawn of spaceflight and be utterly baffled at the
back-asswards way we approached it, neglecting both the Moon and
artificial gravity for over half a century.

But I firmly believe that in the long run, fiercely stupid policies are
unsustainable... it'll all correct itself sooner or later, and we can
already see signs of this happening now.

Best,
- Joe

> On Jul 10, 2015, at 11:06 AM, Joe Strout joe@... [spacesettlers] wrote:
>
> Al Globus alglobus@... [spacesettlers] wrote:
>
> > I suspect that in not-too-long space hotels will rotate at a low level
> > to provide enough artificial gravity to make using the toilet reasonable
> > easy (using a micro-g toilet requires quite a bit of training). Then it
> > will be easy to get some data at (probably low) partial g.
>
> If I were the hotelier, I'd go for lunar gravity (0.16 G or so). This
> can be achieved with a 25-m radius spinning at 2.5 RPM, so is quite
> easy, and then you get to put "It's just like being on the Moon!" in
> your marketing materials.
>
> (If we find that 2.5 RPM is bad for tourism, then at 50 m radius you
> would spin at 1.7 RPM, and at 100 m radius, it'd be 1.2 RPM.)
>
Its probably ok, but if you go to 2 rpm it is almost certainly not much of a problem except for very susceptible individuals (for short term stays, for long stays 2.5 rpm should be just fine). See http://space.alglobus.net/papers/RotationPaper.pdf for the gory details of why this is probably so.

>
> You might also get some government/big-corporate customers who want to
> train for lunar operations there, or researchers who want to study the
> effects of long-term lunar habitation. So, lots of income opportunities.
>
> In fact the practical value of the research we could do with a lunar
> gravity research facility is so great, it quite boggles my mind that we
> don't already have such a facility. People centuries from now are going
> to look back at the dawn of spaceflight and be utterly baffled at the
> back-asswards way we approached it, neglecting both the Moon and
> artificial gravity for over half a century.
>
> But I firmly believe that in the long run, fiercely stupid policies are
> unsustainable... it'll all correct itself sooner or later, and we can
> already see signs of this happening now.
>
> Best,
> - Joe
>

joe@strout.net
[spacesettlers] <
spacesettlers@yahoogroups.com
> wrote:
Al Globus

alglobus@...

[spacesettlers] wrote:
> I suspect that in not-too-long space hotels will rotate at a low level
> to provide enough artificial gravity to make using the toilet reasonable
> easy (using a micro-g toilet requires quite a bit of training). Then it
> will be easy to get some data at (probably low) partial g.
If I were the hotelier, I'd go for lunar gravity (0.16 G or so). This

can be achieved with a 25-m radius spinning at 2.5 RPM, so is quite

easy, and then you get to put "It's just like being on the Moon!" in

your marketing materials.
(If we find that 2.5 RPM is bad for tourism, then at 50 m radius you

would spin at 1.7 RPM, and at 100 m radius, it'd be 1.2 RPM.)
Its probably ok, but if you go to 2 rpm it is almost certainly not much of a problem except for very susceptible individuals (for short term stays, for long stays 2.5 rpm should be just fine). See
http://space.alglobus.net/papers/RotationPaper.pdf
for the gory details of why this is probably so.
You might also get some government/big-corporate customers who want to

train for lunar operations there, or researchers who want to study the

effects of long-term lunar habitation. So, lots of income opportunities.
In fact the practical value of the research we could do with a lunar

gravity research facility is so great, it quite boggles my mind that we

don't already have such a facility. People centuries from now are going

to look back at the dawn of spaceflight and be utterly baffled at the

back-asswards way we approached it, neglecting both the Moon and

artificial gravity for over half a century.
But I firmly believe that in the long run, fiercely stupid policies are

unsustainable... it'll all correct itself sooner or later, and we can

already see signs of this happening now.
Best,
- Joe

Al Globus alglobus@... [spacesettlers] wrote:

>> If I were the hotelier, I'd go for lunar gravity (0.16 G or so). This
>> can be achieved with a 25-m radius spinning at 2.5 RPM, so is quite
>> easy, and then you get to put "It's just like being on the Moon!" in
>> your marketing materials.
>>
>> (If we find that 2.5 RPM is bad for tourism, then at 50 m radius you
>> would spin at 1.7 RPM, and at 100 m radius, it'd be 1.2 RPM.)
>>
> Its probably ok, but if you go to 2 rpm it is almost certainly not much
> of a problem except for very susceptible individuals (for short term
> stays, for long stays 2.5 rpm should be just fine). See
> http://space.alglobus.net/papers/RotationPaper.pdf for the gory details
> of why this is probably so.

Yep. And for completeness, lunar gravity at 2 RPM requires a radius of
about 36 m. For comparison, the half-length of the ISS is about 54 m.
So you could build a lunar-gravity hotel at 2 RPM that would be smaller
than the ISS, if you used a barbell shape.

Best,
- Joe