For a space station to generate artificial gravity in a human living condition would mean that it's so huge that not one country on it's own could supply the building materials. Then there would be the side effects of living in conditions where your body isn't experiencing constant gravity from head to toes.

Eh? You can have a rotating station of any size for artificial gravity. Inertia doesn't just stop working below a certain size. It's true that how fast you can spin a habitat without making everybody horribly sick is still an open question that needs further research - we don't actually know what those side effects would be. That doesn't make it automatically impossible.

Just how big do you think a space station needs to be for artificial gravity? Bearing in mind you might not even need Earth-level "gravity", Mars-level gravity might be enough. You might not even need a contiguous "wheel" station - consider two habitats connected by a tether, for instance.

Growing food for a large population would be impossible, simple crop rotation won't work in these kind of conditions. This would mean that the station would need to receive large amount of fresh soil or compost to feed the plants, the amount of fertilizer that would need to be stored is outrageous.

1. You got numbers to back that claim up?
2. You're assuming that "growing food" necessarily means "plants." It could mean genetically-engineered algae.
3. You're neglecting that hydroponics is a thing even here on Earth.

Growing the plants is a pain because you have to capture solar energy and use led lights, this is highly insufficient. You can't grow them on the surface of the station because the conditions would kill the plants.

Is there a reason you couldn't use windows or fibre-optic lighting? LEDs are not the only lighting method in existence.

Power would also be a problem because we can't even supply the people on earth with only solar panels,

Do you have proof of this claim? Especially as it relates to spacecraft, the vast majority of which are powered by solar panels. Spacecraft that aren't powered by solar panels are something of a rarity. :P

There are millions of other problems that make this a impossibility, the largest however is that such a station would need constant supplies from earth for the first few months until the ecosystem is balanced,The amount of resources for even only 10 000 people would be to expensive for any nation to support, you would also need a space launch for each day.

How big a supply ship are you assuming and what do you assume it would carry? To make so strong and specific a claim, you must have numbers. :)

We can't even keep a single astronaut in space for two measly years.

You do realize that the International Space Station has been continuously crewed since 1998? Multiple astronauts have had year-long space station missions now. The record for the longest space flight is currently 437 days, and that wasn't limited by the spacecraft, that was limited by desires not to subject the astronauts to too much weightlessness and presumably by the astronaut's desire to see their families again.

Is there a reason you couldn't use windows or fibre-optic lighting? LEDs are not the only lighting method in existence.

I would imagine windows of any significant size being somewhat problematic for at least two obvious reasons. First, there's not just light coming from the sun, but also one or the other high-energy proton. These are already an issue (cancer) in a sealed metal capsule. Imagine receiving them through a window.

Second, a window is considerably more vulnerable than a wall. If made from anything glass-like, it will shatter to a million pieces when the next dust-particule sized piece of debris that orbits Earth at something like 1/10c hits. If made from a polymer, it will be as strong, or stronger than steel, but it will either suffer massive material aging from the very high amount of ultraviolet light and break within a matter of some months (think polycarbonate), or it will not sufficiently protect anyone inside from lethal doses of UV light and protons. Or, both.

On the other hand, I don't think energy is such a big issue. Artificial light should be entirely feasible. Thanks to no atmosphere and no magnetosphere, there's plenty of energy floating around "for free" which you only need to collect. What are they doing in every sattelite or space station anyway? They're doing just that.

Even on Earth, the major part if not all, of our energy could come from the Sun... it is less of a technical problem, and more of a political/ideological thing. You would only need to place the panels where there is enough sun and where there are not so many people living (read as: e.g. sahara desert). And of course, the people living in between producer and consumer would have to agree on a "pipeline" of sorts. That would easily work from a technical point of view. But in practice, it doesn't even work well with gas pipelines. Look at the yearly melodrama with Russia, Ukraine, and Europe. Every winter.

Of course, nobody wants to be 100% dependant from the Arabs on everyday electricity, and nobody wants to risk another war coming up next year where your entire energy supply is located, or some coup d'etat with the new ruler cutting the line. On the other hand side, nobody wants to have a "pipeline" going through their country for someone else, not unless they pay outrageous money for it. And not for these people and those other people whom they don't like, either. And of course, it's such a nice thing to get attention because you can close the pipeline any time.

So, yeah... we put up panels where there is no sun, just like we build windmills where there is no wind. Surprised this doesn't work? That's inconsequential for the technological side, though.

Second, a window is considerably more vulnerable than a wall. If made from anything glass-like, it will shatter to a million pieces when the next dust-particule sized piece of debris that orbits Earth at something like 1/10c hits.

Good point, but you're overblowing this. Multiple crewed spacecraft windows have taken hits from micrometeroids and debris, but none have "shattered." Anything that would shatter a window would probably also do Bad Things to other materials. Also, no significant dust particle is likely to be moving 1/10 the speed of light. That's really, really fast. Certainly no orbital debris would be moving that fast - it wouldn't be in orbit if it were.

On the other hand, I don't think energy is such a big issue. Artificial light should be entirely feasible. Thanks to no atmosphere and no magnetosphere, there's plenty of energy floating around "for free" which you only need to collect. What are they doing in every sattelite or space station anyway? They're doing just that.

Most satellites do use solar panels. There's been a few nuclear-powered satellites, but they're in the minority nowadays - mostly outer solar system probes. There are even satellites that use solar electric propulsion. I'm not aware of any satellites that use fossil fuels for power.

It's definitely possible to put satellites into orbits that have continuous sunlight. There are even low orbits that are "sunsynchronous", meaning aligned to the terminator and so in continuous sunlight.

Eh? You can have a rotating station of any size for artificial gravity. Inertia doesn't just stop working below a certain size. It's true that how fast you can spin a habitat without making everybody horribly sick is still an open question that needs further research - we don't actually know what those side effects would be. That doesn't make it automatically impossible.

You are right, it doesn't need to be huge to generate gravity, high-G training uses a very small machine to do it. However creating a amount of gravity safe for people to live in is different.

Also thanks to high-G training we know it does more than make you feel a little sick. Just grab someone and spin them around by there hands, even this change in G is enough so that you will see the blood drain from there face to there feet; not having blood in your brain is bad.

Because we experience gravity almost equal in all parts of our body our system can't take a sudden change for too long. When there is more pull on your feet the hart needs to work harder to pump blood around, because liquids.

ust how big do you think a space station needs to be for artificial gravity? Bearing in mind you might not even need Earth-level "gravity", Mars-level gravity might be enough.

The estimate was a 100m radius, so play it safe and say 110m radius.(I can't find the paper, link if someone finds it)

edit: I researched it for a space station 3D model

You might not even need a contiguous "wheel" station - consider two habitats connected by a tether, for instance.

Smart idea, it would reduce the material needed. The largest downside of this would be that it would divide the people into two groups that couldn't reach each other. If you connected the two stations with a long tube, any one foolish enough to travel along it would experience more and more G force, then they would pass out and die unless saved.

Still a good idea though. ^_^

1. You got numbers to back that claim up? 2. You're assuming that "growing food" necessarily means "plants." It could mean genetically-engineered algae. 3. You're neglecting that hydroponics is a thing even here on Earth.

I come from a family with a long line of framers, I grew up around these people and picked up a thing or two: just know growing plants isn't a exact science. :)

OK, so when visiting my great great-aunt she would often calculate the cost as [(one a plant per person +4 plants)* the amount of days]. So one stalk of corn produces about 8-10 ears of corn, that is 2 for a group of 4. You don't only eat corn, so include tomatoes 4-6 on a plant; that is about one each. Now you are saying there is still 6 plants left to feed this group of 4 people, that is the cost for the meat say 400g-500g of mince; This is only rule of thumb however she was still using it the last time I visited.

I removed the price of the meat because I don't belief people in space will need such a luxury.

You have a good point about otter food sources however a good balanced died will be important in such a inclosure, a single sick person could kill everyone; also they need to remain functioning; normal crops will be needed.

Hydroponics doesn't change the fact that you need fertilizer, it just means you need more. Soil is good for plants because it regulates the amount of fertilizer they can convert into food at once, hydroponic plants get greedy and use as much as they can get meaning that it needs to be monitored by humans; the advantage is their greed allows for faster growth. Also large scale hydroponics can be expensive as it needs some metals.

Is there a reason you couldn't use windows or fibre-optic lighting? LEDs are not the only lighting method in existence.

A space station won't have a natural day/ night cycle and the sunlight is to harsh.

The test done for plant growth showed LEDs worked best and it isn't the bottle neck here, the solar panels are.

Do you have proof of this claim? Especially as it relates to spacecraft, the vast majority of which are powered by solar panels. Spacecraft that aren't powered by solar panels are something of a rarity.

Just Google the numbers a solar panel is about %60 better in space, it just isn't enough. True most spacecraft use solar, however it isn't a live long trip and there are only a few people on board, trained to deal with the lack of luxuries.

How big a supply ship are you assuming and what do you assume it would carry? To make so strong and specific a claim, you must have numbers.

Nothing precise however think of it, 110m radius, there just won't be space for storage or one harvest of food growth, you would also need to think of expansion as people will want children; there would be laws around that as there isn't a way to get more resources unless it's send. Like SeanMiddleditch said a moon base is more possible.

You do realize that the International Space Station has been continuously crewed since 1998? Multiple astronauts have had year-long space station missions now. The record for the longest space flight is currently 437 days, and that wasn't limited by the spacecraft, that was limited by desires not to subject the astronauts to too much weightlessness and presumably by the astronaut's desire to see their families again.

Yes, however the station is still part of earth, the astronauts receive constant supplies and get to go home; this is straining on them and is a job not a relaxing lifestyle.

Think of it as having your liver outside your body, it's still connected and functioning. Cutting the liver would mean it's death and the International would die if it stopped getting supplies from earth.

True I din't work out any thing to a precise point, however the scope that Asgardia is means that it isn't off by just a small precise amount of numbers; it's simply not in the scope of possibility in the live time of the people who registered on the site; unless all branches of science see constant miracle breakthroughs. :lol:

It would be more worth while to fund NASA's research.

Besides the "reason" for Asgardia is a fail safe for when earth dies, that's like locking a child in a basement and keeping them alive so that when you die they can take over the house.

There just isn't a valid reason for launching Asgardia, besides research, and research can be done in smaller and safer groups.

If you connected the two stations with a long tube, any one foolish enough to travel along it would experience more and more G force, then they would pass out and die unless saved.

Forces on a person in such a tube would diminish the closer they get to the center of rotation. You don't explode if you spin in your chair, do you?

1. A space station won't have a natural day/ night cycle
2. the sunlight is to harsh.

1. Can't you get around that by putting shutters on the window? It's not like the Earth's shadow would be much of a problem as long as you put the spacecraft in an orbit with continuous sunlight.
2. Car windows have UV filters on them - that's why "transition lenses" don't work in cars. Is there some reason this isn't possible for a space station?

Just Google the numbers a solar panel is about %60 better in space, it just isn't enough.

Just isn't enough for what? I was thinking more about the uncrewed solar-powered spacecraft that spend years sitting in orbit and run entirely on solar/batteries. They spend decades up there without even any way to replace the panels. A colony would absolutely have some way to replace panels.

You can also build pretty much arbitrarily large structures in orbit. You can make your panels really big because they don't have to support their own weight. Sure, you need to worry about attitude control and tidal forces, but it's still microgravity.

1. Hydroponics doesn't change the fact that you need fertilizer, it just means you need more.
2. hydroponic plants get greedy and use as much as they can get meaning that it needs to be monitored by humans;
3. Also large scale hydroponics can be expensive as it needs some metals.

1. Sure, but couldn't you synthesize the fertilizer? And soil has more than just fertilizer in it, right?
2. This is the 21st century, surely we can design an AI to monitor plant growth.
3. There's plenty of metals out there. Whole asteroids made of them. Lots on the Moon, too.

Yes, however the station is still part of earth, the astronauts receive constant supplies and get to go home; this is straining on them and is a job not a relaxing lifestyle.

Sure - right now. But ISS is only a stepping stone to better technology. I'm confident that these problems can be solved given sufficient attention and imagination.

If you connected the two stations with a long tube, any one foolish enough to travel along it would experience more and more G force, then they would pass out and die unless saved.

Forces on a person in such a tube would diminish the closer they get to the center of rotation. You don't explode if you spin in your chair, do you?

Yes, was just visualising it when I realized my mistake, you would need a ladder to reach it. This design could work.

1. Can't you get around that by putting shutters on the window? It's not like the Earth's shadow would be much of a problem as long as you put the spacecraft in an orbit with continuous sunlight. 2. Car windows have UV filters on them - that's why "transition lenses" don't work in cars. Is there some reason this isn't possible for a space station?

We don't have any thing that's this good yet simple UV filters wouldn't work and think what happens when it fades.

Also you would need all the surface for solar panels.

Just isn't enough for what? I was thinking more about the uncrewed solar-powered spacecraft that spend years sitting in orbit and run entirely on solar/batteries. They spend decades up there without even any way to replace the panels. A colony would absolutely have some way to replace panels. You can also build pretty much arbitrarily large structures in orbit. You can make your panels really big because they don't have to support their own weight.

Think of the human consumption of power, there is a reason people thought solar panels would never replace fossil fuels; it could in time just not yet.

Floating crafts could help however maintenance would be a pain.

The thing is these will be normal people using normal amounts of power, even if you reduced the power consumption by half it isn't enough; just think having internet for only half a day :o .

We don't have any thing that's this good yet simple UV filters wouldn't work and think what happens when it fades.

Maybe not yet. If the coating fades, it could be reapplied.

Also you would need all the surface for solar panels.

I'm not aware of any modern space station design concepts that put solar panels on the living module surfaces. That would be inefficient - there would always be panels pointing away from the sun. Solar panels on most crewed spacecraft (and on large uncrewed spacecraft, for that matter) are mounted on dedicated structures unfurled after launch. This is both to get more panel surface area than you could ever get by mounting the panels on the pressure hull and so that the panels can be aimed continuously at the sun. And again, the dedicated structures aren't restricted by gravity or the presence of ground/atmosphere.

The solar panels on the ISS are mounted on rotating hinges for this exact reason. Even the ones directly attached to crew modules. See diagram

Floating crafts could help however maintenance would be a pain.

It's in space - manual maintenance would always be a pain. Fortunately, robotics technology is marching along. There is one such demonstrator already on the ISS. Eventually, most EVAs would be conducted by dedicated robots, not humans.

The thing is these will be normal people using normal amounts of power, even if you reduced the power consumption by half it isn't enough

Again, what are your assumptions here?

I'm not aware of any modern space station design concepts that put solar panels on the living module surfaces. That would be inefficient - there would always be panels pointing away from the sun. Solar panels on most crewed spacecraft (and on large uncrewed spacecraft, for that matter) are mounted on dedicated structures unfurled after launch.

Yes, however the plants and panels need the sun, also this is a rotating structure.

Maybe not yet. If the coating fades, it could be reapplied.

Because if the critical conditions it would make more sense to replace the coating each day, the way they replace coating on walls when mining.

Still you need something better than we have today.

It's in space - manual maintenance would always be a pain. Fortunately, robotics technology is marching along. There is one such demonstrator already on the ISS. Eventually, most EVAs would be conducted by dedicated robots, not humans.

In time this project would be possible, no argument there. At the moment no one would risk loosing a robot to space, human live is so much cheaper.

Again, what are your assumptions here?

Normal consumption rates, not just household rates. Because street lights consumption would be replaced by the ship lights and life support and other important things would use what people are saving; I think that for the theoretical ship we should go for about 100 000 people and expansion up to 150 000 people.

I'm not aware of any modern space station design concepts that put solar panels on the living module surfaces. That would be inefficient - there would always be panels pointing away from the sun. Solar panels on most crewed spacecraft (and on large uncrewed spacecraft, for that matter) are mounted on dedicated structures unfurled after launch.

Yes, however the plants and panels need the sun, also this is a rotating structure.

Even if you put the panels on the rotating structure itself (ie. the whole station was rotating) and you didn't put the panels on a dedicated module, it should also be possible to point the axis of rotation towards the sun at all times. Remember, you're in space. :P

At the moment no one would risk loosing a robot to space, human live is so much cheaper.

UH. That is far from true in space matters. Human lives are seen as priceless. Safety is taken very seriously. Robot probes are seen as expendable - they're sent on one-way trips all the time. It's sad if a Mars probe disappears - if a spacecraft with humans on it disappears, there is mourning on an international scale (and the astronauts are eulogized as heroes), the entire program stands down for years, and the entire endeavour is questioned. It's much better to risk losing a robot that can be replaced (or repaired, or rebuilt) than a unique human life. That's kind of the entire point of the robot.

Human lives are not cheap. I'm frankly shocked that you would claim that human lives are less valuable than robot lives.

Normal consumption rates, not just household rates. Because street lights consumption would be replaced by the ship lights and life support and other important things would use what people are saving; I think that for the theoretical ship we should go for about 100 000 people and expansion up to 150 000 people.

Yes, but what are you assuming those rates are? I'm asking for numbers here. I don't think we can meaningfully discuss details beyond proposing ideas without numbers. :)