A Better Space Station?

[holmec]

BTW I give little credence to the idea that a relatively small radius is detrimental to crew for an artificial gravity crewed craft. We have flown in planes, and experienced various G forces.

But for the sake of argument, lets test it in a real crewed space station with artificial gravity. That's a good reason as any to get one started.

 

[supag33k]

Well the concern would loading of any structure caused by rotational forces and rigidity of the rotating station.

The weight of the pieces would go up markedly, especially the central section, that would have to be assembled in space. Ideally the larger and heavier the diameter of the central hub mounting structure, the better the load carrying capacity to deal with these rotational forces.

The existing IIS could be reused in this newer station, just construct a 30 or 40 metre hub in space that is structural and not pressurised then connect the existing modules into place on the hub and join via temporary access tubes until the more permanent pieces are brought up.

Then the outer ring structure would have to be mostly in place before it could be spun up to around 2RPM or less.

The whole thing would be around 120 metres to 150 metres across and be several times heavier than the current ISS - and yes it really comes down to both big $$$ and lots of lifting capacity.

Also the new station should be in a higher orbit with less maintenance involved.

 

[zenofjazz]

The idea of an extruded aluminum skin wrapped around an inflatable torus is an excellent idea. The torus can be sized to fit in whatever launch vehicle is available at launch time. The trick is to avoid having to launch EVERYTHING from Earth's surface.

The best way to decrease the cost of this exercise is to do this in a repeatable, reproducible fashion.

The single biggest cost is currently launch costs. The fastest way to decrease launch costs is to launch from someplace with lower gravity. The nearest place where we can find the resources for this type of exercise is the moon. The lunar surface is rich with the following resources: Silicon, Oxygen, Aluminum, Iron, Magnesium, Calcium, Titanium, Hydrogen, Helium, Argon, Nitrogen, Neon, Krypton, and Carbon.

So, what can we do with these resources? Well, first off, silicon, and various other materials can be used to create solar cells. Not necessarily high efficiency solar cells. But, if they can be manufactured in-place, on the moon, efficiency doesn't matter, because we simply trade # of cells for efficiency. Secondly, we can build capacitors. Big capacitors. And thirdly, we can build a rail-gun for launching refined materials back to earth-orbit. Fourth, we build solar powered smelters, capable of being used to refine aluminum, iron, magnesium, and titanium. Purified, and extruded as wire, they can be used on-orbit for a variety of purposes.

Additionally, Iron can be processed into high tensile strength steel, formed into functional length trusses, and also boosted to Earth orbit. While many of these processes may require human intervention, to set up, and get running, automation should allow for a limited manned presence on the moon, while a stream of prepared resources moves from the moon's surface to Earth Orbit.

By boosting the torus up, deflated, and then inflating it on orbit, it would be possible to wrap it with a combination of carbon fibers, and aluminum wire, to provide extremely high strength exterior armor. Once the torus is wrapped, trusses can be added, to provide mount points for all necessary fittings. The wrapping process could be highly automated, with relatively simple robotic wrappers slowly traversing the exterior of the torus, until sufficient layers of carbon fiber, and aluminum have been deposited. Alternatively, a layer of expanding foam could be laid down first, then carbon fiber, then another layer of foam, and a final layer of aluminum wire.

This would allow for some protection from micro-meteorite impacts.

Once the structure is completed, solar arrays (again from lunar resources) could be arrayed around the outer rim of the station, giving a sun-flower look, and leaving the central hub area free for maneuvering.

By having a two-part central hub, with one portion rotating with the station, and the remainder stationary for docking maneuvers, it should be possible to simplify the interface between.

Any zero gravity labs can be tethered nearby, with the understanding that access is by way of spacesuit. That way they will not be disturbed by any vibrations caused by the occupants moving within the station.

Finally, expansion comes in one of two ways. A second ring can be created (with a larger diameter) away from the current station, and flown into place when completed, providing a bulls-eye type arrangement, once attached, or a second torus can be inflated, and wrapped, adjacent to the first.

In either case, accessways would be necessary, but should be a relatively simple exercise, after all we've done so far.

The advantage with the "bulls-eye" arrangement is that you can have multiple levels of gravity on the station, for example, a lower gravity section, for those who would be unable to survive at full earth gravity.

 

[Mee_n_Mac]

The trick is to avoid having to launch EVERYTHING from Earth's surface.

The best way to decrease the cost of this exercise is to do this in a repeatable, reproducible fashion.

The single biggest cost is currently launch costs. The fastest way to decrease launch costs is to launch from someplace with lower gravity. The nearest place where we can find the resources for this type of exercise is the moon. The lunar surface is rich with the following resources: Silicon, Oxygen, Aluminum, Iron, Magnesium, Calcium, Titanium, Hydrogen, Helium, Argon, Nitrogen, Neon, Krypton, and Carbon.
{snip}

I agree whole-heartedly with the above. So why have a mammoth space station ? Why not a Moonbase instead ? (not to go completely OT here but .....)

 

[zenofjazz]

The trick is to avoid having to launch EVERYTHING from Earth's surface.

The best way to decrease the cost of this exercise is to do this in a repeatable, reproducible fashion.

The single biggest cost is currently launch costs. The fastest way to decrease launch costs is to launch from someplace with lower gravity. The nearest place where we can find the resources for this type of exercise is the moon. The lunar surface is rich with the following resources: Silicon, Oxygen, Aluminum, Iron, Magnesium, Calcium, Titanium, Hydrogen, Helium, Argon, Nitrogen, Neon, Krypton, and Carbon.
{snip}

I agree whole-heartedly with the above. So why have a mammoth space station ? Why not a Moonbase instead ? (not to go completely OT here but .....)

Microgravity is VERY difficult to achieve on the lunar surface. An Earth orbit station is also very useful for many things.
1) orbital shipyard (good place to build ships, with all those lunar sourced resources)
2) lab space, zero-G, and other details.
3) tourist attraction (with sufficiently low launch costs)
4) jumping off point to other locations
5) additional lab space ideas.. quarantine station for biological research that would be too dangerous for on-earth work.
6) fuel depot, supply depot, etc.

These of course, assume that you have places to go, things to do, all over the solar system. Once you're out of the Earth's gravity well, you're 1/2 way to everywhere. Using the Lunar surface for resources, is a good start. Asteroid belt for additional resources. You may have noticed that Hydrogen and Oxygen are both plentiful on the moon. That's life support gasses, and water. All you have to do is liberate them from the surface. Sufficient heat, will do that.

You say you need to be able to grow hydroponic plants for food/life support purposes? Nitrogen is plentiful, too.

So, what can we do, on orbit? Solar power satellites... Beaming power down to the surface of the Earth, helping to get rid of Coal fired plants, and other less than perfect solutions to our energy needs.

We can capture asteroids, and mine them for resources scarce on the moon.

A moon base? Why stop there?

In the 70's the Nixon administration told NASA you can have your space station, or you can have your truck (the Shuttle) to get there. See what came from that delay?

 

[MasterMiend]

There are a lot of good ideas out there, but engineers had to design this station 30 years ago using reliable concepts. With a rotating station, there are several problems:
Coriolis effect- still unknown at this point. How will astronauts react? Why spend $50 Billion just to find it doesn't work? We can investigate this later.
Balance - If the mass in any place changes, by just a little, the whole station can begin to violently wobble. Just having astronauts walk around the station would not be tolerable without some sort of active balance system (read high maintenance, prone to failure, dangerous). Loading and unloading people and supplies would be very difficult.
Vibration - most of the arguments for building the station was as a research center, but the experiments require microgravity and extreme stability. A rotating station would not provide either. There would have to be a portion of the station that was not rotating, that would remain fixed in its orientation requiring motors (read high maintenance again).
Solar power - solar panels require a fixed platform facing the sun at all times. In order to get power, you need to mount a counter-rotating strut permanently fixed to the hub of the station.
Safety - all of the other issues aside, a rotating ring or wheel is inherently unsafe since the only point of egress is through the hub which also happens to be the only place to mount experiments, for the solar power panel struts, and a docking ring.
Docking - A hard dock in which two objects are physically connected so people can transfer easily between the two in a shirtsleeves environment is preferable to a soft dock

 

[MasterMiend]

Continued:

Weight - is another issue. A rotating structure would require much more strength in structural members which complicates design and launch requirements.

Flexibility - as mass shifts in a wheel, the wheel gets out of shape requiring a lot of flexibility in joints between units and components.

Attitude adjustment - how could the station's orbit be modified. Again, placing rockets and propellant around the central hub doesn't sound like a great idea to me. They would also need to be refueled. A visiting rocket would have to push ecxactly along the axis... Listen, this is getting too complicated.

Finally, if the rotating docking hub seizes up, goodbye. No hard docking, maybe not even soft docking. If a ship is hard docked at the time, the forces between a rotating station and a stationary space shuttle could rip both apart.

For a real emergency, where would escape vehicles be? You don't have time to suit up and space walk over to a co-orbiting vehicle. Escape "pods" in sections of the ring would be terminal. The first to leave would destroy the entire station, throwing the remainder off balance, ripping it apart.

Clearly there are lots of issues to be worked out. Bigelow could work on those problems now. But 30 years ago, there were many arguments about what was possible. I was in college then working for the military. One of my assignments was to provided documentation for visiting scientists discussing the space station (it was not international yet). I got to see documents and articles arguing all of these issues, and to listen to some of the debate. At another event I met Freeman Dyson and some other great minds of the century.

The ISS is what it is. We need to do more research. We need to understand the requirements of a space station, how to handle the environment, recycle water, etc,... first. We are taking baby steps. Dream away, but understand that taxpayers are paying the bills in every nation that is participating in ISS. The engineers owed it to everyone to deliver something that would work, and they did. They removed as many critical moving parts as possible.

Many of these problems could be worked out with a much larger station than we can reasonably consider now. Rotating the shuttle is not likely. The position of its docking apparatus makes it a no-go for rotating or being able to boost its orbit. A large station with its own maintenace crews could work. A gravity gradient tethered system might work better. Like a small space elevator in the sky. If you anchor your station to a large mass and let out a line a cetrtain distance, you begin to experience gravity. If you set up a docking station near the middle and fashion an elevator to go down or up, you will experience some fractional gravity as you descend to the station, or rise to it, depending on how long the tether is.. That might be a little easier way to get gravity that eliminates the rotation... Also, how much gravity do we need to maintain the health of astronauts on long missions? Is a third gravity required, 1/6, 1/16? We still don't know. Until we do, why build one if we can't design its specs?

 

[Gravity_Ray]

I too love the idea of a spinning station, however, do we really need another station? Right now, I would like to see NASA continuing to focus on a space ship. The most important issue facing us space advocates is money. To make money in space we need to get around in space first. Once we have that we can then think about semi-permanent space stations (spinning or no).

The ISS will answer most of the mundane questions regarding a low gravity environment and its affects on the human body that we need answered for now.

If for example you begin in-situ resource utilization of the Moon, Mars, or asteroids then a space station in one of the Lagrange points makes sense as a rally point or base. Or, if the space tourism industry takes off and they need some more space up there for rich folks to spend their money, then that will make sense as well.

For now lets focus on a space ship that will allow easy access to space not just LEO. Lets see if its even worth going to places like the Moon or Mars or the asteroids before we start building space stations. Remember if you are getting your resources in space rather than lugging them up the Earth gravity well, your space station will be that much cheaper.

 

[moonmadness]

lol

what space cadet hasn't designed their own station. if only in their head.

mine are always based on modularity design.

the first one I designed consisted of only two major parts.

Some oblong cylinder habitat modules and spherical connector units with six axis connection points(think the jack in the game of jacks).

I even used one of the first 3D modeling programs to flesh it out.

I was a little feaked out when I saw the first rendering of a Bigalow module because it looked almost exactly how I imagined my habitat modules so long ago.

My gravity station I called Big 8 because it was octagon shaped built out of tube sections that themselves were octagon shaped.

lol

 

[Gilmoy]

Afterall, we seem to do fine for 6 months at 0 g ...

Humans don't do "fine". Each 6-month stint on the ISS seriously drains astronauts' bone density and mass, by 14% average at the hip. That's even considering that ISS astronauts exercise two hours every day specifically to counteract it. It'd be even worse if they were in a cramped Orion phone booth the whole time. They have to recuperate for months on return. (Russians who flew long stints on Mir did experience even higher loss rates.)

In fact, bone loss is one of the reasons why we fly only six-month tours, and we limit astronauts to at most one long-term stay per 3+ years. It's one of several show-stopper reasons that prevent a Mars mission using current technology. (Lack of an effective radiation shield is the main one there.)

We do have some exercise machines in development that could generate substantial Gs in space. The Space Cycle sounds more fun than a barrel of monkeys: a spinning bar, powered by a bike on one side, with a cage counterbalance on the other. On Earth, it generates up to 7g for the guy in the cage! But the prototype is too large (in physical radius) and heavy. And there's the rather serious issue of whether the ISS is structurally ready for a 70 kg astronaut spinning at 7g in a small room. That's one mechanical failure away from throwing 70 kg of wet parts very hard against a non-reinforced wall. On Earth, we call that a trebuchet :shock:

 

[Jazman1985]

Gilmoy, my point wasn't that there is no appreciable decay in the human body at six months exposure to zero g, there certainly is, the point is that we can survive this time period. 6 months in an extreme environment is quite a long time without serious problems such as inability to walk or move. I imagine that in the future, foregoing Martian expeditions, we won't spend more than a year in low gravity, even with artificial gravity. Afterall, even professional astronauts will need a vacation... I would be very interested to see the effects that the mentioned gravity inducing bike would produce on the station, both psyhiological as well as structurally.

 

[spinor]

I have done a lot of reading in this area (artificial gravity using spinning spacecraft) and the fact is: we know very little about this area because
there is very little space mission flown for the purpose of researching in - artificial gravity using spinning spacecraft. For example we DO NOT
know very reliably the following:
1) the minimum rotation arm radius of the spacecraft to produce a comfortable habitat.
2) the maximum rate of rotation for the same reason - yes some says 4 rpm - but the
jury is still out on that
3) How long does it take for a healthy human to adapt to rotating habitat?

You just simply can not answer these questions with real degree of reliability with out flying real space missions with real rotating "tin can" or spacecrafts.
I don't know about you but I find it absolute amazing that for over 50 years of space history and there were maybe one (Russian) space mission
on rotating spacecraft for habitat purpose.

I also find it absolute crazy and even criminal that NASA would rather spend billions of tax dollars on "solving" the zero-gravity problem on the human body
than solving the engineering problem of artificial gravity via spinning spacecraft. Just imagine every time NASA builds some gadget for the ISS they have
to take into account zero G. Things like space toilet or urine recycling are example.

As Dr. Robert Zubrin pointed out - the zero G problems on human is an engineering problem. It is not a medical problem. Zubrin also site a very
interesting source to explain this idea. In what follow I am borrowing the same line of argument from him.

I would like to invite you to ask yourself these questions:
1) What do scuba divers do to help them breath under water? - They bring oxygen with them
The same with jet fighter pilot.
Now imagine if someone tell you that you can solve this problem by pouring a lot of money into
researching for a drug to reduce your oxygen requirement so you can live under water- you would
think that's a little nut don't you?

But we are facing the same problem with weightlessness on the human body! and the solution
is to "bring gravity with you". As Zubrin pointed out, It is infinitely more difficult to develop a drug that will combat the
zero-g effect than to solve the engineering problem of rotating spacecraft.

The human body is designed – over million of years by nature to live the a gravity environment.
You are not going to change that with any drug!

It is true that there are a many engineering problem associated with rotation spacecraft but all these
can be solved with some creativity or at the very least lived with. It may not be convenience but considering
how much money NASA have spent on "solving" the zero-g problem I can not imagine the solving
the engineering problems would be more expansive. The fact that it has been 50 years and we have not
come anywhere near a satisfactory medical solution for this problem should already tell you that something
is not right.

Also It is just my opinion but I do not believe that the maximum rotation rate for space habitat is 4 rpm.
I am willing to bet that when a large number of space experiments are carried out on this with a large
number of astronauts on varying length of stay you may find out the rotation rate can go up as high
as 12 rpm with habitat radius as low as 12 meters.

I am basing this on the losely notion that the effect of rotating space habitat may not be that much different
from what sailors experience at sea. I imagine that the effect of Corilois force and gravity gradient would
make you feel similar to sea sickness. Yet have you ever heard anyone said "you can not live at sea on
a boat below a certain size"? Of course not. On such boat you will feel seasick at first but after a certain
period most people will adapt. I will venture as far as to say that it is the same with rotating habitat.
You will undoubtedly experience motion sickness at first but perhaps after a few weeks who knows
many astronauts may adapt. We have to do the experiment to find out.

Finally imagine what if in the ancient day when the first wooden boat was invented and people would
abandon it because a few sailors experiences motion sickness?. The said men were meant to be at
sea? Aren't you glad that did not happen?

 

[Aerospace_Cadet]

The original design of the Space shuttle had larger external tanks that were going to be used as building blocks for a large wheel-like Station. Great idea making use of every part that you used all that energy to get to orbit. For some stupid reason (they quote monetary and political) they killed the plan and went with a smaller tank. Could you imagine the size of a station we would have today if we had over 125 external fuel tank sized building blocks in orbit? And now with the shuttle program winding down I'd say we missed a golden opportunity.

 

[RocketsRedGlare]

I think instead of an I.S.S. on steroids, we should build it large but, keep it as simple as possible and as cheap as possible! It should only be our indeavor alone. I doupt it will happen by us howevwer because we have an administration and congress that is bent on bankrupting our nation. In fact they don't even want America to be a nation at all! There is a reason that Europe after all these years has yet to put a man is space. They couldn't afford to, and that is where we are headed. So stop kidding that America has fute in space. we don't, soon we wont have the money to continue our programs. Our money will be worthless! We are so deap in debt we couldn't pay attention, we certainly won't be making a new space station with or without partners!

 

[xXTheOneRavenXx]

Giulio, I agree that we should have abandoned the old space station concept and worked on this kind of design since then. There are a couple of concepts we could utilize for modules that would not be affected by the artificial gravity. One would be a module on top of the outer ring. As the ring spins, the module remains stationary as it's attached to the outer ring via a magnetic track. It's not a new concept to have magnets keeping one body stationary while the other spins. To access these modules, a retractable access tunnel could be utilized. Another concept is to have the modules completely separate, but held close to the station again by magnets. Also, again magnets have been used before to keep two bodies at a given distance from each other, while still preventing them from drifting apart further. All that would be needed is a magnetic strip around the outer ring of the station, and magnetic panels on the module.

The cost factor always plays a roll in these projects, but you are absolutely correct in saying "who says this has to be done all at once".

 

[RPWalther]

1) Don't forget that one of the main purposes of a space station is doing research in weightlessness.
2) Moving around in such a station (from center to border or turning one's head while walking or climbing) or changing angular speed several times a day would probably cause endless space sickness!

But: For a spaceship to Mars consisting of two identical ships connected by a 200m long truss (with an elevator), 2 rotations per minute would generate Mars gravity (about g/2) and might very well help astronauts to stay healthy during their 2 year voyage! You could even do surgery! Furthermore you have a backup ship if one part is damaged.

RPWalther

 

[MrcACrl]

Coriolis effect- still unknown at this point. How will astronauts react? Why spend $50 Billion just to find it doesn't work? We can investigate this later.

I think this can be fixed by allowing transfer from the central to the outer ring o be slow. There are some issues we probably can't overcome, so some people will work in the micro-g section then transfer to the higher-g section as necessary (and vice versa).

Balance - If the mass in any place changes, by just a little, the whole station can begin to violently wobble. Just having astronauts walk around the station would not be tolerable without some sort of active balance system (read high maintenance, prone to failure, dangerous). Loading and unloading people and supplies would be very difficult.

This is just a matter of station keeping, isn't it? Boeing did it way back in the day with its spin stabilized satellite buses (and they kept the dish staionary in the centre while the rest of the sat spun away). Otherwise sats are actively stabilised so that they can point at specific places on the planet or stars light years away. One solution could be the use of balat, moving from one part to the other to balance things out.

Vibration - most of the arguments for building the station was as a research center, but the experiments require microgravity and extreme stability. A rotating station would not provide either. There would have to be a portion of the station that was not rotating, that would remain fixed in its orientation requiring motors (read high maintenance again).

Again look to the Boeing spin stabilized buses. They did it somehow and I've never heard ot a situation where the system locked up. I think some of their GOES weather SATS were/are spin stabilized.

Solar power - solar panels require a fixed platform facing the sun at all times. In order to get power, you need to mount a counter-rotating strut permanently fixed to the hub of the station.

Or you can cover the whole external structure with solar cells, like Boeing did.

Safety - all of the other issues aside, a rotating ring or wheel is inherently unsafe since the only point of egress is through the hub which also happens to be the only place to mount experiments, for the solar power panel struts, and a docking ring.
Docking - A hard dock in which two objects are physically connected so people can transfer easily between the two in a shirtsleeves environment is preferable to a soft dock

Docking would be difficult, I have to say. So the 'stationary'/counter rotating central bit is the best place for approach. That said, however, if the radius is big enough, it might not be impossible for an approaching craft to match the positive rotational speed of an outer dock, esp. if flexibility is built into it.

 

[MrcACrl]

Continued:

Weight - is another issue. A rotating structure would require much more strength in structural members which complicates design and launch requirements. Flexibility - as mass shifts in a wheel, the wheel gets out of shape requiring a lot of flexibility in joints between units and components.

Not impossible to engineer. Low statistical reliability but still possible. Just really expensive.

Attitude adjustment - how could the station's orbit be modified. Again, placing rockets and propellant around the central hub doesn't sound like a great idea to me. They would also need to be refueled. A visiting rocket would have to push ecxactly along the axis... Listen, this is getting too complicated.

What's so hard about just coming close enough and having spacewalkers or smaller, more maneuverable vehicles or Canadarms do the rest regarding attachement of umbilicals?

Finally, if the rotating docking hub seizes up, goodbye. No hard docking, maybe not even soft docking. If a ship is hard docked at the time, the forces between a rotating station and a stationary space shuttle could rip both apart.

Again, Boeing did it without probs and it's one of the first satellite buses they designed. The first thing that came to their minds... Not that difficult.

For a real emergency, where would escape vehicles be? You don't have time to suit up and space walk over to a co-orbiting vehicle. Escape "pods" in sections of the ring would be terminal. The first to leave would destroy the entire station, throwing the remainder off balance, ripping it apart.

Why??? You have an an airlock with the station on one side of the door and the escape pod on the other. Two stage escape process. Enter airlock, airlock closes behind you, enter pod, gone.

Clearly there are lots of issues to be worked out.

Clearly, but there are solutions though. Modularit might make it a lot cheaper than we think. Just design and develop 3 things essentially, central hub, trusses, and pods at the end of the truss. Can even put a flexible joining mechanism between the outter ring pods to make transfer from one to the other a breeze.

 

[bushwhacker]

one practical problem. if the center hub is not rotating, how would you dock there and transfer either to the spokes or outer ring?

 

[Exopaleon]

I think it's a waste of time and money, pouring big $$ into something that's just doing science. Take the money and start building shelters on the moon, so we can get going on some mining of the metals and H3. the odds of getting taken out in one of the shelters, or on the moon itself is extremly low, where as living in the space station, it's only a matter of time before it gets taken out by space junk. Setting up science stations on the moon would be the most logical next step. The space station is like a boat you sink money into, and never get your dollars worth. You can send a lot of shelters and mining equipment to the moon for the same dollars, and the reward would be a lot greater!

 

[habbuilder]

The BEST space station right now would be one ON the MOON or one able to get materials from the moon quickly and efficiently (using a mass driver?) so as to be able to process the materials and make more modules for the space station or more space stations (emphasis on the plural) and more space craft. I do not understand why we do not have a REAL shuttle capable of leaving the ISS and changing course to go to another orbiting object (say the hubble or a satellite in geosynchronous orbit) for repairs or modifications. Heck, we should even be able to recover dangerous space debris (garbage) and render it non-dangerous as well as recycle the materials. Its seems we could make the space program PAY for itself if we had these abilities. We need to quit screwing around with always taking things to space (expensive) and build it in space (eventually self-perpetuating). Why should this take so long? I thought the costliest part of space travel was the surface to LEO part??? Let's go NASA and Bigelow--go get those moon resources (As is stated in a recent news item the Japanese have discovered Uranium on the moon--just another reason to get there quickly and use the resources available!)

 

[MeteorWayne]

It's obvious you are young

After watching funding for space exploration for half a century the two things you can be assured of are:

Funding cannot be relied upon because it changes every year,

and

Funding will never be at a high enough level that I'd like my tax dollars to go for

Wayne

 

[Jazman1985]

Habbuilder, a space transport capable of repairing or modifying existing satellites or removing space garbage would be fantastic. Unfortunately the energy required to change the orbit of anything capable of collecting garbage would make this approach unrealistic. It would require vast amounts of fuel. Hence why the shuttle could not dock to the I.S.S. during it's hubble mission. Other than them being at different altitudes, their orbits are very different. Altitude can be made up easily, chance in velocity/direction, not so easily.

Any space station in orbit might serve as a first stop before heading to the moon or a last stop before reentering Earths atmosphere. Any new Space Station will not be there for "just" science, it will serve many functions. Most futuristic vehicles suited to enter LEO from Earth will most likely not be suited to space travel. A space station will make a good spot to switch rides. Even if a vehicle were to continue from Earth to the Moon, refueling with moon mined resources would be far cheaper than taking it all from Earth with you.

 

[Basketcase]

I personally think this is an awsome idea. Why dont we make LARGE rockets to be eccentually used as the segments. Make the rockets as complete as can be on the inside for all your lliveing quarters and such. Send them up unmaned at first or something if that is even possiable. To save on a return trip for the passengers cause if you use the rockets as segments what are they going to ride back into the atomoshere on. Make these rockets so the ends can connect to each other one way or another. I have no idea what the largest size rocket diameter or length would be, but if we can lanch a shuttle into space with sections for the ISS inside it then we should be able to make a rocket with as much or as little extras inside for it to get off the ground. Maybe have them Segmented or something so the propulsion system can breakaway when it reaches orbit, or even some how re-use that. I believe in re-useing as much as humanly possiable when it comes to large and costly endevours. Heck send up smaller rockets for the spokes. Put the stuff in a geo orbit and when you start asymbling it start reeling them in one by one. Turn it into a huge errector set. I think we can do a better job on building the pieces on the ground myself. But if you do that there is tons of weight invalved. So a large vehicle will be needed. This way it is the vehicle. No need for return trips or recovery and damn near rebuilding it lilke the current shuttles for the next trip. Fire one off and yell NEXT! But im no engineer. And what i propose may very well be impossiable. But that is what i think of when i hear lets build a better space station.

 

[pmn1]

The original design of the Space shuttle had larger external tanks that were going to be used as building blocks for a large wheel-like Station. Great idea making use of every part that you used all that energy to get to orbit. For some stupid reason (they quote monetary and political) they killed the plan and went with a smaller tank. Could you imagine the size of a station we would have today if we had over 125 external fuel tank sized building blocks in orbit? And now with the shuttle program winding down I'd say we missed a golden opportunity.

What was the extra size and weight involved in this proposal?