Large International Space Station rooms

Sorry if this is a really stupid question but why can’t huge rooms like in sci-fi films be built for the ISS?

No reason. Which sci-fi films in particular?

Star Wars, 2001, etc. I mean, aside from budgetary constraints, why not make the space station as large and luxurious as possible? From photos, it seems a bit cramped.

1- moving things up there is a bit expensive, sadly.

2- the more parts something has, the more risk involved. More room means more parts, even if it’s just structural supports and wall panels.

3- most of the parts that are shipped up are either part of a rocket or carried up in the shuttle cargo enclosure.

But the real reason is cost. Why have a huge open room, which you have to pay to fill with air and life support, when a small closet will do the same things.

Eventually, you will see more spacious and luxurious stations and habitats. Of course, this will only happen when private industry takes over, but still…

I would think collapsible structures you could blow up like blimps would be practical for the space station. During launch they would weigh very little and you could have very large volumes from such structures.

Mayhaps. But stability and such becomes an issue there.

Really, it all comes down to cost. As a wise man once said:

**“If a question starts with ‘why’ or ‘how come…’ the answer is always money.” **

AFAIK the walls of the space station are pretty thick, this being necessary to resist the bombardment of tiny, but fast moving particles.

Inflating structures have been tried in space with some success - reflecting parabolic shapes for example. Presumably, only very low gas pressures are necessary.

A habitable, inflatable structure might be possible, but would be rather dangeous as it would be very likely to be punctured.

Perhaps some sort of self repairing material could be developed, rather like fighter aircraft fuel tanks. Perhaps not safe enough for habitation, but good enough to grow some fresh food on a trip to Mars.

Until a tiny little asteroid hits you moving at a few tens of thousands of miles per hour and pokes a hole in your room and you jet around space just like what happens after you let go of an untied party balloon.

Whatever you inflate it with, you’d have to carry that up.

NASA has a working prototype of an inflatable structure. It has many layers of fabric to avoid punctures getting all the way through. Unfortunately, this also makes it pretty heavy, so the cost thing is still a pretty significant barrier to making really big rooms.

From 1999, and they say it will go up in 2004. I imagine that date will be moved back considerably.

In general, pressurized structures get weaker when you make them larger. It’s the curvature of the wall/skin which supports the structure, so the smaller the curvature, the weaker the wall. It’s easy to make a 1-ft diameter ball that withstands 1 atmosphere pressure, but a 100-ft diameter space station module needs a much stronger wall. (100 times stronger, I think.)

It’s the same reason why racing bicycles have such narrow tires. You need high pressure to reduce friction, and to achieve a high pressure you need to make them narrow. You just can’t get a 2-inch wide 145psi tire, but 23mm-wide 145psi tires are common. (Another reason is aerodynamics, of course.) You’ll also notice that high-pressure gas tanks are usually very narrow cylinders.

There are other problems too. I think Skylab had the largest open space of any spacecraft to date, and astronauts often actually had problems of getting stuck in the middle of the room, out of reach of the walls. Granted, this isn’t exactly a life-threatening problem, but it did cause a lot of trouble from what I hear.

But mainly, there’s just no point in doing it…

Yea, I was gonna say, in sci-fi you always have lovely artificial gravity… currently, you kinda need it to be small so you can get around quickly and access everything easily.

It isn’t a resort, it is a scientific station, for the most part. They have instrumentation everywhere, everything is strapped down, and they need to be able to access it. The most logical form is a smallish tube. It withstands pressure well, makes getting around easy, is simple to transport, easier to make modular, takes less gas to fill and recycle, and is generally a better plan.

It seems that bubbles have been considered as an emergency rescue measure. See here.

Aside from highly visible budgetary constraints, no reason.