Is such a thing even possible?

In one respect it's a little less incredible than it looks

It's a 400 ton payload. A Saturn V could carry a 140 ton payload and a space shuttle could get up to 110.

It's not an awe inspiring order of magnitude heavier, it's meant to be big AND light.

The ITS second stage is launched un fueled, it is put into a parking orbit by the first stage candlestick booster, then re fueled by use of fueling vehicles in orbit.

Yeah, it's mostly empty right?

They could feasibly send it off empty, and then use smaller vessels to fill it up with passengers and supplies afterwards.

Plan is to send it up crewed, fuel it in orbit with a few equally as massive second stages, then send it on its way.

Yeah I know, but no plan survives reality. I'm just concluding that they could feasibly cut a bit of weight from the initial plan still.

The Space Shuttle had a maximum payload capacity of 32 tons, to LEO, although it never exceeded 25 tons, it had no ability leave LEO.

The Saturn V could carry 155 tons to LEO and 53.5 tons out of Earth orbit

Had Von Braun's Saturn V-23(L) ever been built it would have been capable of 290 tons to LEO and 110 tons out of Earth orbit

You left out the 5 inch guns and nuclear missiles.

NUKE THE COMMIES

FUCK EM ALL

Anything's a dildo if you're brave enough.

>assuming we could gather all the necessary materials.
Well there's the rub, isn't it? How do you bootstrap a space mining industry without launching a shitload of stuff up there?

>It should be much more efficient to build ships that are not designed to land at all.
But how do you even get up there, then? How do you get down?

You need a good reusable rocket like this. A big one is more efficient.

>The Space Shuttle had a maximum payload capacity of 32 tons, to LEO, although it never exceeded 25 tons
Keep in mind the space shuttle was a big fucking payload itself

>There are plans for superconducting magnetic guns that can fire stuff into space though, which would make transporting the raw materials for building the ship into space much cheaper

Reminds me of Ace Combat 5, they used a spacegun to build the massive spaceship that you later shoot down at the end of the campaign.

>There are plans for superconducting magnetic guns that can fire stuff into space though
Is there a source for that?

>What are the technological challenges for building these spaceships in orbit, assuming we could gather all the necessary materials.

NASA or others would have to build tugs then git gud at using them.

>It should be much more efficient to build ships that are not designed to land at all.

Yes but presently there is no demand for such large ships.

For what it's worth a core part of Constellation (and really any future Mars shot) was for a transfer vehicle to be assembled in orbit then fueled by a separate craft. Likewise NASA also looked at an orbital Mars fuel depot, which would be supplied by a burner rocket. So the idea isn't dead, it just hasn't been used yet.

nextbigfuture.com/2008/02/magnetic-catapult-feasible-advanced.html
It's a blog so not the best source, but it seems like a nice summary of the paper. Here's the paper:
rangevoting.org/WarrenSmithPages/homepage/launcher.ps

We need to start somewhere.

Once access to space becomes cheaper we're sure to see that happen.

Potentially we could hollow out asteroids, put a spinning tube in (for gravity) and put some thrusters on it. It would provide good protection from radiation and impacts.

The problem is that it's impossible because of the atmosphere. The exit would need to be to high up where the atmosphere is thin enough.

It would work on the moon though. I can see a lot of heavy industry move to the moon. It's actually a lot easier to escape the moon than to land on it.

A fleet of robot crafts with ion thrusters would capture asteriods and put them into orbit around the moon. Where they would later be processed and turned into building materials.

Atmosphere isn't as much of a problem as you think it is, although the idea definitely requires more investigation.

It's meme shit
Nothing will survive hitting the atmosphere from a tube at 12 km/s
Maybe in 50+ years when magnetic rail guns are proven tech, then you could build a big one for launching payloads to orbit

>initial speed 20-25 km/s
k
more meme shit

>nothing survives hitting the atmosphere at those speeds because I feel like it
>maybe in 50+ years it will become feasible, even though I've just said it's impossible
No-one is talking about the near future you dumbass, and it's not a fucking raligun.

Are you retarded? The paper written literally by a mathematician details just how the projectile should be accelerated to those speeds.

>literally by a mathematician
So a totally-unqualified person in engineering?

and that mathematician literally has no first hand experience with this shit and is simply dabbling in the theory and is less concerned with the reality

tanks, pressure vessel, all out of composites? hmm what could possibly go wrong

The vision O'Neil had in the high Frontier is that the guns would shoot mined materials from the moon to Lagrange points for processing/construction, which does not involve the atmosphere.

In the book he says that he and a few of his other physicist buddies made a working model but once funding dried up they couldn't develop it any more.