It's not a fair comparison: You're comparing how much it costs to move 1kg with a Mini Cooper vs moving 1kg with an 18 Wheeler.
I'm not disagreeing with the Falcon 9 being incredibly cheap, and the SpaceShuttle being outrageously expensive - I agree with both statements. I just think the direct price comparison is bad.
> You're comparing how much it costs to move 1kg with a Mini Cooper vs moving 1kg with an 18 Wheeler
Most of the Shuttle’s payloads were aggregates of smaller payloads. For big stuff, sure, the Shuttle retains its mantle. But it simply wasn’t launching that much big stuff.
Skylab was 77 tons and launched on a single Saturn V. The ISS is 420 tons and took, among other things, 27 space shuttle launches to put together[1].
So to a first approximation the ISS could have been over 2000 tons if NASA had just stuck with and scaled up the Saturn V architecture, which history has shown was both more capable and cheaper.
So no, the Shuttle isn't what allowed us to construct the ISS. Except in the narrow sense that the better launch vehicle had been cancelled, so it was the only project left to do the job.
I don’t think you understand what the Shuttle did for the ISS it’s not about it being a launch platform but about it being a huge EVA and construction platform from which in orbit construction operations could be run.
We have no way to do any major service to the ISS now without the shuttle and the ISS retrofit was the main reason for the deferral in the Shuttles retirement.
As the Soviet/Russian Mir showed you don't need some shuttle-like vehicle to construct such a station. Mir was 130 tons, and almost exclusively launched by Proton-K's, which have a 20 ton mass to LEO.
By comparison the Saturn V has a 140 ton mass to LEO, 7x what the Proton-K could carry, and more importantly could have carried modules double the diameter of what the shuttle could put into LEO.
The unique selling point of the shuttle was the ability to return payloads from orbit to the ground for servicing, but as it turns out that was much more expensive than having a cheaper launcher and just launching another module.
Let's not draw the wrong conclusions from history. The shuttle was a failed launch system by any reasonable criteria. History has shown that plain old boring boosters were the right choice. The Soviets/Russians have been able to launch things to the ISS after the US lost its wings.
The only reason we have "no way to do any major service to the ISS" is not because the shuttle was so great, but because it was a dead end. The US has had to play catch-up with the COTS program with SpaceX et al.
No if anything MIR shows us is just how much we needed the shuttle.
MIR wasn’t only 4 times smaller than the ISS in terms of tonnage but it’s design was the same as the Salyut and Skylab the ISS was the first thing we can say we actually constructed in orbit.
There's nothing indispensable in the Shuttle design. All of the ISS construction operations could have been done with a (possibly specialized) traditional spacecraft. Non-autonomous USOS-style module delivery and berthing, truss mounting, EVAs etc. Shuttle has been used in ISS construction just because it was available.
The only thing that could have been somewhat complicated without Shuttle capabilities was returning the Mir solar panels, for detailed analysis of their faster-than-expected degradation.
There’s no fundamental reason ISS modules couldn’t autonomously dock with each other. The main reason it wasn’t entirely built that way (though some sections definitely were) is because of the desire to create a PR justification for the Shuttle. In fact, modules have been added to the station since the Shuttle went out of service, and will continue to be added. Anything that couldn’t connect that way you could install onsite using EVA by ISS crew and the ISS Canadarm, which is a level of capability you could easily reach by launching autonomous self-powered modules.
Proton-K could launch 80% the weight of the Shuttle. Note that only 11 Shuttle launches were over 20,000 kg, which is well within the Proton-K weight envelope. (Not to mention the Titan IV.)
I welcome the change in comparison, Shuttle vs. Proton-K makes much more sense. But back to your point that's being discussed: How many Falcon9 launches would it take to lift a similar share of the ISS? How much would that cost?
> How many Falcon9 launches would it take to lift a similar share of the ISS? How much would that cost?
Most ISS components were less than the Falcon 9's capacity. Given Falcon 9 launches payloads an order of magnitude cheaper (cost per kg) than the Shuttle did, cost savings would almost certainly be realized. The remaining payloads would be more expensive to launch on other platforms, but that extra cost for a few projects is outweighed by the savings across the bulk of what the Shuttle did.
For heavy-lift launches, Titan IV and Proton beat it. For manned launches, Soyuz beat it. Today, Falcon 9 and Falcon Heavy are better options, though they are built (in part) on the lessons of the Shuttle.
> Most ISS components were less than the Falcon 9's capacity.
I want to see the attempt of building the ISS with a Falcon 9. Some assembly launches would be within lift capacity (especially on the expendable configuration). Some payloads would actually fit in the fairing. But when you have it in orbit - what then? The Space Shuttle not only lifted the modules into space, it berthed them to the station, and carried the crew together with the payload to execute the assembly operations and be able to react in time.
As much as I agree that the Space Shuttle was way too expensive, it was irreplaceable for building the ISS, and had it existed back then, the Falcon 9 wouldn't have changed that.
If it was irreplaceable how did the Soviet Union / Russia build Mir? A space station 1/3 the weight of the ISS and incrementally assembled in space from multiple modules.
They built it with a lot of drawbacks: Small modules, complex assembly, requiring modules to have their own propulsion systems, etc.
Plus, since this seems to get forgotten a lot, size matters. I find the best size comparison between the ISS and MIR is with the Space Shuttle attached: ISS [1] vs Mir [2].
That's if anything an argument for a Saturn V carrying some platform that would look like the flight deck / cargo bay / Canadarm part of the Space Shuttle to orbit to help with in-orbit assembly.
Sure, you might need some such platform to construct something in orbit. That's basically a space forklift with thrusters.
It isn't an argument for Space Shuttle system as a whole, i.e. propulsion system, heat shield, solid rocket boosters & external tank, being needed.
For what it cost to launch the shuttle such a platform could have been entirely expendable with astronauts returning in capsules, and they'd still have saved money, and been able to take up 3-4x the amount of cargo up on each trip.
I'm not disagreeing with the Falcon 9 being incredibly cheap, and the SpaceShuttle being outrageously expensive - I agree with both statements. I just think the direct price comparison is bad.