Apart from its assembly, which was a great achievement, can anyone cite genuine science that the ISS has accomplished -- that could not have been done otherwise?

learning to build and sustain large structures on orbit is critical to our next steps. That's what ISS was always about.

It's a worthwhile question, despite already being asked, repeatedly, from before the station was even started. There's a long list of experiments which have been run, but I'm trying a different tack, listing just two things.

"Apart from its assembly, which was a great achievement . . ." Yes. Think about the mid-term future seen in hard, i.e. "realistic" science fiction. Whether it's ice haulers from Saturn, moon miners going after aluminum, with oxygen as a by product, or whatever - how do we get to this world, uh, this solar system?

Now, there's a debate on how big a launch vehicle should be, and I'll admit I held the opinion that SLS was too big, until I saw Starship. Still, the point is, there will be some limit, some day. What then? To put it crudely, we gotta build stuff, lots of stuff. Assembly is part of manufacturing, so in that sense, building the ISS and previous stations count as beginning steps in space manufacturing. Start small, then move on. Next, Star Dock.

The second big thing from ISS is that people learned to live and work in space in order to learn how to live and work in space. Period. There is no way to overstate the importance of this achievement. Again, small steps first.

These two are the "what" of the question, what answers did we get. Now, could the process have been managed in a faster or more cost-effective manner? Probably, though that's a separate discussion.

I think these two achievements qualify as goals met. That's not to say I'd let NASA off the hook completely. In the decades long scheme of things, the agency has had 65 years for serious answers to the gravity prescription, and has done basically doodly. Short recap: Gravity Rx questions says, we do OK at 1 g, and there are significant issues with zero g, but what about long term living at 1/6th g, or 1/3? We have nothing, nada to show for the decades gone by. I don't consider possibly more efficient fiber optics cable a reasonable substitute, cool as the experiment was. Oh, sorry for the rant. Talk about a separate discussion.

So in my humble view, the purpose of NASA is to get us moving to Moon, Mars, solar system. The rest is interesting, but not of prime importance. I realize this is not the official, or the majority, view, but that's life. :)

I think NASA could probably have done Alpha Magnetic Spectrometer as a free flyer, but not for remotely as long.

I think AMS has generated more papers than anything else on ISS.

All the various microgravity experiments that have been done...some could not have been done remotely. How much value those have is open to debate.

AMS has generated more papers because it involves by far the largest numbers of scientists from by far the largest consortium of nations, far larger than ISS itself. The real question is whether it has made worthwhile discoveries?

I suppose we would have to define "worthwhile"!

Has it made discoveries? I am waiting to see a Nobel Prize.

https://www.nasa.gov/missio...

No doubt there is a big catalog of experiments done on ISS. NASA and ISS/ISS Science has a real rah-rah cheerleading section, but reality is that a lot of those experiments are the same experiments flown previously on Shuttle, Spacelab, Mir, and many are experiments repeated many times over many years on ISS. This is more so the US science program.

Other countries are doing more and more innovative and original research involving new ideas.

In a 'cost-saving' move US ISS management cut their support for US ISS science development; they earned a lot of ill will from academics and researchers when they eliminated the budget overnight without any kind of announcement or discussion. They decided that other "science agencies" (NIH, USGS,...) should be responsible for research on ISS. NASA's human space flight managers turned their backs on science in human space flight. The rationale was that the ISS contractors needed more money. Another stupid move by some really poor ISS management.

ISS has done some work in cataloging effects of zero G on humans. Mainly that shows that humans can survive in zero G. Not sure how important that is. For most planetary missions we need to show how people will do in partial G, not zero G. One of the main research programs that was supposed to have been pursued was experimenting with partial G levels. There was a specialized module for this purpose built by the Japanese and ready to fly. ISS management in a shortsighted cost savings measure cancelled that module's launch and that program was cancelled and nothing has been done. The module sits rotting outside at the entrance gate of one of the Japanese Space Agency centers. Really another stupid move by shortsighted ISS managers.

So the question is whether any of the science done is significant or important. Personally I've not heard of anything.

In terms of other sorts of research; not science. A lot could be done with ISS to show how to operate a planetary space vehicle or habitat. Developing AI systems, permitting and demonstrating independence of the crew. That is important research that needs to be done for the Moon and for Mars. NASA and ISS managers have gone the other direction, more fully integrating mission control into the operation of ISS. Ground controllers now manage the operations of systems on ISS; ground controllers now drive the robotics; there are very few operations actually executed on board by the crew. This is because the mission control operators felt they would be left behind if more independence of the on-board crew was permitted. Still more shortsightedness by NASA's ISS managers for poor and selfish reasons.

Seems a bit disingenuous to dismiss the entire catalog of experiments out of hand as "there's nothing I've heard of." I'm not sure what qualifies as important for you, but clearly someone saw merit in them, otherwise they would not have been pursued.

That said, I agree with you about the Japanese module that was supposed to study partial gravity.

Some of us actually have expertise on the program; we've been researchers, integrators, operators. We've sought material to serve as the source for writing and as the basis for new experiments.

Yeah, I'm just a guy sitting here on the sidelines watching the game. That said, I'd like to believe that some level of useful science has been conducted on the ISS; that there is some return on investment.

In a 'cost-saving' move US ISS management cut their support for US ISS science development; they earned a lot of ill will from academics and researchers when they eliminated the budget overnight without any kind of announcement or discussion.

Alas, science has always been a secondary (or worse) consideration for NASA's human spaceflight program, right from the very beginning.

There was actually quite a bit of attemtion paid by NASA managememt, recognized heros like Seamans, George Low, Bob Gilruth, towards earning the support of scientists amd academics most notably on Skylab, but on Apollo and early Shuttle too. At one time USGS wanted to control.science on Apollo. They werent allowed; that was all run by Houston. More recemt NASA and Houston managers forgot their origins and training and felt they would get more support by sending their scarce dollars to Boeing rather than universities. Boeing and other contractors took NASA for a ride. I think it earned some of the managers lucrative retirement homes.

Boeing and other contractors took NASA for a ride. I think it earned some of the managers lucrative retirement homes.

I hope they got a great view out of 'em.

The truss should be saved at least.

Unusable without modules.

We never seem to admit to ourselves that ISS is a prototype space station. We had never built one before and didn't know how to design a productive space station when we built it. It was our best guess at the time. It's main flaws were too few crew members and infrequent cargo trips up and especially down. The additional crew enabled by crew Dragon has helped, but the the new commercial space station designs will be much better due to lessons learned from ISS.

'We'.
Russians had built a half dozen. And 4 somewhat different varieties: the original Salyut amalgamated from various pieces, the later Salyuts and Almaz, and Mir.
US had designed and built 2: MOL and Skylab. MOL was only flown unmanned in prototype form.

Run an internet search for Space Station Research Explorer on NASA. It lists all of the research experiments that have been done on the ISS.

I would say the assembly was not such a "great achievement" considering if von Braun had been give a few more million dollars to make Skylab a wet workshop, instead of the lesser dry one sent up, we would have launched a larger space station than the ISS in one afternoon on one rocket instead of.....

However, the data on dosing and debilitation was important and this tells us a Near Sea Level Radiation 1 Gravity (NSLR1G) environment is what human beings require to function for long duration missions without career-ending radiation dosing or permanent damage from debilitation.

That data is in and we can now move on.

You ought to study some history. The wet workshop was unworkable, decided so by von Braun himself. And you should study some physiology. No such finding of the need for 1G. The research is wide open on that. And as far as radiation attenuation, shielding needs to be built into the spacecraft. So far you are striking 0 for 3.

Also true there is no need for sea level or near seal level irradiation levels. Anyplace now known on Earth where people naturally live untroubled much by radiation is obviously fine from a physiologic standpoint.

Actually radiation levels in high flying aircraft and in higher elevations are somewhat higher than ground level. I don't think pilots, stewardesses or people dwelling at high altitudes are too concerned about their higher doses.

That's our Gary.

His idea of how space exploration should be pursued is stuck in the sci-fi ideals of 1960s scifi authors like Heinlein, and anything that uses technology developed after about 1968 is just pure evil.

Go ahead and cite von Braun stating the wet workshop was "unworkable." I want to see that...really.

And because there is "no such finding of the need for 1G" then why do astronauts suffer debilitation, including permanent damage?

And as far as shielding being "built into the spacecraft", the world's leading authority on space radiation, who I often cite, has explained that just creates more secondary radiation. You obviously don't understand why astronauts would retreat into a "storm shelter" and as soon as possible leave it.

So far it is you O for 3...with a dunce cap.

So far you are lying like a fanboy. They lie like the rest of us breathe.

That's true. The two-stage Saturn V sent both the Skylab and the S-II second stage to the final orbit (425 km altitude, 50 degrees inclination, circular). So, the launch vehicle had plenty of payload capability to put a wet workshop version of Skylab into orbit that day (14May1973).

Unfortunately, only a few Saturn IB launch vehicles and Apollo spacecraft were left in NASA's inventory when Skylab was launched. So, there was no way to send large amounts of cargo and replacement crew to Skylab to continue operation longer than about 10 months.

To send cargo to Skylab, a new uncrewed cargo spacecraft would be needed, probably launched on a Titan II, like the Gemini spacecraft were. And to send crew there, a new spacecraft with a minimum of three seats would have to be developed.

Then there would be the problem of autonomous rendezvous and docking of an uncrewed cargo vehicle with Skylab. The Soviet Union had such capability but not NASA.

By that time (1973) all of NASA's human spaceflight budget was being spent on the Space Shuttle. It would require 26 years (1973-1999) before NASA launched the next space station, ISS.

Side note: My lab spent nearly three years (1967-69) doing development and testing work for Skylab.

If von Braun had been fullly funded for a wet workshop project then they may have funded more crew taxis. It is not like it was impossible.

The salient feature of the era was canceling the Saturn V instead of continuing production. To paraphrase LBJ; "they pissed away a great capability."

And it is not like VTVL was an unknown possibility after decades of sci-fi movies and Phil Bono's concepts. The Saturn V could have been made reusable, stage by stage, piece by piece. That would have been the logical progression, instead of solid fuel boosters and wings and landing gear in a vacuum. The Shuttle was a complete wrong turn.

There is not a market that will pay for another space station; the current market cannot even afford to sustain the existing ISS. However, the only reason why there is planning only towards 2030 is because the US government plans in 6 year cycles and so 2030 is as far as they are planning right now. But as Mulholland said, the ISS continues to work as planned. It has been well maintained. There are no major systems failures ongoing or anticipated. The entire ISS is modular in its design approach so if there were issues, any system or element could be replaced. So there is no reason to talk of disposing ISS. It is a viable facility in Earth orbit.

The best approach would be for NASA to hire on contractors to operate and sustain ISS, reducing manpower and costs to the greatest extent possible. NASA would continue as an anchor tenant offering limited research capacity to government, academic and industry interests, but over time relinquishing a lot of that capacity for the contractors to sell and develop a market.

NASA and Congress should be wary of that government-industrial complex which will always opt to throw away the old system in favor of building [at US taxpayer expense] a new replacement system.
There is zero reason to be talking about disposing of ISS, not for many years, perhaps decades.

I hope there's a market for privately-run space stations in LEO. I don't think it can be done if the costs of deployment and sustainment are the same as the ISS, but if private stations are much cheaper, it seems to me there would probably be a small but active market in granting access to space for corporate and academic research and science, tourism, and opening up access to space to nations that can't field their own manned spaceflight programs.

If the cost comes way way down then there will be many more uses and users. Some might prove worthwhile.

The costs are in the facility, its operations, and the transportation to get there and back.

Musk's Space X is driving transportation costs down.

Facility costs need be little higher than for building an aircraft fuselage.

Operations costs need to be brought way down. That can be done if the station and crew become somewhat autonomous. We have to leave the enormous and costly mission control infrastructure behind. That was needed in the days before computers. That day was over many years ago.

Certainly there should be no talk of replacing ISS at NASA expense. NASA has learned how to develop and emplace the technology, so using what NASA has learned, see if NIH, USGS or other 'science' parts of governmemt are willing to support (fund) a new space station. If the answer is 'yes' then NASA succeeded. If the answer is 'no', then more needs to be done on ISS.

Zero reason? Really? It is a 4 billion dollar a year bunch of tin cans going around the Earth 250 miles up accomplishing zero. Automated labs can do far more research at a fraction of the cost. It was time to splash it in 2016 and move on Beyond Earth Orbit.

Those making money off it do not want to see it go of course.
That is the "taxpayer expense."

The same company the fanboys endlessly scream bloody murder about because of the SLS....but because the ISS is a NewSpace cash cow it is fine.

It is a scam.

We are in the space environment to stay. That includes Earth orbit as well as beyond Earth orbit. It includes people as well as automated elements. ISS has proven a great workshop for working these elements together.

The $4 billion a year is a man-made construct. That is the amount it takes to maintain a large government and contractor workforce; it has little to do with actual costs of operation which could be far smaller. If anyone thinks a new space station will be less expensive, or less expensive to maintain, that is a fallacy.

Look at what happened with Shuttle-a great example. We couldn't afford to operate a Shuttle system which was launching 4-6 times a year for a cost of $3-4 billion, a $$billion a launch we were told. The Associate Administrator at NASA responsible for space flight said "we need that money to develop the new exploration systems". After more than a decade, after having developed essentially zero new technology at a cost of tens of billions $$, now we are operating a Shuttle-derived SLS at a cost of $4 billion a year, which will launch every other year. So it is now costing us $4 billion a launch (or maybe it is $8 billion a launch). That is not progress!

" If anyone thinks a new space station will be less expensive, or less expensive to maintain, that is a fallacy."

It's hard to look at a station like Starlab or even Axiom and think that they are going to cost as much to operate as the ISS does.

Why is a new facility required in order to lower operations costs?

Because ISS is constructed so as to be extremely expensive to maintain.

I disagree. It is operated in such a way to make it expensive to operate. The systems are state of the art and could be operated and maintained very differently.

I'm unclear why you think so?

It's generation-old tech, and it's ageing. 85-90% of crew time (assuming a max crew of 7) is spent just keeping it running. If an ammonia tank goes out, that's an EVA.

NASA is not exactly adept at "cost effectiveness," but it is not like they haven't looked for ways to reduce costs, or had commercial operators study the problem.

At some point, it has to be abandoned, and "sometime" looks to be in the next 5 to 10 years. Any station that comes after it will have to be operated by someone other than NASA, and it's going to have be designed from the ground up to require as little maintenance as possible. It's going to have be designed from the ground up to require no EVAs to assemble.

But that seems to be exactly what the commercial LEO companies who are in development seem to have in mind.

Because once a system hits its projected End of Life it becomes increasingly more expensive to keep it up and running, and the longer past EOL you go, the more expensive it becomes.

If anyone thinks a new space station will be less expensive, or less expensive to maintain, that is a fallacy.

Why would a new, privately run space station have to cost as much as the ISS? Surely there are many technological developments and lessons learned from the ISS that can be leveraged to drive down cost for next generation stations.

Absolutely, that's the key, to clarify that we're talking about taking the technical lessons from ISS and then the funding from the private sector. Then, any next-gen station is actually a "product" the market will want to buy.

Applying "lessons" from one program to another in the US NASA program has not worked. Each program promotes their own people, often who have zero experience in the appropriate subject from prior programs. In their chauvinism they always say they want to do a "better job" than their predecessors from the earlier programs. But they usually have no idea what went on in earlier programs. They have zero knowledge of earlier lessons learned and no interest in applying them.

For payloads and experiments, NASA went through a series of lessons, starting with Apollo, trying to improve with Skylab; Shuttle, with new people got off to a rocky start integrating payloads. Eventually they improved on the process. Spacelab, meanwhile, used antiquated technology and a bureaucratic integration process. The commercial Spacehab project developed better processes because they were not working on a cost plus contract. The more payloads they could fly the more money they could make. Many of these expedited processes and documents were applied on Mir because the people who had done Spacehab were in charge of the same processes for Mir.

In the meantime the Spacelab people moved into ISS and for the first 15 years ISS processes were as bad or worse than Spacelab had been. All of the expedited and simplified processes developed in Shuttle, Spacehab and Mir were lost. After 15 years ISS recognized their processes were killing their science program and so they decided they were going to improve things; it was the "RISE" initiative; but by that time they had no one that had any idea how to do the job. So it has languished.

ISS is a fine facility.
It should be after the years spent in design and development.
It is well equipped. It is very capable.
If the need is to get operations costs reduced, why throw the facility away?

ISS is state of the art...for 1997. Like nearly any other form of technology, space stations can be improved through iterative development.

ISS is totally modular. If you want new computers, they and their LANs can easily be replaced. They've been replaced multiple times. ECLS has undergone iterative improvements as have several other systems. There is no reason why major assemblies or even modules cannot be replaced. The expense was in building up and assembling the infrastructure. There is no reason to eliminate it now and replace it with something less capable. If we want lowered operations costs, that is a separate discussion.

No, it is not modular. The Z1 truss or lab module can not be disconnected. The vehicle can not operate without neither of them

"Bad grammar makes me [sic]."

Heh.

By that standard, a Ford Model T is totally modular as well, and plenty of people managed to modify Model Ts into high performance hotrods, but those still can't hold a candle to a Tesla Model S Plaid Edition.

I'm not generally in favor of splashing the ISS, but I have seen plenty of government systems that were hog tied because they were reliant on technology that was far beyond End of Life, and held together by the technology equivalent of baling wire and bubblegum.