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> NASA announced SpaceX has been selected to develop and [emphasis mine] deliver the U.S. Deorbit Vehicle that will provide the capability to deorbit the space station and ensure avoidance of risk to populated areas.

> The single-award contract has a total potential value of $843 million. The launch service for the U.S. Deorbit Vehicle will be a future procurement.

So...with $843M, what could SpaceX come up with? In Gwynne's shoes, I'd be looking to develop a vehicle with far wider application than a 1-off LEO deorbit burn.

And, given the inability of most of SpaceX's competition to reliably delivery anything to orbit, I suspect that NASA has similar hopes.

Such a shame. Can’t we dismantle it and bring the pieces down in Starship flights? The American parts would look great at the Udvar Hazi. As for others, each one can be delivered to its country of origin.

I’m assuming anything that did fit in a shuttle could fit inside a Starship.

Not sure Russians would like that though. I’m betting they would prefer their pieces deorbited.

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I'm not sure how much they can carry on re-entry. More heating etc., and more weight when doing the landing.
They’re going to enter mars atmosphere with a full payload at a faster speed so I think it could handle it.
Mars has less gravity and less atmosphere, so its not a comparable situation.
thats the intention, its hardly a proven.
Mars has less than 1% the atmosphere of earth. That makes it easier in some ways and more difficult in others. I don't think you can really judge the performance when landing on Earth by looking at the performance when landing on Mars.
Also they’d need more fuel for the de-orbit burn.
Its going to be Starship again surely, with the right docking stuff to attach to the ISS.

Or a modified Dragon?

Modified Dragon seems like the simplest option. Dock and then burn retrogade while attached. Probably not nearly that simple in reality though.
You don't need a lot, just something lined up on the correct axis with enough engines and fuel to slow the station down enough to fall out of orbit. The station has its own propulsion (on Zvezda & Zarya, I believe) even with most of its station keeping being down by Progress etc. There's no reason they couldn't loft something with an F9 (23t to LEO) or maybe FH (64t to LEO). With the fact that it's going to burn up in atmo anyways, you can strip a lot out of the existing cargo dragon.

You can slowly deorbit anything with enough time/fuel. It's just a matter of how fast NASA wants to make it happen to assure it lands in a specific spot and doesn't breakup too much while still in "orbit" (see also: atmo + solar panels).

According to https://forum.nasaspaceflight.com/index.php?action=dlattach;... (PDF)

> The deorbit vehicle will need to provide at least 3236 N thrust to hit the target delta-v within a 60-minute time period.

Each Draco on Dragon can deliver 400N, there are 16, that's 6400N. So unless I've missed some math somewhere, a Dragon could do the deorbit. Ignoring the fact that they probably haven't burned those engines for an hour. Also fuel required for that manuver.

>Also fuel required for that manuver.

Ah yes, that pesky detail of the rocket equation.

Super complex, but could the fuel & thrusters be staged -- waiting in lower orbits -- so you don't have the mass of all of them at once?
It could, but it's never been done before. SpaceX just tested some fuel transfer in zero-G for the first time with their second Starship test.
Couldn’t we put it in a super long orbit that means it will revisit earth in a million years or something? Might be a nice surprise for whoever is around at that point.
It's considered unwise to leave uncontrolled vehicles in orbit, as they may hit other uncontrolled vehicles (or natural objects) and create debris.
An orbit like parent post is talking about is barely an orbit and more like an escape trajectory that just barely fails to escape.
Would need lot of extra fuel to raise altitude for an escape trajectory. Fuel either brought up the gravity well at launch or later refueled in orbit. Of course not all satellites are designed to allow in-orbit refueling. Maybe an reusable orbital tug might be something that someone will come up with.
It doesn't have to be one vehicle. You can launch 10 falcon 9s (perhaps even using the same booster) and have them take turns pushing.
Do you realize that 10 F9 flights means 10 new second stages and on those second stage someting has to sit and that something whatever that is - is completely dwarfed by ISS and it would have to be a new dedicated vehicle consiting of mostly fuel just to deorbit the sucker in one go.

Original plain AFAIR was to use several Progress vehicles.

And going to graveyard orbit with something like ISS is not just a few whole times more difficult but at least an order of magnitude more.

The ISS weighs 450 tonnes.

Ten Falcon 9s (with 8 tonnes to GEO each, expended) couldn’t move it into a parking orbit. There literally isn’t enough current lifting capacity on Earth to do this.

You're trying to calculate this with weird units. ISS escape velocity orbit would require about 3200m/s delta-v. Yes, with chemical rockets this is like 800 tons of fuel. But you don't really need the high thrust of big chemical rockets. You could do it with ion engines which have a specific impulse between 10x to 100x higher than chemical rockets, bringing the total cost way down. It would take much longer, but it could be done.
Yeah, but this is the ISS we're talking about. Obsolete commsat number 723, sure, no one's going to care about deorbiting it, but the ISS has historic and cultural significance. Raise it a bit to a parking orbit, everything else can keep track of where it is, and a thousand years from space archaeologists can explore it.

Or pack it inside otherwise empty Starships a few segments at a time and fly it down intact to put in a museum.

The ISS will burn up in the atmosphere within very few years unless periodically boosted up.

Boosting it all the way up to a more long-term graveyard orbit (i.e. several hundred kilometers) would consume a lot of fuel compared to a planned deorbit.

At one point they planned on using ion thrusters to try and keep the ISS in a stable orbit. I wonder how many it would take to push it into a graveyard orbit? Most of the energy for ion thrusters comes from solar, which the ISS has plenty of.
- "Most of the energy for ion thrusters comes from solar, which the ISS has plenty of."

The ISS rather has very low power relative to its mass. About 1/50th the power/mass ratio of the Dawn probe, for instance. This approach would take multiple decades, with the ISS as it currently is.

It's worth remarking there's never been a spacecraft to date that's attempted a solar-electric spiral out starting from low Earth orbit. (The Boeing 702 satellites can spiral from GTO to GEO at least—though those have, again, far higher power/mass ratios than the ISS).

A deorbit would create a huge amount of chemicals in the atmosphere that are very harmful to the ozone layer. It might be worth sending up a few more rockets to give a big enough push to send the ISS into the sun (along with said rockets).

https://www.space.com/starlink-satellite-reentry-ozone-deple...

https://www.space.com/deorbiting-impact-on-earth-atmosphere-...

Why the sun? In terms of delta-V that's the hardest target to hit in the entire solar system, since you have to zero out all of earth's orbital velocity.
My KSP-fu tells me that you could definitely get a corona-crossing periapsis without zeroing out the velocity relative to the sun. You aren’t trying to land on the bastard.
That much delta v would take a few hundred rockets, not a few. You’d probably cause way more pollution from all those rockets.
> Raise it a bit to a parking orbit

That's not “a bit” and the fact that it’s the ISS and not a typical satellite is among the reasons it is impractical.

It would take a massive amount of energy to eject such a huge structure from very low orbit out of Earth orbit completely.
Does it have the delta v and structural strength for a maneuver like that in its current configuration? I agree it would be cool to put it in deep freeze for a few thousand years.
Structural strength shouldn't be an issue, but it doesn't have the delta-v. They would probably need to find a way to attach some ion engine tug to it.
Can you imagine, people rebuilding the society after collapse and this thing resembling the images in some very old artefacts returns from the skies.
... moving at like a billion miles an hour before vanishing back into the blackness before humanity can react.
... that might explain Oumuamua!
can you protect an orbit with the "One Small Step to Protect Human Heritage in Space Act"?
Answered in their FAQ[1]:

> Decommissioning by boosting an object to a higher “graveyard” orbit to extend orbital lifetime is often done with smaller satellites operating near geostationary orbits (~36,000 km in altitude). This is not a realistic target for space station decommissioning because of the large mass of the space station and distance from its operational altitude to a “graveyard” orbit. Existing propulsive assets (spacecraft) do not have the capability to raise the space station’s altitude to such a high target.

[1] https://www.nasa.gov/faqs-the-international-space-station-tr...

For perspective, the ISS is currently orbiting at 400km altitude. Typical graveyard orbits are just beyond geostationary, so lets call it 36500km.

Orbits get somewhat emptier beyond 2500km altitude, but you'd still risk spent rocket stages or defunct satellites hitting the ISS if you don't go all the way out beyond geostationary. Maybe you can stay at lower orbits if you dock a vehicle that can provide thrust for obstacle avoidance even after the main station powers off.

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It's far more expensive, in the orbital mechanics sense, to do anything like that than to "simply"* nudge an end-of-life satellite just enough to push into the atmosphere, when it's starting from an already-low orbit.

*(The engineering here is not very simple)

> So...with $843M, what could SpaceX come up with? In Gwynne's shoes, I'd be looking to develop a vehicle with far wider application than a 1-off LEO deorbit burn.

So that would probably point to "Starship, possibly with a lot of fuel loaded onboard, docks with ISS, and then feathers its maneuvering jets to push the ISS into a guided re-entry into the Pacific Ocean."

Maybe the extra cost is to look into bringing it down without destroying it. Would be good to study it for data on long term spacecraft.
If anything I'd like SpaceX to attach some cameras that live-stream the ISS breakup through Starlink the way they've been filming their re-entries.
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> This highlights the sorry state of science and space exploration. We spent billions building this amazing station, and now we want to deorbit it? What a shame.

We learned a lot from it, but now it's outdated and crawling with difficult to eradicate mold and fungus.

With Starship, we could launch 100 International Space Stations.

We'll be fine.

> Space station mold survives 200 times the radiation dose that would kill a human

> that the spores could survive radiation doses of 500 to 1000 gray (=sieverts),

Humans can survive massive amount if radiation, provided it's not all at once (research sample size = 1).

Albert Stevens survived 64 sieverts deliverted over 20 years (lethal dose 50 % die in 30 days is 4-5 sieverts).

It's almost as if linear-no-threshold model is wrong and we do actually have some capability to repair some damage

Edit: just to clarify, survive doesn't mean thrive. Just that we might survive in a deadly environment better and longer than expected.

Linear no threshold refers to cancer not acute radiation sickness. People getting people getting a sunburn vs skin cancer from sun exposure are experiencing different biological processes, the underlying mechanisms are related but different.

Threshold dosing in terms of cancer has zero evidence to support it, and cancer is already really common suggesting if there’s any threshold we are well past it.

The only reason you hear about it is there is an industry who really wishes it were true. Just like people suggesting low dose exposure to lead wasn’t harmful when they want to sell Tetraethyllead in gasoline, monetary rewards cloud judgement. Same deal with tanning beds and just about any product exposing people to ionizing radiation, the risks don’t seem bad when there’s money to be made.

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> crawling with difficult to eradicate mold and fungus

Likely a problem for any future space travel e.g. to Mars? Why not use it as a laboratory to figure out how to deal with it?

Because labs don't often have their experiments growing uncontrolled everywhere.
Well, there was a lab in Wuhan a while back... ;)
It wasn’t designed for that. Presumably habitats intended to be long term will be.
> This highlights the sorry state of science and space exploration.

No it doesn't. Actually inform yourself. The station is old, hard to maintain and out of data.

The money free up from the ISS can then be spent on multiple new next generation stations that will be cheaper to operate and more modern.

Space is an incredibly, and unrelentingly, harsh environment to exist in. The station is literally rotting, and it's getting to the point where the things that are breaking aren't really fixable. It's time to ol'yeller it and build something else. This isn't your classic car that can be restored to like-new condition, this is orders of magnitude more complex, and it's an incredible feat of humanity that it's lasted as long as it has.

It's not really a waste of money inasmuch as, the things you put into space are consumables, and you have to replace them before they turn back into dust.

Also, as a complete aside, and unrelated to any of the above, why do you think we left all that hardware in Afghanistan? Don't you think we could have recovered at least almost all of it if we'd wanted to? Because it wasn't like we were really having a ton of hot combat at the time. And, if we could, why didn't we? It certainly wasn't cost, the MIC has the unlimited money cheat turned on so cost isn't a factor in anything really. Couldn't have been public perception, being that it was almost universally viewed as a blunder. When I look at it though, I don't see a blunder, I see a strategic move. Have a look at a map, who's next-door neighbors with Afghanistan? Iran. Does Iran get along with Afghanistan? No. Why don't they get along? Afghanistan is overwhelmingly Sunni Muslim, Iran is overwhelmingly Shia Muslim, and those two groups HATE eachother. Iran, by far, as the better military forces, so, if you want to keep those two countries busy murdering eachother for the foreseeable future, well, you "give" a bunch of semi-modern military hardware to Afghanistan, obviously.

So the real question is how much is that strategic move worth? It's cost somewhere ~6 trillion dollars since 2001 to run military operations in the middle east. We left ~8 billion dollars worth of hardware in Afghanistan, so, if that strategy works, well, it's substantially cheaper than just fighting a hot war with Iran, probably by a few decimal places.

This is the most optimistic spin I’ve ever seen on how we pulled out of Afghanistan and while I’m not sure I believe it, I kind of want to.
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It's the only way I've found to explain it that actually holds up to scrutiny. That's not to say it's correct, just that it's the best I've found.
You have a compelling argument. The only reason I’m suspicious of it is that it is just that compelling.
It isn't even remotely compelling if somebody knows anything about the region that doesn't really on a bunch of ignorant tropes.
> Afghanistan is overwhelmingly Sunni Muslim, Iran is overwhelmingly Shia Muslim, and those two groups HATE eachother.

That such a hilarious oversimplification. You are just bumbling into a highly complex issue throwing around generalizations.

The issues between Iran and Afganistan are overwhelmingly about water rights, not some religious battle.

Iran supports different groups within Afganistan, including Sunni and Shia.

> if you want to keep those two countries busy murdering eachother for the foreseeable future, well, you "give" a bunch of semi-modern military hardware to Afghanistan, obviously.

Except Afghanistan is not using those things to fight Iran at all. There is no hot war. Afghanistan can't really operate that stuff anyway, what they do is simply sell it as parts to finance the government.

And as it looks right now, a war with Central Asian countries that the US certainty wouldn't want is far more likely then a war with Iran.

> When I look at it though, I don't see a blunder, I see a strategic move.

If you want to 4D galaxy brain yourself out of any bad choices by the government you certainty can but its just complete nonsense.

The reality is these process are simply not planned out. Communication between militarily and politics are terrible. Sometimes things just are what they are.

Why not re-orbit? If $2B could be used to keep it going another decade, would we do that instead?
Operation costs should increase as more and more parts start breaking down. It’s an old station by now.

That considered, it feels wrong to not extend its life until it actually is cheaper to replace it and, then, do so module by module.

The spacecraft equivalent of refactoring vs rewriting from scratch.
I'm wondering how hard it would be to boost it to a long-term stable orbit and then empty it of it's atmosphere and just preserve it as some kind of a museum piece basically. Of course, for the near-to-medium future, such a museum piece is completely useless to anyone. But hopefully that won't always be the case.
The hoarding instinct because space is big!
Like a space landmark. A spacemark? The San Francisco Cable Car museum makes a big deal about the Cable Cars being the only moving designated landmark (dunno if that’s still true, but it was when I was a kid), but in terms of speed the ISS has those rickety little boxes beat.
Not sure it’s a good idea to just boost it. It would be impacted more frequently and release more material from the impacts, furthering the problem.
Probably because structural materials are reaching their age limit, and things like preventing mold are just going to keep getting harder and harder. Sure, the station could be re-orbited, but maybe it is better to spend that money on something new instead of just refurbishing the old station.
The thin aluminum pressure compartments are the biggest issue I'd imagine; they can only handle so many heat/cool cycles orbiting the earth before the material fatigues and fails. You'd have to replace them all if you want the station to continue, at which point you're essentially building another station.
Because another decade would cost another $35B and NASA's got other places it wants to spend that money.
If we are going to continue to use it at all I think it would be better as a platform from which to build a completely new space station/platform. From what I understand it is pretty fragile at this point and retrofitting it is always going to involve compromises and likely cost more in the end.
It would be an interesting challenge to try to re-orbit and recycle it.

I really want to hope some day we get up to space (or moon) manufacturing, so we can build amazing things in space. Having such a large set of raw materials already in place, to pick apart melt down & reuse would be a neat way to jumpstart space recycling sustainability.

Ideally we could leave it derelict & decide in 10, 20, 100 years, hey, yeah there is plenty of raw material here we want to go after. Trying to do anything now with it sounds expensive, yes. But if we could leave the option open, like a landfill we can latter go reprocess if the economics change.

> Ideally we could leave it derelict

Not possible. The ISS is in a low enough orbit that it experiences atmospheric drag and requires periodic reboosts to keep it where it is. Left alone, it'll deorbit on its own, potentially over a populated area.

with or without the Boeing Starliner Max still attached? :D
I wonder if the truss and other components could be harvested. Move to lunar orbit.
Wow didn't expect this to go to SpaceX.

$843 seems like way to much money for this job. Seems like about 400 million $ of that would just be mission assurance.

The whole Falcon 9 program didn't even cost 400 million $ to develop initially. That includes developing a new engine.

Unless there are some crazy requirements here that I don't see, this is a great deal for SpaceX.

If SpaceX got it for $843m, doesn't that imply it would've cost everyone else a lot more?
$843M is the contract cost, basically to just do the R&D. The vehicle itself will be sold separately.
> The whole Falcon 9 program didn't even cost 400 million $ to develop initially.

The Falcon 9 first flew in 2010. US govt CPI measure over the period 2008 (picking a development start time at random) to 2024 is ~45 percent. I've not idea if this explains it all, but it certainly explains a chunk of it.

Who else is there at the moment? Boeing who people don't even trust in atmo, and the russians who we're in a cold war with?
>$843 seems like way to much money for this job.

The NASA Administrator quoted a $1.5 billion figure, so $843 million is a bargain.

Here's hoping launch costs fall quickly and it gets absorbed and rebuilt as a much larger station, Ship of Theseus style.
This is exactly what happens in Valerian and the City of a Thousand Planets.. the opening to that movie is fantastic. The rest, well I don't remember so it must have been forgettable

https://www.youtube.com/watch?v=u0FX8sd1uVo

It would be very sad if this wasn't one of the possible fates of ISS.

Ah that's super neat. Hadn't seen this before. Thanks!

Here's hoping :)

Aren't they far behind on their Starship milestones? Why would Nasa grant them more contracts?

https://i.redd.it/x998dcfi8sz71.jpg

No one expects Elon timelines to actually happen. Also, the other option is... Boeing? And they're doing SPECTACULARLY well right now. In Space, on a plane. If it's Boeing, you're better off not going.
They are made for each other. NASA's not so good with their Artemis schedule either.
They've been pretty reliable and cost effective for delivering people/cargo to the ISS so far. Even without Starship they can probably pull this mission off.

FWIW that image also shows Artemis III launching early 2025, but NASA has delayed that to 2026 at the earliest (unlikely), so it's not like SpaceX is holding up the mission.

SpaceX delivered their commercial crew contract with 3 years delay, Boeing is currently on the 7th year of delay and running. NASA's SLS was delayed by nearly 6 years despite being conceived as the "easy and safe option" of combining shuttle parts in the shape of a rocket.

Rocket science is hard, everyone missing their milestones is almost expected. And SpaceX is among the more reliable partners available to NASA.

RTX Collin's just gave up on their spacesuit contract. So there's a good chance that'll delay Artemis by a good 5 years or so.
They still have Axiom working on spacesuits: https://www.reuters.com/technology/space/rtxs-collins-talks-...
Ars has a lot more detail in this article: https://arstechnica.com/space/2024/06/nasas-commercial-space...

It seems Axiom has been focused on a suit for Artemis interior and moon operations while Collins was specifically developing one for in-orbit EVAs, which is a separate beast.

Assuming they hand full reigns to Axiom, congrats to that team! But it does seem likely this means delays, as they now have to develop an additional suit for an additional and distinct use case. Good time to be job hunting in this field, perhaps.

For those interested, Cleo Abrams recently put out a great video testing an Axiom prototype and discussing many of the design challenges being worked on with the Axiom team.

https://youtu.be/FerFv7BZAwo

The timelines (and budgets) are just what you say to get congress or the general public to go along. I'm sure everybody actually directly involved, and probably most congresspeople as well, know these timelines are unrealistic. At least this gives the congressperson an out: "XYZ is to blame! They're way behind schedule!"

Read Power Broker to get a real sense of this. Such a great book.

Because there is no company that they could give it too that has both experience and a better track record.

Its like saying why are you using linux, don't you know it has a knowing history of having bugs. Sure, but show me the alternative that never had bugs.

This tug not working correctly could mean dropping the ISS on a major city. So they are not gone trust some new unproven company. And there are simply not many companies that can do that stuff.

Being late on a highly complex experimental project is totally different and a different part of the company. This tug is much more likely to be derived from their existing Dragon contracts and those have an amazing track record of execution in the last decade.

Wouldn't the ISS make a nice station for Lagrange Points 4 or 5?

Hell, why can't we use it as the Lunar Gateway?

No and no.

* At the time its decommissioned it will be over 30 years old, well past it's original planned lifespan.

* It was never designed for orbital maneuvers with that much delta-v.

* Due to how adjusting orbits works, it would require about as much energy to move it into such a different orbit as it would to just ship a new one from Earth. This is even more true when you consider we would have to ship all the fuel into orbit to perform the orbit shift.

No one ever understands how far (in energy) different places (orbits, its all orbits) in space are and what that implies about moving stuff from one to the other.
I understand this conceptually, at least that moving from one orbit to another is very costly in energy. But what mental model can I use to get a rough idea of which things require more energy vs less? Or maybe what contributes to that energy requirement?
The component of your velocity that isn't coplanar with the orbit you want to end up in is velocity you have to get rid of.
I don't get the delta-v argument: now that it is in orbit outside the atmosphere, we can accelerate it as progressively as we want, e.g. with ion thrusters or solar sails, to raise its kinetic energy until it reaches a higher orbit, no?
I concede that I was assuming a traditional chemical rocket to generate the force. A more gentle force would put less strain on the structure.
Still cheaper than the Baltimore Bridge
It's a shame this has to happen. I always hope that something could be salvaged and used for Lunar Gateway, or... something. It's still my hope that NASA uses the remaining return trips to bring back as many "souvenirs" as possible. The unfortunate reality is that it probably doesn't make sense to do anything with the station other than de-orbit, with the declining costs and the age of whats up there.

When ISS was lofted the cost to get into space was crazy high. 1981 Space Shuttle was $65k per KG to LEO. Falcon 9 is somewhere in the range of $2500 per KG to LEO. Falcon Heavy is even less than that at around $1000 per KG to LEO. It wouldn't surprise me if Starship is even cheaper.

So why spend millions of dollars trying to "save a buck" on components when you can launch newer/better/stronger/lighter (ex: Sierra Space's LIFE Hab) for orders of magnitude cheaper than you could "back in the day".

Plus the entire station getting past its design lifespan. And while the ISS was able to apply a lot of lessons from Skylab and Mir on things like mold growth, I imagine the ISS has accumulated its share of problems too and provided a lot of lessons for future station designs.

As an asset it's only logical to replace it. It's only contentious because of the sentimental value attached to the station.

As a layman space exploration enthusiast, I'm just worried we'll treat this like the moon, where we get rid of the existing very cool and exciting thing keeping us in space, and don't replace it for a long while.

The ISS has been a beautiful international collaboration for decades and it'll be a shame to see it gone.

I disagree about it being logical to replace it. There's no real good reason not to keep it if we think it's still useful. I feel it's contentious because that's a lot of money to spend destroying stuff that could still provide benefit for many years to come.

Of course, to actually discuss this, we need to answer the real question of whether we even want to keep the ISS...

If we agree something like this is useful to have in the long run, if we destroy the old one, we have to get every party involved (or a new group of countries) to agree that this is worth spending the money on building an entirely new ISS. My gut feeling says that won't happen in the current geo-political climate. If we destroy the ISS, that's the end of the road.

We could, of course, all agree that it's too expensive maintaining the ISS and we should just abandon any such future projects. While this might well be popular with some governments trying to save money, we will miss out on all that research and international collaboration. Honestly, I don't know what value that research is nowadays, but I assume there must have been some or we wouldn't have done it originally and manage to convince lots of countries to participate in spite of their ongoing tensions.

Or the third option - continue to build, using the existing ISS as a base. We could send up small modules piecemeal and bolt them onto the ISS. It's not like the ISS even has to end up as the centre, it could end up entirely on one side and at the point it's really no longer useful for operations, it would still have value as a storage space, the parts could be ransacked for repairs, it would even provide some impact protection from random space junk.

Other than potentially making the "new" ISS a bit less maneuverable, or random bits falling off and hitting the new structure (not sure if that really happens or only in movies), I don't really see any downsides to keeping the old ISS attached to any new structure. And keeping it safeguards us against completely abandoning future co-operative research.

I guess one perceived downside might be that the US wants to go it alone with some secret projects, and doesn't want to build anything attached to the ISS to reduce the possibility of a hostile takeover.

I don't get how spaceX builds it, but NASA "owns and operates" the vehicle. Surely spaceX rockets are chock full of proprietary internal tooling and services. They are an almost totally vertical company.

Does SpaceX just open their stack to NASA? Or does SpaceX just provide an 'api' layer of control, making this 'own and operate' a weird almost anachronistic distinction?

I’m sure this is all spelled out under some commercial partnership agreement
“Own” is likely a very simplistic term for the complex agreement in place between SpaceX and NASA. I’m sure SpaceX retains all of the developed IP, but NASA can “do whatever they want” with the actual ship.
I don't know, but it seems like this sort of thing is perfectly normal for military contracts, so why not for NASA?
Maybe "operating" only means NASA makes the decisions, but mission control is outsourced to SpaceX? Alternatively it could be part of the contract that SpaceX provides everything needed to operate the mission, as well as training for NASA personnel on how to use their stuff, as well as providing people on standby for "troubleshooting and tech support".
Both my computer and my car are chock full of proprietary internal tooling and interfaces. My evaporative cooler and its thermostat are a proprietary bundle with undisclosed internal communication. I'd like to think I still own and operate all of those.
Why don't they deorbit it to the moon? That way it's debris field can be a monument/grave site.

Hell this is spaceX, why don't they just land the thing on the moon in tact?

For one, the distance to the moon is about 1000 times the distance to earth.
Yes but earths gravity affects it at r^2 so it's like log(1000) scale energy not 1000x
They would need several space stations to iterate until they would be able to nail it.
Is there any benefit landing it on the moon, create a yard of space junk and extra parts for future bases...never know....
It is sad that ISS exists at all. After the Mir the world should have gone rotating station route - the next logical step. Instead we have wasted so many resources on something that has already been done before
Feels like folks are not making enough money maintaining the existing space station, so they need to get rid of it to make way for the next $100B space station project.
Except that if you actually bother to look at the current plan, NASA wants to invest much less in the next generation station. Private companies will run and operate them. NASA will only rent spaces for astronauts.

The next generation stations are also smaller but will be launched in much larger chunks, making the price per volume much cheaper. And much more modern operation.

NASA absolutely will not invest anywhere close to $100B in those projects.

NASA budget will mostly shift to moon stuff.

The fall of the ISS will be a symbol of some kind that’s for sure
Can’t they … ‘demodulate’ it? And bring it down (or up) in pieces? Maybe reconfigure a “mini iss” out of it. Like a giant Lego set. Ultimate off grid micro space station. Or boost key sections really really high…for reasons.
The Gigachad move would be to land it, but of course that’s not even theoretically possible or worthwhile
Starship might be able to land on Earth with ~50 tonnes of cargo, maybe less. A rocket with 10x the capacity of Starship would be truly impressive.
For those unfamiliar with orbital mechanics & aerospace engineering, who wonder about raising the ISS into a much-higher (long-term stable) orbit, or fixing it up and continuing to use it:

Trying to raise the orbit: The ISS orbits very close to the "bottom" of the zone of vaguely-stableish LEO orbits. Really-stable, "vacant" orbits, suitable for long-term inert storage - those are far, far higher. Think of having a reproduction Viking longboat on the beach. Pushing it "down", into the sea, is work - but not too much. Vs. if you wanted to push that longboat uphill, to an elevation of a few thousand feet? Vastly more work.

Trying to keep using it, long after the lifetime that the Materials Engineering & Mechanical Engineering experts designed it for, might turn out like this:

https://admiralcloudberg.medium.com/falling-to-pieces-the-ne...

- except with all the astronauts dead.

As complex structures under load (like pressurized ISS modules) age, the properties of the materials they're made of change - often for the worse. And microscopic cracks form & grow, joints (intentional or not) work and wear, inelastic deformation accumulates and shifts stress to areas not designed to withstand it, and so on.