NASA plans to retire the ISS by 2031 by crashing it into the Pacific Ocean | Hacker News Reader

NASA plans to retire the ISS by 2031 by crashing it into the Pacific Ocean

cnn.com

36 pointsjeffwass62 comments

I believe it when there's a replacement launched, it's been about to be decommissioned for the last 2 decades with the same idea that there will be a commercial station to replace it and it always gets pushed back because space is still too damn expensive for anyone other than a government to put people up there. Maybe NASA's hand will be forced by the slow degradation of the structure from heat cycling causing leaks and cracks we're starting to see, but I think that's more likely to wind up with a break in this continuous habitation streak than with a proper replacement.

The entire ISS could be launched in 3, maybe 4 SpaceX Starship launches assuming Elon is correct about his claims for the payload.

To put in in perspective, the ISS required 36 Space Shuttle launches at a cost of $1.5B per launch ($54B). For that cost, assuming a pessimistic cost for Starship of $10M per launch (5,400/4 launches), you could launch 1,350 International Space Stations for the same price as the ISS cost to launch flying on the shuttle. To me it sounds not only realistic that we would launch a replacement but surpass it by 100x or 1000x.

We have come a long way from the late 90s and early 2000s when ISS was built. If NASA was properly funded I'm sure it would also be able to build a competing station cheaper/easier as well. ISS and NASA paved the way for SpaceX. So them being to do it cheaper isn't as impressive as it was bound to happen.

That would also be the first time Elon is correct about his claims, then.

His claims about falcon 9 mostly line up with reality.

Launching isn't the only thing you need to do to build a replacement, there's building it twice: once on Earth and again in space. The ISS was assembled largely by hand by astronauts working out of the Space Shuttle which has an airlock that none of the current capsules have so they'll have to work out of a seed station launched in a single go or we'll have to wait for a crew Starship. That's a long ways off even if you don't account for Musk's habit of promising things are coming soon.

The cost of the ISS was not just the launches. The modules themselves were massively expensive to design, build, and test before they ever made it into a payload bay. For example, the Tranquility + Cupola modules together cost $400M just to build. This wouldn’t change that much just because the launch costs go down, even with newer tech (Bigelow modules would still cost on the order of $100M a pop). If you want to put humans in space for long periods of time without killing them, the things you put them into are going to be complex and expensive.

To me it would make a lot more sense to boost the ISS to a higher orbit so future industry can repurpose the materials on it, rather than throw the entire thing away because it’s old.

The ISS was years from being finished two decades ago. It was still getting new modules in the 2010s. Your timeline is way off, so you might want to double check whatever your basis is for thinking this is a recurring call over two decades.

For historical context: the first module didn't launch until November 1998. The Cupola everyone loves to see in photos was 2010. The current tech boom is older than the finished ISS.

Feels like longer but the date is always changing just recently back in 2018 the plan under the Trump admin was to halt funding in 2025 [0], in 2008 the planned date was 2016 [1]. It seems like the decommissioning is always planned for the next administration to deal with.

With anything space in particular I don't hold my breath for anything planned beyond the current administration unless it's something fairly small like a rover or satellite [-1] because every administration comes in and wants to have their own project be the one so they "reevaluate" and "reassess" the plans to make them more or less grandiose as suits their current economic stance.

[-1] They're usually small enough they can get a nice big cash infusion right up front so there's a sunk cost to keep funding where plans are relatively cheap.

[0] https://spaceflightnow.com/2018/05/20/nasa-wrestles-with-wha...

[1] https://www.govinfo.gov/content/pkg/GAOREPORTS-GAO-08-581T/h... ^F "planned decommissioning in fiscal year 2016."

Idea: gently boost it into a much higher orbit, leave it there and designate it as (one of) the first Space Heritage Site(s).

First? Neil Armstrong’s footprints on the moon already are somewhat protected (https://astronomy.com/news/2021/01/neil-armstrongs-bootprint...)

Wouldn’t that be a _lunar_ heritage site, not a _space_ heritage site?

Well, the moon _is_ in space...

;)

You need to keep it fueled for it to maintain whatever orbit it gets pushed into. Orbital decay and everything.

If the orbit is higher it can last for thousands or millions of years

Orbital decay comes from something. At some distance from Earth, you run out of somethings (most critically: atmosphere) decaying an orbit.

So past a certain distance, orbits are effectively "forever" ones.

It just takes more energy to get there, which is why the ISS is where it is.

I don't think it can just be a "gentle" nudge, it is a massive body and must need a rocket-level thrust to do so, but really, I agree with the idea. Why not?

Dock a custom Dragon with thrust capabilities, put in a higher, more stable orbit. Doesn't even has to be circular, just so we can visit it in the near future.

Well in theory it could even be done with the station keeping capable modules, a very gentle push indeed, it would just take time and maybe refueling..

Pretty sure you can ion thruster it if you are patient

If I remember correctly, a constant thrust of only 5 Newton (for comparison that’s the weight of a mass of 0.5kg on Earth) would be enough to counteract drag of the atmosphere on the ISS. That’s in the range of an electric propulsion systems like VASIMR that is under active development. Any higher thrust than that would automatically lead to orbit raising.

Progress can boost because it docks on Zvezda. Dragon doesn't, so you'd need a new docking method.

There was a proposal to use a VASIMR ion engine as an experiment to boost ISS, but that proposal was dropped a few years back. Had it been kept and worked then perhaps it could have worked, but it used a lot of electricity to do so

The ISS takes over 10% of NASA's budget at over $3b/year in maintenance, so they won't be able to take care of it and sustain their proposed moon mission at the same time. Plus the low-hanging fruit for research has already been performed. My unpopular opinion is that manned spaceflight is an expensive national vanity project for modest research gains, and the projects that have been most successfull from a science perspective have been the deep space probes/space telescopes.

> modest research gains

You also have to add in the PR benefits of each. If children aren't interested in space today, there won't be any government funding for space missions when those children become voters.

In that light, dropping manned missions entirely will probably reduce interest in space quite a bit. Probably moreso than a rover on mars that figures out the composition of some rock.

> Probably moreso than a rover on mars that figures out the composition of some rock.

Over the past 20yr hose rovers had gone from "testing the composition of probably dead rocks" to "actively looking for signs of current or former microbial life". Even the landings have gone from "shoot the thing at the planet and wait to hear back from it" to a live-streamed helicopter drop. I think they've excliped the ISS in terms of excitement for the junior-high and above crowd. Skyping someone in a blue jumpsuit who's floating around in a tube doesn't have the cool factor that "literally on another planet" gets you.

I never understood why a free-fall from space with a parachute would not work. (I bring this up because I would propose bringing down sections of ISS with extremely large parachutes.)

I get there is no air in space, and how thin it is as you approach the Earth's surface. But it is a gradient after all.

If a falling body begins to heat up, that suggests it has entered a region with some atmosphere — and so some parachute utility.

In my mind the effectiveness of the parachute would track the rise in atmospheric density — just as the rise in atmospheric density became a heat issue. In other words, the parachute would slowly become effective, enough so to keep the falling body from ever attaining a speed that generates too much heat (with regard to the density of the atmosphere it is traversing).

How is the model in my head wrong? Does the parachute effectiveness lag with regard to the rise of the "heat gradient"?

My guess is that your idea is right, but the gradient is just not smooth enough.

Size of parachute for the ISS is prohibitively large.

Heating is all concentrated on a single profile.

> I never understood why a free-fall from space with a parachute would not work.

It depends what you mean by "from space". The ISS is in space and also _in orbit_, so is moving laterally at about 17,500 mph / 28,000 km/h / 7777 m/s / Mach 22 (1)

It's not just about falling, it's about the heat and stress of hitting the air when moving sideways at nearly 8 kilometres per second.

The "sub-orbital hop" scenario that Bezos and Branson do involves technically "falling from space" but is very different as they're not moving sideways.

1) https://www.space.com/16748-international-space-station.html

> How is the model in my head wrong? Does the parachute effectiveness lag with regard to the rise of the "heat gradient"?

Consider that landing on Mars is difficult: it has enough of an atmosphere to be a problem (lots of heat on re-entry), but too thin to be useful (limited drag).

With that in mind, my guess is that the ISS would heat up faster than the parachute would slow it down.

Basically yes things start falling out of the sky faster than you can slow them down to avoid burning up causing them to fall deeper into the atmosphere where the parachute just gets ripped apart or your spacecraft just melts from the friction of slamming through the atmosphere at Mach 20+. Orbiting objects are just going way faster than you can slow down with just a parachute you have to have something in front to protect the craft, so far they're all heat shields of some sort either ablative or extremely insulative so the flimsy spacecraft doesn't become a giant piece of slag.

One of the big problems with landing on Mars is related to this. The atmosphere is thick enough to cause heat problems but thin enough that slowing down enough to deploy a parachute is hard so we're limited in the amount of mass we can send until we figure out inflatable heat shields to increase the cross sectional area so we can slow down enough for parachutes to work. Otherwise you have to use a Starship style powered landing all the way down. With that you have to carry all that fuel to Mars which again cuts down on the mass you can actually land.

I think part of the problem is that there is a regime where the atmosphere is too sparse to really act like a fluid or carry away heat. The kinetic energy of the falling object ultimately has to get converted to heat, but the balance between the power delivered to the spacecraft and the power dissipated back to the environment changes significantly with altitude. I think that period of only being able to really dissipate heat by radiation is what motivates the use of insulating tiles. That way the hottest surfaces can be allowed to reach high temperatures without harming the sensitive parts, and the power emitted scales as the temperature to the 4th power, so letting a small part get very hot provides better cooling than spreading that energy evenly out over the whole spacecraft.

You’d need a parachute designed for very high velocity[1] which does exist but this is still likely unreasonable. Heat goes up much faster than drag relative to speed.

1. https://en.wikipedia.org/wiki/Ballute

The idea has some theoretical merit to it, but the math doesn't add up at all when you run the numbers. The size and strength of the parachutes you would need would be massive. Much bigger than anything today. Don't forget you also need to bring up the parachutes and somehow attach them to the iss in a way where the stress of the deceleration won't snap the iss in half (hint: not possible).

I think this is better demonstrated as a smaller scale thought experiment. Consider the various space capsules over time, from Mercury & Apollo all the way through to dragon. They all use parachutes, but not until late in the landing process. That's because they all use the upper atmosphere as a method of slowing down, and they can't use a parachute up there because, again, the numbers don't work.

The problem is you are moving on the order of 20,000 mph laterally, you are not just falling straight down. You could make this work with something sufficiently large and light though. Like if the ISS were made of only carbon fiber and emptied of everything, maybe.

I wonder if there is a way to ditch the ISS without contributing to oceanic pollution. I get that this is likely a low-cost solution (disassembling it and transporting it wouldn't be cheap) but it would be nice to not contribute to the trash already floating around.

As long as you remove any toxic stuff ahead of time, dumping the metal isn't so bad. It will become a thriving ecosystem on the ocean floor.

Crazy idea: are there enough space nerds who would pay for a small momento piece of ISS that it might be worthwhile to disassemble it in space and bring parts back to Earth?

Even if you broke it into thousands of pieces and brought it back I think the cost would be astronomical. You've got to launch a craft up to take it apart and bring pieces back, potentially multiple times, compared to the cost of just blasting it into the water.

> the cost would be astronomical

Absolutely. But, I think we may be also be underestimating the size of the market for things like this... Just search for Enron coffee mugs or pokemon cards on Ebay.

No but a kickstarter to take a ship, and drag the ocean for the pieces would be cool.

The ISS routinely discards thrash by placing it in returning Soyuz capsules which would otherwise return empty. I wonder if there's a market for this thrash.

Why not leave it and add more and more modules over time, until it is a giant space city?

It needs to be boosted every month or so or it will be dragged down into thicker atmosphere.

Because it keeps falling down to earth due to the (very thin) atmosphere at that altitude slowing it down. To counteract that periodically it's boosted by a visiting Russian spacecraft, however that won't last forever. American spacecraft don't dock in the right location to allow the boost.

On top of that, old things require constant and increasing costs in maintenance. At some point it becomes more economical to build a new one than keep an old one running.

And in any case the value of keeping it running has to outstrip the cost of keeping it running, with the cost increasing, and the value not (It claims it's international, but China isn't involved, they have their own space station. With blackjack and hookers), and Russia can't afford it.

By 2031 SpaceX will hopefully have an orbiting Starship, that craft alone has an internal volume around the same as the entire Space Station's pressurised volume. If Starship is successful, a new station based on launching and docking skills built through the starship program, will be far better value for money.

But what happens if the Chinese recover pieces of it from the ocean and figure out how to waste trillions of dollars to no good effect too? /sarcasm

Wouldn't we have been much better served using all that money to figure out how to manufacture more/better microchips? The StarTrek fantasy will still be there in a century or two.

Ignoring your sarcasm and focusing on your second point :

One big example is SpaceX. I don’t think they’d be as successful as they are right now if they didn’t have some of that initial funding from NASA to help them bootstrap to where they are today.

This is one stellar example of how federal research funding dollars can generate positive societal benefits through the transfer to private industry.

Of course there are some companies that just siphon federal dollars without much to show in return, but for SpaceX they have really returned multiples on those initial “investments”.

I think you just found a mission statement for NASA that congress can get behind: Welfare for Billionaires.

So we need the ISS so we can use taxpayer money to fund billionaires to develop rockets to launch to the ISS?

See here: https://en.m.wikipedia.org/wiki/Circular_reasoning

Where would we be without SpaceX? Pretty much where we are now --- struggling to find enough chips to build cars and Raspberry PIs.

It would be nice if we could do both.

Yes. But unfortunately, the one being addressed won't have any real impact for generations while more immediate needs are being ignored.

NASA has spent trillions studying the effects of weightlessness on people.

In comparison, they have spent virtually nothing on protecting the plant from an asteroid strike or mitigating the effects of global warming --- both of which are way more pressing concerns.

Studying people in space is about as practical as addressing global warming by funding research on Dyson spheres.

Global warming, I agree, should be everyone's highest priority.

Asteroid strike ... hasn't it been a while since the Earth has seen one on a scale that would rival global warming? Worrying about an asteroid strike seems like something that has stirred the public imagination but has a crazy low likelihood.

It's been a while --- but most scientists consider a significant asteroid strike to be a near certainty --- they just can't say when. Based on *known* asteroids, the probability by 2300 has been calculated at about 1 in 2000.

But don't relax just yet, we find previously unknown asteroids all the time. Just last year, one (2021 UA1) flew by Antarctica undetected until after it has passed at a distance of about 1400 miles.

But even if we detect one, there is no real working plan in place to try and deflect it. Thanks NASA --- this is why we give you the big bucks!

Physicist Stephen Hawking, in his final book, Brief Answers to the Big Questions, considered an asteroid collision to be the single biggest threat to the planet.

While HN complains that we want cars without chips to begin with.

HN is just a web site where people can post opinions. "HN" doesn't complain --- you can't reasonably attribute one post to "HN".

That was 2 days ago?

Please make a dumb car (techcrunch.com)

https://news.ycombinator.com/item?id=30144101

Chips? We need more crisps

The ISS is a microgravity lab, and allows experiments in i.e. growing crystals. That's far out of my area of expertise, but it wouldn't surprise me if it eventually yielded some application in microchips.

There's research that can only be done in space because the microgravity allows smaller forces to be isolated and studied in ways they can't be on Earth. For one example they can grow protein crystals better up there which allow studying their structure and finding medical interventions to treat the diseases associated with them.

https://www.issnationallab.org/iss360/probing-proteins-lever...

So there is a "protein crystal disease"? How many people suffer from this?

Yes lots of diseases manifest as malformed proteins, to understand them you need to know the structure of the protein which is commonly done using x-ray crystallography which requires growing a crystal made of the thing you're studying. It's the way we learned the shape of DNA and a fundamental process for studying a lot of biological systems. Growing those crystals is tough on Earth because of gravity so they grew some on ISS they'd never managed to grow on Earth.

...they grew some on ISS they'd never managed to grow on Earth.

It's nice they were able to grow some crystals that never occur on earth because of --- gravity.

But is this valuable in any way back on earth? Highly doubtful. Probably about as productive as funding for an anti-gravity device on earth --- which the military is doing by the way.

I've said it 2 times now basically but I'll spell it out I guess. With the crystals they can determine the structure of errant proteins and develop treatments to target them to help people with the diseases these proteins create. Without the structure of the protein this is on the scale of extremely difficult to impossible.

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