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There was a Korean movie about a vaguely similar topic: salvaging space debris that I enjoyed

https://www.imdb.com/title/tt12838766/

That's a great movie!

There's also Japanese anime series set in the near-future sci-fi about a small company that cleans up space debris, called "Planet ES"

Its actually called Planetes, which means "wanderers", and was the term the ancient Greeks used for the "wandering stars", i.e. other planets. I cannot recommend it highly enough! It starts out pretty slapstick, but if you're looking for something more thoughtful, just stick it out until after the ninja episode. I promise it's worth it.

Slice o' life in space, cleaning up trash. What's not to like? :)

Planets is amazing, through-out singe-season story with an unexpected bit of drama and similarly unexpected resolution with a twist.

Planetes is one of my favorite anime series. I think it's very well done. I highly recommend it!

Edit: If you have trouble finding a way to watch it [it's a bit obscure] please shoot me a dm and I can probably help you out.

Thanks for the suggestion. I do like Anime so I’ll definitely be tracking this show down

There is also a manga and anime, called Planetes, which is about salvaging and removing debris:

https://en.wikipedia.org/wiki/Planetes

And schlocky 70's American TV:

https://en.wikipedia.org/wiki/Salvage_1

At the speeds those things whiz by, what sort of materials are there that can withstand impacts and not create more debris? Or do they try to do it via relative speeds and say let them hit the "paddle" at 50mph? And in that case, might it not be more effective to have hunting "nets" to collect the objects?

First, a lot of space debris is small. I'm talking like flecks of paint. That's an issue at high speed and this has hit the ISS [1].

Obviously there's the conservation of momentum to deal with. That fleck of paint has a decent amount of momentum but that's fairly easily absorbed by a couple of tons of material fixed to an otherwise rigid body.

You'd probably attach it via cables and if, somehow, enough momentum was delivered to that "paddle" that it would tear off the cables would just let it go.

If the paddle is fixed to the ring and is let go, it's just going to fall to Earth even with any added momentum, in which case it'll burn up in the atmosphere.

The more dangerous debris is larger stuff. Like there are dead parts of rockets, even smaller stuff like bolts. These pose extra challenges but a lot of the same principles apply.

[1]: https://www.csmonitor.com/Science/2016/0513/Space-debris-dan....

I thought larger parts aren't as big of an issue in the majority of cases as most orbits aren't stable and they'll eventually fall to earth or be ejected into outer space.

Maybe not hunting nets per say, maybe just a huge trawling net, or some sort of trawling-foam since we're in space. As high velocity objects begin to hit it, the foam will gain speed, but overtime, with presumably random speed-object collisions, the foam and its captured contents should have their speed reduced to 0 and fall. Doesn't need to be in foam or net form, but it does need to be a massive-entanglement-object, or MEO for short.

I'm probably under thinking this, but wouldn't the overall momentum of the debris be conserved so you'd have a bias in debris velocity in whatever direction the original objects were orbiting (presumably not random)?

I would assume that as the debris cloud became more biased in one direction, it would be more and more likely to encounter new debris coming in a different direction.

This would be a really fun simulation to run

At least at geosynchronous altitude it seems like it would be significantly biased in the direction of Earth's rotation, especially along geostationary orbit.

Maybe use lasers to ablate material on the debris, creating propulsion? Creates liability, though..

Splitting small things into slightly smaller things would only compound the problem

if you are moving with the almost the same speed and in the same direction as the debris, then there is a very small impact.

I imagine orbital velocities of debris is all over the place. It sound like you would need a magic source of thrust for all that delta-v to match orbits and whatnot.

The closest we have to that would probably be solar sails. Considering that cleanup usually isn't time sensitive it could be a very cheap and effective solution.

they might try out solar powered ion engines. Deep space one is powered by an engine of this type, see: https://en.wikipedia.org/wiki/Solar_electric_propulsion

Everything in an orbit moves at exactly the same speed.

https://en.m.wikipedia.org/wiki/Kepler's_laws_of_planetary_m...

You can only collide with an orbiting object if one of you is changing orbits.

It's very difficult to force to objects to meet in orbit with nearly the same velocity; it requires complex active maneuvering.

There are small debris clouds, but also large uncontrolled spacecraft, like boosters. De-orbiting those could be a huge help, since a collision with a stray booster would create gobs of debris so those orbits may be completely avoided.

Things that are not rigid and that distribute the force throughout the body (think of slapping a big slab of silicone).

Whipple shields

https://en.m.wikipedia.org/wiki/Whipple_shield

This could work, but would limit effectiveness to the orbits that MUST be very specific to work. For most satellites this doesn't matter. If 500 km is clogged, you design your mission to work at 505 km. I could see something like this working for geostationary orbits and sun-synchronous orbits as they require specific altitudes and inclinations, but not for much else.

Except orbits are neither that precise nor that static, without active control.

Look up the "Gabbard diagram" of any orbital collision. Some of the debris ends up in rather elliptical orbits, with an apogee considerably higher than the orbit of either object that went into the collision. That means it presents a risk to satellites even in higher orbits.

Also, orbits decay. The atmosphere doesn't just stop at a line; there's thinner and thinner wisps of gas out there, ever so slightly dragging on orbiting objects. So higher orbits slowly get lower, and lower orbits rapidly get lower still, until the orbit turns into an entry trajectory.

The properties of the exosphere are fickle and change rapidly, influenced by the solar wind and other forces. So while it's certain that orbiting objects experience drag, it's very uncertain how _much_ drag.

An object in an elliptical orbit spends some of its time with a very low perigee and thus a lot of atmospheric drag and thus its orbit changes rapidly in ways that're hard to predict, even if its apogee is high enough that it also crosses orbits of interesting things that're trying to avoid it. And the less predictable it is, the harder it is to avoid.

An incentive appears to exist to wait for collisions every once in a while so that there's more junk at different levels to clean up, and to prove the need for cleaning up junk.

1) Be Space debris company

2) Setup shadow satellite corporation

3) Satellite corp launches satellite to valuable orbit, and intentionally separates into 2-3 easily caught pieces. "Oops! Our satellite failed"

4) space debris company cleans up the orbit quickly and easily, receives bounty from government agency

5) Profit

A little far-fetched maybe, but there's a good sci-fi short story wrapped up in there.

Obviously the fix for this is to let the one that wants to have the satellite in that orbit pay for the cleaning of that orbit instead of some government.

I should still pre-emptively trash some valuable Sun-Synchronous orbits before anyone else launches. Incentive is still there!

Well, if we're imagining dystopian science-fiction stories in this vein, let's say that the salvage company automates their cleanup with an AI approximately as sophisticated as YouTube. Now every satellite launch is subject to malicious "take down" requests from competitors along with the whimsies of the algorithm.

6) Shadow satellite corporation contracted to destroy Beidu navigation system.

Someone is coding themselves a minivan I see.

Only because space debris are a negative externality at this time. If there was an (international) way to fine companies based on the trash they left in orbit, this would all be very straightforward.

There's thankfully a very obvious repercussion to leaving stuff in orbit that anyone planning to put something in orbit can see in obvious ways, unlike the delayed and hard to account for impact on the climate any one company will have.

This is completely off topic but what accent is the narrator speaking?

He pronounces "research" as "resorch"/"resauch", "greater" as "greator" etc. and in other regards it seems to flip between American to slightly British English.

Never heard this accent before.

It's an American accent, but with rhotacism, a type of speech impediment. He sounds vaguely British at times because of the tendency for "R" to come out sounding like "W"

https://en.wikipedia.org/wiki/Isaac_Arthur

Thanks a lot. I wasn't aware of this speech impediment and how it causes the vaguely British at times.

I actually have the same impediment but never knew the term `rhotacism` - thanks!

It's a speech impediment; he has trouble saying R's (and has improved as he's narrated more and more videos).

Isaac's earlier videos would show Elmer Fudd with the message "Having problems understanding me? Turn on CC." Example: https://youtu.be/gOu3zGfP-TQ?t=40

Source: I've watched lots of his videos and highly recommend them—mind expanding ideas!

Thanks a lot for the context. I have to say I didn't really have a hard time understanding him. I didn't even consider the possibility that it was a speech impediment.

American, but he has a speech impediment.

I was going to ask the same question, its so unusual but never heard it before

as a native english speaker I would guess dutch, norwegian, swedish or icelandic

Even if someone solves the technical part (cheap recovery), there are multiple practical problems with salvaging.

1. Satellites don't have much to salvage at EoL, they are typically obsolete at this point, at least for their main purpose. Their components degrade as well - space is a fairly aggressive environment and they aren't designed to be reusable.

2. They often contain highly regulated components that have tight export restrictions.

3. They might contain state or trade secrets and recovering by a third party is highly undesirable.

I think the thing you're salvaging is the orbital itself. That has value and the salvager should get a percentage of that. This requires international regulation we don't have though.

At least right now any particular "orbit space" does not have a meaningful value, as equivalent orbit spaces are available for free; while they aren't unlimited theoretically, they are essentially "first come first served" and there is no possible market for those spaces because current international treaties essentially permit any country to allow a launch in any free orbit and no country is permitted to make any exclusive claims to any parts of space that they are not actively using right now.

So even if some country e.g. USA would pass some laws allowing to reserve some spot in a with an option to resell it, that would only mean that USA would prohibit their own launches to that orbit, but any other country (China, France, Russia, etc) could still authorize anyone to launch to that orbit and once the orbit is taken it would be illegal for the USA buyer to launch there, and there would be no right to any compensation from whoever took that spot, because according to current international law there can be no exclusive right to that spot.

Given enough debris at different orbital heights, maybe Woz company can collect it at one location and use it as a launch platform, using the debris as the reaction-mass, then they can use solar power as the energy source to launch to higher orbits, rather than ejecting rocketfuel for thrust. Does this seem feasible? Given certain rocket trajectories, the debris could be made to fall back to earth, solving 2 problems at once - escape velocity energy needs as well as excessive space debris.

*Using space debris as railgun payload, but the railgun (rocket ship) is what you want to accelerate.

Key West fun fact, Florida’s first millionaire made his fortune as a wrecker https://en.m.wikipedia.org/wiki/William_J._Curry

Reminds me of Salvage 1 (https://en.wikipedia.org/wiki/Salvage_1), Andy Griffith goes to the moon in 1979!

Crazy idea: can new satellites be assembled from the parts of old ones: the parts are already in orbit, you can’t reuse chips, but you can reuse solar panels, wires, external walls, etc.

Crazy idea: can new boats be assembled from the wrecks of old boats: the parts are already in the ocean, you can't reuse metal, but you could reuse masts, wood, and hulls, etc.

The big difference is that it's very cheap to get something in the ocean, and quite expensive to get something up in orbit. For a mast on a boat, 99% of the cost is in the mast and 1% in getting it where it is; For a solar panel in orbit, the panel itself was cheap but the majority of cost was spent in pushing it to orbit.

So you are saying it’s possible?

Yea this thread hurts my brain, I legitimately can't tell.

But I believe it would be, Water World style. Why not re-purpose scrap parts, you could even make other helper robots with the scrap.

I'm reminded of Seveneves with the robots that make more robots tk make more and bigger robots. Man I'm gonna re-read that now.

Sorry my “so you are saying it was possible?” was supposed to just be a little joke to the guy talking about ships.

I think what you are describing might one day be possible, but it’s so far in the distant future that technology would have to move along way before we start to think of this outside of science fiction.

The level of processing and manufacture required to turn junk into a robot is huge, and would require a large facility on land. You would need to be able to melt and smelt metal, remove impurities, cast parts etc and doing all this in space with tiny robots rather than a floating mega-factory would require a level of technology that we don’t yet have.

Note that you can’t just reassemble parts because they won’t fit together unless they are all standardised, they could be damaged, and they likely suffer from metal fatigue and wear (eg to the boat point, this is why we make boats from fresh wood rather than reuse rotten wood from a shipwreck).

yeah, this thread "hurts my brain" because people aren't getting that my reply was sarcastic.

Good question—DARPA has asked it, too: https://arstechnica.com/science/2013/01/darpa-unveils-roboti...

Even if you assume there are sufficient working parts in orbit to construct working satellites, doing that reconstruction in space would require gathering them together in space either by people (super expensive) or by a sufficiently flexible robot, in which case we're already sending up something, just send up the desired new satellite instead.

Alternatively we could deorbit components without them burning up and assemble new ones down here, but that would also be vastly more expensive than just making new ones down here to begin with.

I've seen this kind of things in many works of science fiction, but it makes a lot of sense when you think about it even for non-space related salvage.

Thank you. I could not figure out the business proposition behind it from the release.

Orbital tolls :)