While I know Scientific American is a fairly mainstream targeted and softer science publication, this
>And the problem is now poised to get much worse because of the rise of satellite “mega constellations” requiring thousands of spacecraft, such as SpaceX’s Starlink, a broadband Internet network.
really could have used a LOT more qualification particularly since it's become a major recent talking point. There is one ultimate sure-fire way to reduce space junk: launch stuff to very low orbits. There is still some atmosphere (varying with heating and other factors) up a long ways in "space", and it's only above 600km or so that orbital drag becomes negligible enough that lifetimes really stretch out. The ISS for example requires regular reboosts or it would decay back into the atmosphere.
SpaceX focusing on economics has made it feasible to start planning constellations of comm sats that are low and very low earth orbit, with the understanding that inherently their lifetimes will be measured in single digit years. But that's ok since they can be replaced so cheaply. This is much better, not worse. Even if they go offline or got hit, the debris would have a very restricted lifetime. The media should do a better job of conveying how cheaper $/kg to LEO opens up a lot of new possibilities in what regulations are feasible and how we think about the basics of satellite design. A simple "Mega constellation bad!" is all wrong, and that's not necessarily going to be intuitive to everyone.
Here's an awesome diagram of all tracked space debris from 1959 to 2021 showing the constant cleaning by drag happening at lower orbits. It's the higher ones we really need to care about.
>> launch stuff to very low orbits.
>>Even if they go offline or got hit, the debris would have a very restricted lifetime.
That approach can help, but the problem persists. Lower orbits are much smaller than higher orbits. Focusing megaconstellations into a narrow 100-110km band is asking for trouble. The kessler syndrome could occur in a very narrow band, quickly rendering even short-lived satellites uneconomical. The narrower the band of orbits, the more likely and more aggressive kessler becomes. It is one thing to loose a few sats every year, very much another to have your entire constellation wiped out every year.
Also, take out SpaceX from the name and add all the competitors (potentially lower quality) that are starting or about to get into the space and you can understand the concern.
edit: my concern is the long chain of the curve of low-orbit satellite companies as price continues to have downward pressure.
When these satellites burn up in the atmosphere, what happens to all the particles? Do we have lots of likely toxic material just constantly being burned and circulating around?
Strictly the low orbits of StarLink actually make it a sort of non-issue: there's PLENTY of atmospheric friction at the orbits used so re-entry is only a matter of time.
The bigger issue is higher orbits where orbital decay has far small perturbations to rely on. Those can be 10,000 year orbits which makes for a real problem.
I really wonder tho what this does to isolated tribes. To look up at an unchanging night sky, and on a regular basis new movement, new pinpoints of light. What does this do to the conception of The World ?
Wait, how does launching stuff to low orbits reduce space junk?
Edit: I think I now understand your comment. I mean sure it maybe adds less space junk than launching things into higher orbits, but it doesn't really reduce it, right?
Can you give a rough estimate of what fraction of space waste is due to differing orbits of satelites? Like very low vs low vs geostationary? I don't know the gradations between those either.
You seem to know a lot about this subject! Years ago, an acquaintance of mine told me of their idea to use railguns to remove space junk. Is this a remotely feasible solution?
SpaceX is planning to launch up to 42 000 satellites (there are about 3000 now). Cheaper $/kg leads to more space junk and higher risk of Kessler syndrome, that doesn't need any qualifications, I think. If something goes wrong the fact that the cloud of debris will be there for 10 years and not 100 years is not a huge consolation
All I had to do is play a little Kerbal Space Program to understand how difficult it would be to clean up space junk in orbit. Orbit isn't like some 3D grid where you stick a roomba up there, and have it go back and forth until you get everything. Even if you have the technology that lets you grab anything you encounter, you first have to reach something. And then burn some fuel to match its orbit. And then burn some fuel to get to the next thing. And then burn some fuel to match that thing's orbit (more than before because you are now carrying more mass around).
It might be better to keep everything up there. Assuming the junk is re-usable in some way: If one day, we do manage to build some kind of industry in orbit, it will need to consume raw materials, and having all this scrap in orbit already means you saved most of the energy cost it would have taken to get all that mass up there.
I believe I saw a Scott Manley video recently where he mentioned that he does consulting work for people, and one of his customers apparently doesn't know about KSP because he built their simulation in something like a day and they were astonished that he was done already.
Most of the SpaceX commentators use it too.
It's always cool to me when something meant as a toy gets used for real. Like city planners practicing in SimCity or more recently CitySkylines.
There's another game that I think really goes to show orbital mechanics in how a little for longer is better (in controlibility) than faster for shorter. It's one of those low action games, so if you're into FPS, probably not your cup of tea. There are a couple of levels specifically for the oribiting examples.
In theory you could do it without completely matching orbits to save a lot of fuel. Just getting a close slow encounter, grabbing it and letting your orbit just be whatever the new average of your velocities is. It'd require a stronger capture system perhaps depending on the mass of your capture vehicle, but it would save a lot of fuel.
Recycling what's up there might eventually be viable but for the start we'll be shipping up raw stocks. Recycling is probably about as difficult as refining from metal rich asteroids once you consider all the coatings and paints that are added to things and having to sort all the different metals, plastics, and what have you out.
The following is based on the assumption that more and more stuff is going into earth orbit over time.
As others have noted, putting satellites in lower orbits, below 500km or so, definitely helps with keeping things tidy.
Beyond that, robust regulation about ensuring that very little or no additional non-useful stuff is placed into orbit is also good. That is, require everything that isn't useful to deorbit right away or relatively quickly, and have the ability to deorbit at EOL.
What's beyond all that is the set of all things in orbits that aren't useful and that will naturally stay up there for a long time, in addition to any NEW stuff that's added, either by error or by accident. For example, a satellite in a 1000km orbit that has everything it needs to deorbit at the ends of its life, but fails to do so for whatever reason.
As others have noted, matching orbits is a lot harder than most people realize. Specifically, it's quite energy intensive.
At this point, basic physics tells us what we must do. In order to get long-lived, useless stuff out of orbit, we need to be able to send up specifically designed stuff, and a lot of it.
In summary: the most fundamental solution to this problem is to vastly decrease the price per kg to orbit. Regulation helps, but does nothing to clean up what's already there, and to resolve the unintended addition of new junk.
Summary to the summary: the newest crop of launch providers are aggressively working on this problem by aggressively pursuing reusability.
"Not going smoothly" is weird phrasing - it's not "going" at all. It's still in the technology development phase, and meanwhile there is still insufficient consensus that more dramatic action needs to be taken.
I know the article touches on these points, I am mostly just commenting on the strange headline.
Or manga, it's originally a manga series before the 26-episode anime adaptation.
The anime actually diverges from the manga in the latter section, because it was started before the series had ended (the manga finished serialisation in January 2004, the anime finished airing in February of the same year… and it was a 26ep full-season thing), so viewing both can be interesting in more ways than the usual watching of filler and interest in cross-media adaptation:
> While the manga deals more with existential themes, and humanity's relationship with space, the anime further expands the political elements of the story.
It might be silly that it wasn't until watching this anime (and the whole premise for WHY space junk removal was/is so dangerous as shown by the show) that I fully "understood" the problem with space junk. It was good show on it's own as well but it really made the "space junk" click for me.
Also Anime; the much looser Gundam anime (particularly Gundam 00) and James Bond films (was it at least two now?) made me think of using super solar collection weapons.
The 'weapon' would reflect sunlight and 'shave' against cross-sections of the edge of earth's orbital spheres. Solar sail like light pressure would slowly nudge objects to either slower, or more erratic orbits where they'd drag and get lower.
Netflix has the South Korean SF flick "Space Sweeper". Do read the serious article first. The film is for entertainment. Crossing Belter and cyberpunk aesthetics, mixing up human languages as you'd expect from the future, it's fun.
'Catching' a piece of space debris is really a 7-dimensional problem, isn't it?
You have to be in the right place at the right time (4), but if you have the wrong velocity (+3) you just end up causing the very problem you're trying to prevent.
Space Junk has been an issue for "rocket scientists" since the 1980s. The consensus even back than was that it's really not doable simply due to physics and the volume of "space" in orbit. The only viable strategy identified was to design launched objects to re-enter and burn up. But that was only started with DOD and NASA - nothing could be assured that the USSR/Russia or China would ever do the same. And the military always kept the option to put national defense ahead of this as well.
I always look in articles about space junk for any inkling of addressing the fundamental physics issues we identified back in the 1980s and I've yet to ever see those mentioned. It's always some shallowly thought-out, gee-whiz ideas by someone who's never actually worked in the field. Elon Musk-style.
I want to know the collective mass of this 'space junk'.
It is indeed unusable now, but it is a lot of highly refined matter that is already high in the earth's gravity well.
The question is whether whether enough of it exists that it could become useful, or even profitable, to reuse/recycle it.
Once you've gotten a herding satellite to rendezvous and dock/grab the junk, how much extra energy is needed to park it in a useful common orbital location for later reuse/recycling, vs making it new on the ground and lifting it out of the gravity well again?
Seems it could be a profitably exploitable resource, if the scale is right?
For all the people saying that there's no issue with thing in very low orbits, I'm going to suggest considering the following issues.
1. When that busy ~500km orbit has a collision, some pieces might be kicked up to higher orbits where they pose a risk to other satellites. There's also important things in lower orbits, like ISS.
2. Every satellite that falls back to earth from any orbital altitude has to pass through very low earth orbit.
Between 1 and 2, the debris is never going to be confined to low orbits where everything decays quickly.
"And the problem is now poised to get much worse because of the rise of satellite “mega constellations” requiring thousands of spacecraft, such as SpaceX’s Starlink..
..It takes an Iridium-Cosmos-type collision to get everyone’s attention. That’s what it boils down to.... And we’re overdue for something like that to happen."
Perhaps the former is gentler, more statistical an alternative to the latter. Everybody be so cataclysmic these days.
I'm confused by the photo. Newtonian impact depth says an impactor of equal density to the target will only penetrate to its own length. How come the aluminum ball clearly went way deeper than that?
Before we get so excited about those high tech huts everyone is sleeping in these days, we should work on the problems we have right here in our caves.
Will huts help us share our mammoth meat more peacefully? Will huts make Atkinson Clan stop beating up Montanas? Will huts make Montanas any less annoying?
Mark my words, sisters and brothers. These problems will go with us wherever we build huts. Until we learn to make Montanas less annoying and Atkinsons less murderous, I say we stay in these caves.
> and don't go spewing their shit all over the cosmos
Why? What's the downside to littering on some random asteroid? There's no ecosystem that would care – not even bacteria – nothing and nobody would mind if you drop a plastic bag on 423 Diotima. Take a step back and think about why pollution on Earth is bad, and you'll realize that "polluting" an asteroid isn't ethically wrong.
Of course, that only applies as long as those asteroids are utterly devoid of life. Once there's an ecosystem, polluting becomes ethically wrong again.
[+] [-] xoa|5 years ago|reply
>And the problem is now poised to get much worse because of the rise of satellite “mega constellations” requiring thousands of spacecraft, such as SpaceX’s Starlink, a broadband Internet network.
really could have used a LOT more qualification particularly since it's become a major recent talking point. There is one ultimate sure-fire way to reduce space junk: launch stuff to very low orbits. There is still some atmosphere (varying with heating and other factors) up a long ways in "space", and it's only above 600km or so that orbital drag becomes negligible enough that lifetimes really stretch out. The ISS for example requires regular reboosts or it would decay back into the atmosphere.
SpaceX focusing on economics has made it feasible to start planning constellations of comm sats that are low and very low earth orbit, with the understanding that inherently their lifetimes will be measured in single digit years. But that's ok since they can be replaced so cheaply. This is much better, not worse. Even if they go offline or got hit, the debris would have a very restricted lifetime. The media should do a better job of conveying how cheaper $/kg to LEO opens up a lot of new possibilities in what regulations are feasible and how we think about the basics of satellite design. A simple "Mega constellation bad!" is all wrong, and that's not necessarily going to be intuitive to everyone.
[+] [-] Gwypaas|5 years ago|reply
https://www.reddit.com/r/space/comments/ld4vlq/gabbard_diagr...
[+] [-] sandworm101|5 years ago|reply
That approach can help, but the problem persists. Lower orbits are much smaller than higher orbits. Focusing megaconstellations into a narrow 100-110km band is asking for trouble. The kessler syndrome could occur in a very narrow band, quickly rendering even short-lived satellites uneconomical. The narrower the band of orbits, the more likely and more aggressive kessler becomes. It is one thing to loose a few sats every year, very much another to have your entire constellation wiped out every year.
[+] [-] nabla9|5 years ago|reply
[+] [-] boringg|5 years ago|reply
edit: my concern is the long chain of the curve of low-orbit satellite companies as price continues to have downward pressure.
[+] [-] azinman2|5 years ago|reply
[+] [-] xyzzy21|5 years ago|reply
Strictly the low orbits of StarLink actually make it a sort of non-issue: there's PLENTY of atmospheric friction at the orbits used so re-entry is only a matter of time.
The bigger issue is higher orbits where orbital decay has far small perturbations to rely on. Those can be 10,000 year orbits which makes for a real problem.
[+] [-] euroderf|5 years ago|reply
[+] [-] phreeza|5 years ago|reply
Edit: I think I now understand your comment. I mean sure it maybe adds less space junk than launching things into higher orbits, but it doesn't really reduce it, right?
[+] [-] WhompingWindows|5 years ago|reply
[+] [-] vict7|5 years ago|reply
[+] [-] Hypocritelefty|5 years ago|reply
[deleted]
[+] [-] unknown|5 years ago|reply
[deleted]
[+] [-] SideburnsOfDoom|5 years ago|reply
Really? If there's a collision in LEO, doesn't debris spray in all directions, including some in the direction of higher, more stable orbits?
[+] [-] IlliOnato|5 years ago|reply
How big of a problem this can be is something to model and calculate, it's not something one figures out just from the general principles.
[+] [-] SavantIdiot|5 years ago|reply
Oh cool, let's shoot even more soon-to-obsolete pollution into the atmosphere. That's working so well on Earth. /s
[+] [-] yread|5 years ago|reply
[+] [-] ryandrake|5 years ago|reply
It might be better to keep everything up there. Assuming the junk is re-usable in some way: If one day, we do manage to build some kind of industry in orbit, it will need to consume raw materials, and having all this scrap in orbit already means you saved most of the energy cost it would have taken to get all that mass up there.
[+] [-] phreeza|5 years ago|reply
https://en.wikipedia.org/wiki/Laser_broom
[+] [-] hinkley|5 years ago|reply
Most of the SpaceX commentators use it too.
It's always cool to me when something meant as a toy gets used for real. Like city planners practicing in SimCity or more recently CitySkylines.
[+] [-] dylan604|5 years ago|reply
https://apps.apple.com/us/app/osmos-for-ipad/id379323382
[+] [-] rtkwe|5 years ago|reply
Recycling what's up there might eventually be viable but for the start we'll be shipping up raw stocks. Recycling is probably about as difficult as refining from metal rich asteroids once you consider all the coatings and paints that are added to things and having to sort all the different metals, plastics, and what have you out.
[+] [-] Diederich|5 years ago|reply
As others have noted, putting satellites in lower orbits, below 500km or so, definitely helps with keeping things tidy.
Beyond that, robust regulation about ensuring that very little or no additional non-useful stuff is placed into orbit is also good. That is, require everything that isn't useful to deorbit right away or relatively quickly, and have the ability to deorbit at EOL.
What's beyond all that is the set of all things in orbits that aren't useful and that will naturally stay up there for a long time, in addition to any NEW stuff that's added, either by error or by accident. For example, a satellite in a 1000km orbit that has everything it needs to deorbit at the ends of its life, but fails to do so for whatever reason.
As others have noted, matching orbits is a lot harder than most people realize. Specifically, it's quite energy intensive.
At this point, basic physics tells us what we must do. In order to get long-lived, useless stuff out of orbit, we need to be able to send up specifically designed stuff, and a lot of it.
In summary: the most fundamental solution to this problem is to vastly decrease the price per kg to orbit. Regulation helps, but does nothing to clean up what's already there, and to resolve the unintended addition of new junk.
Summary to the summary: the newest crop of launch providers are aggressively working on this problem by aggressively pursuing reusability.
[+] [-] visviva|5 years ago|reply
I know the article touches on these points, I am mostly just commenting on the strange headline.
[+] [-] tester89|5 years ago|reply
[+] [-] masklinn|5 years ago|reply
Or manga, it's originally a manga series before the 26-episode anime adaptation.
The anime actually diverges from the manga in the latter section, because it was started before the series had ended (the manga finished serialisation in January 2004, the anime finished airing in February of the same year… and it was a 26ep full-season thing), so viewing both can be interesting in more ways than the usual watching of filler and interest in cross-media adaptation:
> While the manga deals more with existential themes, and humanity's relationship with space, the anime further expands the political elements of the story.
[+] [-] joshstrange|5 years ago|reply
[+] [-] somedude895|5 years ago|reply
[+] [-] mjevans|5 years ago|reply
The 'weapon' would reflect sunlight and 'shave' against cross-sections of the edge of earth's orbital spheres. Solar sail like light pressure would slowly nudge objects to either slower, or more erratic orbits where they'd drag and get lower.
[+] [-] sand500|5 years ago|reply
[+] [-] errantspark|5 years ago|reply
[+] [-] aeroheim|5 years ago|reply
[+] [-] busterarm|5 years ago|reply
[+] [-] chr|5 years ago|reply
Warning, link autoplays with sound: https://www.imdb.com/video/vi1534902553?playlistId=tt1283876...
[+] [-] hinkley|5 years ago|reply
You have to be in the right place at the right time (4), but if you have the wrong velocity (+3) you just end up causing the very problem you're trying to prevent.
[+] [-] bilekas|5 years ago|reply
For some context of the amount of 'stuff' in space..
This does include debris also. It's a serious amount.
There is an incredible amount of Iridium from the mentioned collision :
http://stuffin.space/?search=1999-037
[+] [-] xyzzy21|5 years ago|reply
I always look in articles about space junk for any inkling of addressing the fundamental physics issues we identified back in the 1980s and I've yet to ever see those mentioned. It's always some shallowly thought-out, gee-whiz ideas by someone who's never actually worked in the field. Elon Musk-style.
[+] [-] toss1|5 years ago|reply
It is indeed unusable now, but it is a lot of highly refined matter that is already high in the earth's gravity well.
The question is whether whether enough of it exists that it could become useful, or even profitable, to reuse/recycle it.
Once you've gotten a herding satellite to rendezvous and dock/grab the junk, how much extra energy is needed to park it in a useful common orbital location for later reuse/recycling, vs making it new on the ground and lifting it out of the gravity well again?
Seems it could be a profitably exploitable resource, if the scale is right?
[+] [-] cratermoon|5 years ago|reply
1. When that busy ~500km orbit has a collision, some pieces might be kicked up to higher orbits where they pose a risk to other satellites. There's also important things in lower orbits, like ISS.
2. Every satellite that falls back to earth from any orbital altitude has to pass through very low earth orbit.
Between 1 and 2, the debris is never going to be confined to low orbits where everything decays quickly.
[+] [-] dalbasal|5 years ago|reply
..It takes an Iridium-Cosmos-type collision to get everyone’s attention. That’s what it boils down to.... And we’re overdue for something like that to happen."
Perhaps the former is gentler, more statistical an alternative to the latter. Everybody be so cataclysmic these days.
[+] [-] Causality1|5 years ago|reply
[+] [-] amelius|5 years ago|reply
[+] [-] beardyw|5 years ago|reply
[+] [-] aledalgrande|5 years ago|reply
[+] [-] readingnews|5 years ago|reply
[+] [-] fatiherikli|5 years ago|reply
[+] [-] mesofile|5 years ago|reply
[deleted]
[+] [-] dalbasal|5 years ago|reply
Will huts help us share our mammoth meat more peacefully? Will huts make Atkinson Clan stop beating up Montanas? Will huts make Montanas any less annoying?
Mark my words, sisters and brothers. These problems will go with us wherever we build huts. Until we learn to make Montanas less annoying and Atkinsons less murderous, I say we stay in these caves.
[+] [-] adwn|5 years ago|reply
Why? What's the downside to littering on some random asteroid? There's no ecosystem that would care – not even bacteria – nothing and nobody would mind if you drop a plastic bag on 423 Diotima. Take a step back and think about why pollution on Earth is bad, and you'll realize that "polluting" an asteroid isn't ethically wrong.
Of course, that only applies as long as those asteroids are utterly devoid of life. Once there's an ecosystem, polluting becomes ethically wrong again.
[+] [-] coldtea|5 years ago|reply