Submitted 3 weeks ago by TheImpressiveX@lemmy.ml to nostupidquestions@lemmy.world
I’m sure there’s a perfectly good reason why we haven’t done this yet. Too expensive? Would launching it into the sun cause the smoke (if there is even smoke in space) to find its way back to Earth, therefore polluting the air?
This is an incredibly stupid question.
Prohibitively expensive.
First the cleanup is gonna take forever and cost billions.
Then building a rocket is gonna be even more billions and time.
And then actually shooting something into the sun is harder than just blasting it out of the solar system.
You could save a bit by shooting it into another star, and not our own.
And then actually shooting something into the sun is harder than just blasting it out of the solar system.
Why is this true? Wouldn`t gravity do most of the work if we just kinda shove it in that direction?
Because if you launch something from Earth, you inherit the Earth’s orbital speed around the Sun. At that point, whatever you launched, will just continue to orbit the Sun. It takes less energy to accelerate to a solar system exit trajectory than it does to scrub off all of the excess velocity and end up on a trajectory that intersects the Sun.
Yes and no. The gravity of the sun will attract the rocket, but there are other things out in space besides the sun.
The problem then is other planets will start whipping the garbage rocket around who knows where. Could even come back around and smash into earth. Same problem with the sun, actually. It’s quite hard to hit something that’s that big when we’re this far away. If you miss even a fraction of a decimal of a degree, the trash rocket will swing around and you’re back to planetary hot potato.
It’s easier to sling the rocket past the south or north pole at a right angle to the solar plane. Up or down it’ll either keep going till it’s another suns problem or it joins the Oort cloud, which is kinda like a giant trash dump for everything that didn’t make it into our solar system when the sun formed.
The earth is traveling around the sun at about 67000mph (29,722 meters per second, the unit of measurement I’ll use from here on our for consistently) that means to fall into the sun (and this is once you’ve already expended a ton of Delta-V (delta-V being a count of meters per second in change to orbit your craft needs to make/can make) escaping the Earth’s gravitational influence) you’d have to slow down a significant portion (about 24,000 meters per second specifically) of that 29,722 meters per second that you’re hurtling through space at.
It takes so much energy to try to crash a craft into the sun it’s literally cheaper (only costing about 8,800 m/s of Delta-V, compared to about 24,000 m/s of Delta-V) to fly the craft very very far away, such as to the edge of the solar system, then zero out the angular velocity so it effectively falls into the sun, than it is to fly directly to the sun. This tactic also enables one to use another planets gravitational influence to “gravity turn” and save on fuel, but it’s still horrendously expensive to get even a small craft weighing a fraction of a ton from the surface of earth out to the edge of the solar system to begin with.
Rockets face a significant challenge in that in order to reach orbit they need a large amount of energy, sources from a large amount of fuel. To get 1 ton of payload to orbit it needs an amount of fuel which adds additional weight which then requires additional fuel to lift the mass of the fuel. Because of this it takes about 100kg of fuel to get 1kg to orbit
In short, I highly recommend spending a few days playing Kerbal Space Program to learn far more than will fit in a single comment about orbital dynamics. That game is amazing at teaching basic concepts of orbital dynamics and the incredible challenges space programs face in just getting payloads to orbit let alone incredible feats like interplanetary travel or interstellar travel
And then actually shooting something into the sun is harder than just blasting it out of the solar system.
This is fun to play with: trinket.io/embed/glowscript/6642756b52?toggleCode…
Nailed all the points.
Just gathering all the trash would be tricky (and, rocket aside, if we could do it easily, we’d probably have done it already; and just put it in a big garbage dump or something). Think about a swimming pool with a bunch of fallen leaves in it; it’s moving around constantly, and if you swim toward one it’ll kind of move away from you or break up when you try to pull it out.
Ok, let’s handwave getting the trash out of the ocean. It’s probably a solvable problem. First we need to sort it; all of the recyclables need to stay and be recycled, because we still need that material and because we need to reduce the weight. Compostable stuff can probably also just stay and be composted. Corrosive stuff probably shouldn’t go on a rocket. All of the wet trash (it came from the ocean, it’s all wet) needs to be dried out first; partially because we need the water, and partially because water is really heavy. And once we’ve done all of that…well, trying to figure out something productive to do with that big pile of dry trash is almost certainly going to be cheaper than launching it into space.
Ok, let’s handwave that problem too; let’s imagine we’re just going to grab it out of the water, compress it, and get it onto a rocket. Except we’re going to need a whole lot more than one rocket; a decent guess says that we’ve launched 18,003,266 kg into space ever—over our entire history in space—but the Pacific Garbage Patch alone is estimated to be at least 45,000,000 kg, meaning we’d need to launch more than twice the number of rockets we’ve ever launched before. More than 60,000 rockets have been launched since 1957, so that’s substantial. It would take a while; even if we turned the entire space industry’s output toward the project, they’re “only” launching about 1,000 rockets a year nowadays, so it’d take at least 120 years of NASA, SpaceX, Blue Origin, Roscosmos, the ESA, the Chinese Space Agency, etc. doing nothing but trash full-time.
Ok fine. Again, we’re handwaving; let’s imagine we have everything loaded up on rockets on the launch pad. Just getting it into orbit is tough for the simple reason that we have to take not just the payload (the trash) but also the fuel we need to get it there, and to get that fuel off the ground we need fuel, and to get that fuel off the ground, we need— you get the picture. The Tsiolkovsky equations govern how much, and thankfully the number isn’t exponential. But we will still need a lot of rocket fuel. Good thing we’re devoting the entire space industry’s output toward this for the next 120 years.
Now it’s all in space. Great! That was actually the easy part. We could just leave it in orbit around Earth; that would be a really really bad idea for a lot of reasons (but it’s what we’re already doing with our space junk, so…), and you said “into the sun,” so let’s talk about getting it there. Believe it or not, getting it into the sun is actually way harder than getting it out of the solar system entirely. If you were on a rocket, and you pointed it toward the sun, and you burned and burned and burned and burned until you ran out of fuel, you would counterintuitively end up somewhere out past the Earth’s orbit on the other side of the sun. This is because you have to actually cancel out your (very fast) orbital rotation, which you inherited from the Earth when you launched, before you can get pulled into the sun; otherwise you just end up going around the sun in a very elliptical orbit. It takes a lot of fuel to cancel out Earth’s substantial orbital rotation. So we have to get that up there too.
The good news is, once you get it to the sun, you’re good. It won’t cause any noticeable change to the sun (the entire Earth could fall into the sun and it wouldn’t care). And while the trash would initially melt and then burn due to all the heat, smoke is entirely a product of atmosphere and gravity; so no smoke would be generated and it would not make it back to Earth. But once all the ash made it to the sun, it wouldn’t continue burning per se; the sun doesn’t produce heat by burning, but by fusing lighter elements into heavier ones. The Garbage Patch is mostly plastic, so carbon polymers. But the sun isn’t big enough to fuse carbon into magnesium, which means all of those carbon atoms would just kinda…sink into the sun, hanging out under all the hydrogen and helium and lithium and beryllium and boron, but on top of the nitrogen and oxygen and such, for the next ten billion years until the sun turns into a red giant. At which point the sun will expand outward, potentially to engulf the Earth’s orbit; at which point it will reclaim all the atoms of the trash we didn’t send up there.
Eventually, after a bunch of different cycles and drama, the constituent atoms of our trash and everything else would become part of the white dwarf that our sun will become; a small, slowly-cooling stellar remnant. After that…we don’t know! The time it takes for a white dwarf to cool completely is longer than the life of the universe so far, so we have to speculate. It’s possible that the remnants of our sun and our trash and everything else might end up becoming a black dwarf, which might look like a shiny spherical mirror the size of the Earth.
All of that seems like a lot of work. I think we should try something else.
Just to add to this: rockets use a lot of fuel. And with “a lot” I mean that a rocket typically is 90% fuel, 7% rocket, 3% cargo (my numbers may be off a bit, but not by much). The further you want to go the more fuel you need, the heavier you get,the more fuel you need, and so on.
So to move out 100 tonnes of cargo, were going to waste, say 3000 tonnes of fuel, and that is just to get it into orbit. Getting enough speed to get it to the sun would probably literally require exponential amounts of extra fuel, which would require extra fuel rockets to come up, rockets just carrying “a little bit of” fuel for another rocket.
Then on going to the sun: the earth moves at about 30km/s around the sun. To cancel that out, you’d need a rocket capable of reaching 30km/s, which we currently -afaik- cannot. We can’t get rocket engines that can eject the burning gasses out at those soeeds, hence we can’t reach that speed, hence we can’t cancel out 30km/s. We’d need entirely new technology to be able to do that
To get into the sun, we’d probably want to fuel the rockets in space using reaction material mined in space (from the moon or an asteroid). That would more or less eliminate the problem you’re talking about, which is why I kind of skipped over that in my comment. But you’re right; this is one of a million things that makes space travel hard and expensive.
We can get up to any speed with enough time and fuel. The trash rockets would just need to get into a solar orbit, and then burn retrograde for a fairly long while. Or if you add a gravity assist in, this is doable today; the Parker Solar Probe got to (and indeed beyond) that speed, for instance. It’s easier and quicker when there aren’t squishy people aboard (we don’t tend to like acceleration much higher than 9.8m/s², for instance).
Oh, also: I don’t think it’s a stupid question. It’s a fun question. It might not be a workable plan, but I love thinking about this stuff.
Because incineration or proper disposal is not the problem. Gathering and segregation is. Plus, launching that sort of payload is going to be insanely costly.
The sheer volume is manageable as it currentlyis, but it’s spread out so much that collecting it properly is going to take a lot of time an effort.
The Great Pacific Garbage Patch is a bit of a misnomer, as it’s more of a vague area in which trash tends to collect. It’s not like an actual continuous patch that you can easily attack with a net.
Plus, launching that sort of payload is going to be insanely costly.
And causes its own additional air pollution as part of the launch.
It costs about $10,000 US to get a kilo of payload as far as Low Earth Orbit. I’m not sure this is going to scale up.
The short answer is just that doing so would be ridiculously difficult and expensive. Funnily enough, “launch it into the sun” is actually the easy part at this point. If we could collect all of the ocean’s trash, we probably would have done so and compressed it by now.
I love the optimism here, but unless there was a significant potential for profit, none of the people who have the resources to begin collecting ocean plastics could care less.
The sad truth is that the majority of the world’s resources are owned and controlled by a handful of psychopaths.
Launching stuff into the sun takes a shitton of delta-V. We should just launch it into the moon.
sun gets rid of it tho
But then all the fumes won’t just pollute the earth they will pollute the solar system, think of the animals on mercury, have a heart
I have a better idea! Launch it into a stable orbit in the oort cloud and maybe we can create a new planet there to colonize in a few centuries! It’s perfect because then we have the perfect place to send the radioactive soil from WWIII and a perfect base to hide from WWV from!
if I know my science fiction, it’s bound to get infested with nazis, dinosaurs, and bigfoots (bigfeet?) which might be worth it for the dinosaurs and bigfoots but I am sick to my ass of nazis.
Gathering all the trash to launch it into the sun isn’t easy, as many comments have pointed out. Not only do you have to counteract the velocity of Earth, but I’d expect you’d need a way to keep them alive on the trip there as well. I mean, I’m assuming you want them to be cognizant until the end, yeah?
I’m fairly certain there’s a Futurama episode on this topic
Yeah let’s make our trash New New York’s problem.
Or better yet, New New New York’s!
I think you wildly underestimate the amount of trash we’re be talking about here. This wouldn’t be a rocket, this would be thousands, or hundreds of thousands of rockets. And that’s just the start.
A rocket could lift 100-150 tonnes of trash. We have about 60 billion tonnes of trash.
So, um, 400M rockets.
Yeah, that ain’t happenin’.
Even if you could do this, it would be more effective to just do the “collect all the garbage” part and then store it in a heavily lined container forever.
putting anything on orbit costs A LOT, per kg. Not worth it
Just drill a hole to the core of the earth and dump it there. And you would just put a restart on all the materials.
So wait - why don’t we make an assembly line of trash into active volcanoes though?
Just dig a hole in a subdusctoon zone and let tectonics reclaim the materials.
Orbital mechanics makes launching stuff at the sun extremely difficult.
The earth has a gigantic a molten layer under our feet, and we couldn’t even dump it down there. Too expensive and difficult.
Long term, my guess is engineered super bacteria and/or robotics may clean up the trash in the future, if we don’t extinct ourselves first.
First steep, gather all the ocean’s trash.
Good luck with that !
And the one time the rocket goes kablooey on its way up, everyone down the flight path will get a shower of used hypodermic needles, disposable vapes, and old appliances.
You got it: it’s expensive/ “not financially viable,” so it won’t happen
There is “not financially viable” and than there is spending 12 times the gdp of earth each year.
Gathering is the hard part but I’m afraid just making raw ore and water into rockets and fuel would use more energy than what we are using today, just to offset the current waste output
It’s not too expensive.
The defense budget of the USA is 840 billion dollars. That’s not too expensive.
The reason it’s not being done is there’s no money to be made.
Profit first, survival of the species second.
Both can be true: it is too expensive, and there’s no money to be made. $840B wouldn’t put a dent in the launch costs for the tens of thousands of rockets we’d need to put into space over the next several decades in order to just get rid of the Pacific Garbage Patch, to say nothing of the rest of the trash on this planet.
And actually, there’s a third true thing: it wouldn’t help much. Having it on Earth isn’t the problem; it’s having it in the oceans that’s the problem. Partially because of the environmental impact, partially because of the biological impact, and partially because we don’t have access to it to reuse it, so we have to keep making more. Once we had it out of the oceans, we could recycle it or even just sequester it away.
I also have this incredibly stupid idea to build a very long pipe that goes all the way outside earth’s gravity pull, then launch all the garbage through it with a mechanism similar to a railgun. It doesn’t have to be thrown directly at the sun, just enough to launch stuff out of orbit.
There is no such thing as “outside earth’s gravity pull”. You can compensate with “centrifugal” force but you’ll need to position the point of mass in geostationary orbit and hang the rest of the structure off it (idea known as space elevator). However, there is no material whose tensile strength will support its own weight at this length. Steel cables max out at a few hundred meters at surface gravity.
i always say this about nuclear waste and usually i get punched in the face.
The problem with launching nuclear waste with a rocket is that you’re shooting an enormous dirty bomb and hoping it will make it out of the atmosphere. One single incident and we’ve got an environmental disaster of unprecedented scale.
Well keep in mind that the sun is not a fireball, but everything is recyclable, so would we want to do that?!
Weight savings to speed up the Earth and make it handle better in the corners so we can pass all these other loser planets
They touch on some relevant points of crossover in this interesting video: www.youtube.com/watch?v=Us2Z-WC9rao
mipadaitu@lemmy.world 3 weeks ago
First - The major problem with trash isn’t the getting rid of it part, it’s the gathering it up part. If we could do that, it wouldn’t be a problem.
Second - Launching things on a rocket is kinda dangerous still, there’s a risk the rocket will blow up on launch, scattering the material across a large area. This is a big reason why things like nuclear waste is a problem to transport in general, much less flying it somewhere.
Third - Launching something into the SUN is really hard, it would be easier to send something out of the solar system than back into the sun.
van.physics.illinois.edu/ask/listing/43694
Fourth - Someday we’ll figure out a use for everything, wall-e style. If we dump everything into a centralized landfill, we’ll eventually be able to collect/sort/recycle it into something useful. Throwing it into the sun (or off-planet) would make that stuff unavailable forever.
Finally - Throwing stuff into the sun would actually get rid of it forever, yes. It would be completely decomposed into the atoms it was made from. If we threw ENOUGH heavy metals into the sun, we could actually poison the sun making it not able to fuse hydrogen anymore, but even if we threw the entire earth into the sun, it wouldn’t be enough.
andrewta@lemmy.world 3 weeks ago
Another problem is that each item we throw into the Sun is comprised of atoms. We would literally be taking the atoms that makes up earth and throwing them away to a place where the atoms would no longer be part of earth. While a McDonalds cup isn’t going to catastrophically change earth, do it enough times and we could see a problem.
Doombot1@lemmy.one 3 weeks ago
What you also forgot to mention is just how much trash we generate… that would be a massive limiting factor as well. It’s hard enough to get a few tons of stuff on a rocket going to space. I couldn’t get an exact figure on a quick google search but humanity generates somewhere on the order of tens of thousands of metric tons of trash per day
themeatbridge@lemmy.world 3 weeks ago
The frustrating part is that this could be the easiest to solve. Require boats to weigh in and out, and account for everything on board. Minus fuel, plus fish, but those old, broken nets and plastic waste need to return to port to be properly disposed of. Throwing even a soda can overboard should result in significant fines.
xigoi@lemmy.sdf.org 3 weeks ago
How do you weigh a boat precisely enough to detect a soda can missing?
bestboyfriendintheworld@sh.itjust.works 3 weeks ago
A lot of ocean trash comes by river from poor countries.
MTK@lemmy.world 3 weeks ago
Also, sending things to space is way, way, way worse for our planet per kg of stuff, because of the fuel and parts that it takes
Vilian@lemmy.ca 3 weeks ago
How can earth have enough heavy metals for that?
mipadaitu@lemmy.world 3 weeks ago
You misread, I specifically said that Earth doesn’t have enough mass for that.