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.
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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.
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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.
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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.
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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.
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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.
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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. Then, 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.
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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.
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.
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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?
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. But you still gotta clean it up and make a rocket. I don’t think we have even launched a rocket that big or heavy ever. It may require multiple rockets. Planet Express barely was able to make it happen, and they are in the future, only needed to clean NYC, and is also from a cartoon.
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.
But does it matter what speed the garbage is going at when it hits the sun?
No, but it’s going too fast sideways. It would miss the sun. You need to slow it down by the same apeed that Earth is moving, stopping its sideways motion and letting it drop into the sun.
Edit: I like making diagrams. Red is the trajectory you’re expecting. Blue is the Earth’s motion, which adds to that red arrow. Purple is the resulting actual movement of the trash rocket.
But do you need to slow it down all the way? Can’t you just slow it down enough to get the ball in an elliptical orbit where the trash ball gets very close to the ball of plasma?
The problem is slowing it down to any speed that would end up with it dropping into the sun is going to take more effort and be more difficult than firing it out of the solar system. It isn’t practical.
Space is big. It’s so big that our tiny ape brains have a hard time conceiving of how big it is. The sun is actually (despite it’s size) a relatively small target and is very very far away. Now the more delta-V you burn to slow the trash down the smaller its orbit around the sun will be. But that orbit starts enormous. So to get that purple line near the sun you do need to slow down almost the whole way, just to get it close.
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
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.
LEELA Should we really be celebrating? I mean, what if the second garbage ball returns to Earth like the first one did? FRY Who cares? That won't be for hundreds of years. FARNSWORTH Exactly! It's none of our concern. FRY That's the 20th century spirit!
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: https://trinket.io/embed/glowscript/6642756b52?toggleCode=true&start=result
Nailed all the points.
putting anything on orbit costs A LOT, per kg. Not worth it
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.
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
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!
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 dump our garbage into active volcanoes though? (I’m imagining an assembly line to the fires of Mt. Doom)
Just dig a hole in a subduction zone and let tectonics reclaim the materials.
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.
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.
First steep, gather all the ocean’s trash.
Good luck with that !
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.
Well keep in mind that the sun is not a fireball, but everything is recyclable, so why 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: https://www.youtube.com/watch?v=Us2Z-WC9rao
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.
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 and we’ll be lucky if the fallout is restricted to a single continent.