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Why We Don't Shoot Earth's Garbage into the Sun (2019)
- dTal 6y agoThis is like asking why we don't use the Large Hadron Collider to make toast, and then answering by going into detail about how tricky it would be to coax the LHC into making toast of acceptable quality. We don't do it because you don't use hyper-expensive mega-engineering to solve mundane problems with easy solutions, like "where do I put my banana peel".
- blablabla123 6y agoNot to mention radiation at LHC...
- t0ddbonzalez 6y agoHumanity in a nutshell: "Why change our polluting ways when we could just blast our junk into space?" Why do we think we have the right to blast our junk into space? Who does the cleanup when a rocket explodes after launch and covers Florida/Guyana/Khazakstan in used diapers and hypodermic needles?
- JoeAltmaier 6y agoToo late; already covered.
- t0ddbonzalez 6y agoReally? How so?
- JoeAltmaier 6y agoIsn't the whole issue, get the trash out of our ecosystem and put it 'into space'? That's the entire topic.
- cletus 6y agoWeird, I didn't find the term "delta-V" anywhere in the article. Most on HN probably know this but delta-V is the change in velocity required to reach some goal. Fun fact: it requires more delta-V to hit the Sun than it does to leave the Solar System. For giggles, here's a delta-V map of the Solar System [1]. Of course there's the issue of getting things off Earth to begin with but even if you take that as (economically) solvable the detla-V problem remains. Site note: there are lots of proposals for cheaper LEO solutions (in $/kg terms). Probably the most famous is the space elevator but that's actually a bad solution for many reasons and possibly not even feasible since we'd have to invent a material strong enough. What could well reduce that from $thousands/kg to <$10/kg is an orbital ring [2] (and check out the rest of his Uplift series if you're interested at the other options). The beauty of this is it doesn't require any magical material (cough graphene cough) and requires no new physics. It's largely just an engineering problem. Granted it's a massive engineering problem. To be fair, the article does mention how much energy you'd have to lose but it strikes me as just being so much easier to explain in delta-V terms. [1]: https://external-preview.redd.it/U5iH7huE5qKth7ZFvipXt8vzaFOO99qHFh9o9_SkLLk.png?auto=webp&s=d145ac9ae496abe35fae86fc11a584d62fe42592 https://external-preview.redd.it/U5iH7huE5qKth7ZFvipXt8vzaFO... [2]: https://www.youtube.com/watch?v=LMbI6sk-62E https://www.youtube.com/watch?v=LMbI6sk-62E
- twanvl 6y ago> Fun fact: it requires more delta-V to hit the Sun than it does to leave the Solar System. Isn't that the delta-v needed to reach a stable orbit? That is, to slow down and counteract all the kinetic energy you gained from the sun's gravity. To just hit the sun (with high velocity) you wouldn't need to do that.
- me_me_me 6y agoYes, moving towards sun/ any body that is inbeteen sun and earth you actually 'slowing down' (after reaching earth's orbit). When you reach zero V relative to sun you will just drop to its surface (same with any other planet). Anything on the outside you 'speedup'. That's why its called delta-V as its relative change in V needed to get somewhere. And its independent of size, type of craft etc.
- NikolaeVarius 6y agoTLDR: It takes a ton of fuel to slow down enough to get a payload to fall into the sun.
- deleted 6y ago[deleted]
- shadowgovt 6y agoIt is a grand feat of engineering to hit the sun on purpose.
- coldtea 6y agoIt would be burned to a crisp long before it reaches the sun, so that's a moot point. Doubly so since it's also extremely expensive to escape our orbit...
- dmurray 6y agoHow can this really be a question? It's obvious that it's expensive to launch things in rockets: that has very little to do with the orbital mechanics nerding out of "actually you can't just fall into the sun, you need a surprising amount of delta-v" and everything to do with the cost of building skyscraper-sized shiny single-use machines that are 90 parts fuel, 9 parts expensively machined metal, and 1 part "garbage" payload. In other words, launching garbage in any kind of rocket is incredibly inefficient compared to dumping it on the ground or into the ocean, so the consideration of "would it be cheaper to send it to the Sun or Jupiter" doesn't really come into question.
- coldcode 6y agoBut could we accelerate the payload using something other than a rocket? After all G-forces are not an issue for garbage. Assuming you could get to orbit, how much fuel would it take to get it going in the right direction and then have gravity do all the work?
- okl 6y agoYou would need a delta-v of roughly 30km/s to decelerate the garbage sufficiently to let gravity do the job.
- kalium-xyz 6y agoSadly its also a waste of garbage to throw it in the sun, we can burn it or recycle metals later
- coldtea 6y ago>But could we accelerate the payload using something other than a rocket? As in?
- throwaway744678 6y agoA giant slingshot?
- 6y ago
- 101404 6y agoBecause 1 kg to orbit costs 5000 USD.
- senectus1 6y agogoes down by quite a bit when /if we build a tether (space elevator). but would still be a stupid idea. everything is recyclable
- Aardwolf 6y agoIf it ever gets that far, I'd rather see it launched in an orbit around the sun than into the sun, the material could still be useful later
- jadell 6y agoIf we're saving it for later (but for some reason don't want it on Earth) we should just launch it into orbit around the Earth. Why waste the fuel to send it outside Earth orbit just to need it back later. Even if we wanted to use the materials somewhere else in the solar system, just park it in orbit around Earth until its time to move it.
- Aardwolf 6y agoPossibly to avoid this Futurama scenario: https://en.wikipedia.org/wiki/A_Big_Piece_of_Garbage https://en.wikipedia.org/wiki/A_Big_Piece_of_Garbage
- amelius 6y agoIf only we could shoot all those rocket exhaust fumes into the Sun.
- alexandernst 6y agoThere might be a slightly modified version of this question which might actually make sense: "Why we don't shoot nuclear waste into the Sun". Surely, the cost of storing that type of waste here (on Earth) is very expensive, both from economical perspective and from risk management perspective. It could be very interesting to compare the costs of sending 1kg of nuclear waste into the sun (or out of our solar system, if that makes it cheaper) compared to storing 1kg of nuclear waste anywhere here on Earth, + adding the cost of the infrastructure that is required to actually store and preserve that waste, + adding the cost of people that are required to protect that infrastructure (a facility of some sort), etc...
- dariusj18 6y agoBecause a catastrophic failure of a launch would be very bad.
- 08-15 6y agoNo infrastructure or crew is required to "protect" the "infrastructure" around a glass log on the ocean floor for the ~500 years it takes it to become as radioactive as natural uranium ore. Why don't we discuss this easy disposal option seriously? Why do we instead ask seriously about launching it into the sun instead? Because nuclear waste has been politicized to such an extent that most people have no idea what it is composed of, what the halflifes of its constituents are, how radioactive it is, how chemically reactive it is or even what state of matter it is in. But everyone knows that, like, it is, like, totally dangerous!
- ragebol 6y agoEven if it would be cheap to launch junk into space, we'd still have to solve some of the same issues we'd have to solve now as well: collection. To put it on a rocket, you'd have to collect the junk first, which we currently don't do well (except in a couple of countries). Nuclear waste is well collected though, I'd say. Breaking that down to it's constituent protons and neutrons would make it harmless right? Though I have no idea how much energy that would cost, only that the lower bound is probably well above what is reasonable.
- atarian 6y agoEven if we had a cheap, reliable way of sending garbage to the sun I am skeptical of the idea that the garbage would just magically disappear. It would probably accumulate into another problem later down the road.
- TheSmiddy 6y agoExactly, our garbage is made up of the most valuable elements on earth, as proven by the fact that they were used to make useful products, eventually we will be mining garbage to extract the value once the cost is cheaper than traditional mining. If we launch it into the sun eventually there will be a resource shortage of some kind.
- JoeAltmaier 6y agoCheaper in energy to burn it or bury it, than to put it into orbit, and then accelerate it enough to fall into the sun. Yes, accelerate.
- 2OEH8eoCRo0 6y agoSimple. The goal is to get rid of trash. This accomplishes the goal but others ways accomplish the same goal at much lower expense.
- bobwernstein 6y agowhy don't we build a chimney up to space and release all that co2 into space?
- JoeAltmaier 6y agoNot as silly an idea as it might seem. Even releasing it into the upper atmosphere (a few miles up) would make a difference.
- guiltygods 6y agoOne alternative could be instead of shooting surface based garbage into the Sun can we not not just sequester the thousands of dead/decommissioned/dangerous human launched objects orbiting around our planet and launch them towards Sun?