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Comment by Multicomp | Hacker News Reader

This is probably one of those hacker news comments where it sounds good for 1 second then when you stop to think about it it falls apart, bu here goes.

throw the waste in a bucket strong enough to survive hitting earth at terminal velocitty. place bucket in spacex falcon9 rocket. launch rocket into orbit with escape velocity. watch nuclear waste vanish into vacuum of space forever. if crash, collect bucket and restart with new rocket.

financially costly? yes. solves the 'what about in 5000 years when someone opens it or it leaks?' questions, yes.

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I'm torn on which one second response is best. Contenders are:

1. Reprocessing is a better technological solution.

2. That waste is much safer in it's current location in a dry cask in the back lot behind a power plant than it would be on even the safest rocket.

3. Even if we punt waste disposal or reprocessing to future generations, we are still better off stacking waste in dry casks in the back lot behind power plants than burning coal.

4. “Actually, giving up nuclear and politics on Earth and using said rockets to start building space habitat on L2, L4, L5, Moon surface and so on and do life and society and nuclear up there makes far more sense”

The standard answer is "there's too much of a risk that an explosion would spread nuclear waste through the atmosphere". These days I'm not sure if it's true -- we've learned a lot about building containers which are safe even during rapid unscheduled disassemblies, and used them e.g. when sending nuclear powered rovers to Mars -- but that's the usual concern.

I mean we’re wishing for a bucket that can survive terminal velocity impact with the earth and is yet light enough to ride a rocket, why not add to that wish that it could survive explosion from said rocket?

I think there’s a few orders of magnitude difference in the amount of radioactive material in an RTG in a probe bounds for Mars, and the total radioactive daughter particle output of a nuclear reactor.

Another crazy idea would be to put nuclear reactors themselves in orbit, and then beam the energy down to the surface. Space is already pretty thoroughly radioactive, so a meltdown goes from "ZOMG WE'RE GONNA GROW EXTRA ARMS AND DIE OF CANCER" to "meh, just another Tuesday".

But then you have nuclear-powered space lasers, which will scare people.

Yeah, but if people don't like it, what are they gonna do? Complain? That'll just draw the attention of the nuclear-powered space lasers :)

How does one efficiency “beam down” gigawatts of energy? Or at all?

Light. Focusing mirrors or lasers.

But as others have pointed out, why would you bother with building space based nuclear plants and then converting that energy to light when you could just use the sun?

Microwaves. Ground station has to be several square kilometers, but it's cheap and birds can fly through the beam without harm.

For economic reasons you pretty much have to use phased array transmitters, with a reference signal from the ground to make it coherent, so if the beam gets repointed it gets a lot more diffuse than that.

I've seen how this plays out in SimCity. No thank you!

I support nuclear but if you're beaming power from space, it might as well be from solar panels. In geostationary orbit you have power 24/7, with 5X more sunlight per day than panels on the ground. The only time your satellite goes into shadow is for a few minutes per day around the equinoxes, half an hour max. Capacity factor is still over 99%.

With geostationary? Don't they track a location on the earth? Is the satellite not in the earth's shadow at night?

Geostationary is super far out— you're effectively in constant sun:

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

Except, as the parent noted, very briefly during the equinoxes.

And even that seems "easy" to circumvent by having redundant satellites, such that during the equinoxes (equinoxen?) only a fraction of said satellites are shadowed out at once. Alternately, a massive battery or capacitor bank could give the receiver enough buffer to hold out through an equinox-induced shadowing.

Basically Gundam 00 haha. I was young when it aired, but it left a long lasting impression of what the future of space exploration might be like. Space elevators and massive solar arrays around the planet.

It’s not the worst idea, but we kind of need to get the whole orbital elevator but done first before the massive planet-spanning solar array.

Truth though: I think Gundam 00 showed a shockingly plausible future (sans mechas, most likely) for our planet if we do not get over our reliance on fossil fuels. Global conflict on a scale that makes WW2 look like child’s play is an inevitability if we cannot mitigate the environmental impact and eventual depletion of fossil fuels, and that includes support to help less developed nations move away from them.

It's too easy for space junk to destroy it, also a single point of failure or attack. It's a terrible solution as long as we remain a warlike species.

I hate to break it to you but most of our power stations are vulnerable to attack already. Certainly anything near the coast could be taken out by our major adversaries, even with conventional attack.

For a lot of plants, an anonymous cyberattack could probably do it. That'd be way worse than an attack to geostationary, which very few actors could manage, and probably nobody could pull off anonymously.

Space junk seems a more serious problem:

https://physicsworld.com/a/space-debris-threat-to-geosynchro...

I've seen various proposals to clean it up but it'd take some work.

We already have that nuclear reactor beaming energy down for us to collect.

It's just too bad the planet keeps getting in the way.

And sometimes the moon.

Interesting idea, but my next thought was "how are you going to cool that thing?!" :D

Not sure in which direction you're joking, but heat dissipation can actually be a difficult problem in space, at least as close to the sun as Earth is, while outside Earth's atmosphere. For example: https://science.nasa.gov/science-news/science-at-nasa/2001/a...

That's exactly what I meant. Running a nuclear fission reactor (along with the high power beams to Earth) in vacuum might prove... problematic.

Or it could blow away the Van Allen belts and fry everything else in orbit, then drop plutonium somewhere.

Ironically perhaps, the best reason not to do this is "It is extremely likely that, given sufficient time, we will either figure out a way to use the waste besides high-yield weapons or a cheaper way to dispose of the waste."

Earth is huge. At the rate reactors create waste, the amount of land consumed by storing it is staggeringly low (the higher risks are transportation, which unfortunately the rocket idea doesn't solve unless we build a dedicated rocket site next to each reactor). Low enough to justify the risk-over-time of securely sequestering it instead of throwing it away.

Nuclear waste is a lot more than spent fuel. It's water, piping, tubes, maintenance tools...basically anything that went through or was part of a reactor.

The fuel itself is just a small part of it.

There are a lot of schemes that will solve the factual problem.

But I think the real problem is emotional. People are afraid of mushroom clouds and mutants.

They don't say that because that's not how we're wired. We come up with better sounding arguments to believe. But what need to be solved is the emotional problem.

One hundred million years later, a tribe of evolved cats sees an asteroid streak through the sky...

Haha. I've often said cats would likely take over.

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