Hacker News Reader

Comment by netzone | Hacker News Reader

What would the effects be of releasing nuclear waste in space? Could we sent up all of our nuclear waste, put a rocket on it and just let it disappear into the distance?

View on HN

I think the drawback for space disposal is the risk of rocket failure. If a rocket explodes with nuclear waste on board, the waste would spread over a large area. It's safer at the moment to consolidate nuclear waste in small areas away from civilization.

>If a rocket explodes with nuclear waste on board, the waste would spread over a large area.

Space is very big. Is it actually likely that said waste spreading would even be noticeable?

When a rocket explodes, it's normally in the atmosphere right over an ocean.

I misunderstood what you were saying than, I thought you meant the rocket was exploding when it was already far into space away from Earth.

If it blows up 500m above the launch pad you aren't in space.

Think what the argument against it is that the rocket explodes during launch, before actually leaving earth behind. Then it would most probably be noticeable.

In the 1950s they thought that Nevada was very big and that the waste wouldn't even be noticeable.

They also thought the Pacific Ocean was very big and that the waste wouldn't even be noticeable.

Car drivers still think this way with their toxic emissions. It is very human to think 'out of sight out of mind' rather than 'take only photos, leave only footprints', so maybe it is actually fine to trash space with waste.

This... isn't really relevant for space. The amount of emptiness so massively outweighs the quantity of matter and energy it would be literally impossible to utilize a nontrivial portion of the volume available.

The only case in which releasing waste into space is problematic is when it's within a highly-utilized area, for example LEO. In the future, we may potentially use various transfer orbits and/or the Interplanetary Transport Network [1], so we should presumably avoid dumping there, but even within the solar system, the sheer volume of vacuum dwarfs any possible use.

[1] https://en.wikipedia.org/wiki/Interplanetary_Transport_Netwo...

"All told, the nuclear reactors in the U.S. produce more than 2,000 metric tons of radioactive waste a year..." (https://www.scientificamerican.com/article/nuclear-waste-let...)

Let's call it $20,000 / lb to orbit (http://www.businessinsider.com/spacex-rocket-cargo-price-by-...) and say double that for the "disappear into the distance" part.

That gives us $160B to loft the US's nuclear waste for one year into not-my-problem-ness.

That doesn't sound unreasonable, right?

P.S. Don't drop it.

>Don't drop it

Is the unreasonable portion, not the cost.

Why would we do that? Nearly all of that so-called waste is recyclable for more energy than we got out of it the first time.

There is risk, but by coal is even more dangerous. The risks are all easy to mitigate if you use modern engineering.

You would need a huge fleet of huge rockets to do that. Of the order of 50 Saturn V - sized rockets per year just to keep up with the current production of nuclear waste. And about 1000 of them to get rid of what we accumulated so far. Only 13 Saturn V’s have ever been launched.

The cheapest choice would be the falcon block 5. Gooooo spacex.

NASA and the DOE did a study on this and they determined that it was too expensive to do it, though safe enough but that we might want the waste later. Vitrification and storage was deemed cheaper, safer and more 'reversible'.

I thought everything, including our bodies were made up of nuclear waste from stars.

Note that you'd want to go beyond the escape velocity or you'll just put it in some orbit. I'm not sure how practical that is, keeping in mind costs.

How about just sending it to the moon instead? Perhaps then we could use the moon as a giant space ship by blowing up the nuclear waste?

It's a fascinating idea from science fiction perspective, but moving the Moon anywhere will probably have devastating effects on the Earth's biosphere

I think that's just short term thinking: When the sun expands into a red giant, the gas drag will slow down the moon. I think that means it will crash into the earth if it's not removed before.

Regardless of whether or not what you say is likely to happen (I think not, but anyways), if humans can even last long enough to see the Sun as a red giant, we'll have larger problems on our hands. In any case, we'll likely have destroyed ourselves or evolved into something else by that time.

The Moon orbits the Sun, and is only mildly perturbed by the Earth. Gas drag would decay the Moon's orbit, but it's not at all clear to me it would crash into the Earth. It seems far more likely it would simply fall into the Sun.

The Earth and Moon system orbit the Sun, but the Moon is very much in orbit around the Earth.

A more likely scenario is that the Earth's orbit will move outwards as the Sun expands, since stars in the red giant phase(s) lose a lot of mass. It's plausible that the Earth/Moon will not be destroyed, physically. But in that case all life would have been obliterated due to the immense temperatures associated with having the surface of the Sun within a few million miles (or less) of Earth.

Long term thinking is not useful when long term means "5 billion years".

p.s. The process is shown in this documentary: https://www.youtube.com/watch?v=HE06rNkxlks&feature=youtu.be...

Thanks!

Alexander Abian, is that you?

(https://en.wikipedia.org/wiki/Alexander_Abian)

Maybe he has watched too much "Space 1999"? https://en.wikipedia.org/wiki/Space:_1999

Nuclear waste is just that - waste. It's generally no longer capable of supercriticality.

Nuclear explosions as a method of space propulsion is a viable idea [1], however. (Using the Moon would be rather inefficient though.)

[1] https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propuls...

Reply on news.ycombinator.com