51–60 of 116 posts
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Has anyone studied these protesters? My off-the-cuff sense is they’re mostly older environmentalists.
It's because sometimes a rocket explodes on the launch pad or a few seconds later, and it could spread radiactive material over a very wide area.
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they should be indoctrinating kids at school that nuclear is safe, rather than other "stuff" they tell them nowadays
Totally. You're probably catching downvotes from people offended by "indoctrination", but a) indoctrination is what schools do, that's their purpose, and b) nuclear is actually pretty safe. I agree with the sentiment. Anti-science sentiments proliferate partly because science doesn't spend much on public outreach, especially compared to people who want to make a buck off scaring others about new technologies. NASA ha…
Nuclear energy may be safe, if done under near-perfect condition, with extremely large budgets to understand risks, and plans to mitigate incidents. There is truth to the argument that nuclear power saves lives compared to coal power.
But nuclear power isn't inherently safe. It is, by its very nature, extremely dangerous. Actual nuclear scientists understand that. See, for example, Feynman's work on nuclear safety during the Manhattan project.
Strapping a nuclear reactor to a rocket is almost by definition a dirty bomb. Depending on the height and mode of an eventual launch failure, the result could be anything from Tchernobyl to a less-dramatic yet more deadly dispersal of nuclear material in the upper atmosphere.
The dose-response relationship of radiation exposure is largely linear, meaning the latter event might just increase your risk of brain cancer by 0.005%. Yes, you may consider it negligible. But statistically, it would kill half a million people.
To blithely state that "nuclear is safe, hoho, why shouldn't we strap Plutonium to a rocket, you environmental nincompoops" has nothing to do with science, and gives science a bad name. Maybe NASA could come up with a way to protect a reactor during a missile launch. But it wouldn't be easy, and saying "why wouldn't we?" on TV would not inspire confidence in their abilities, but doubts in their sanity. The right thing to say on TV is "We're sending a reactor into space, and here are the mechanisms we've come up with to make it safe..."
My first thought was "deep space mission". But because of moving parts involved, this is probably not the use-case. So a bit OT, I was wondering if anyone has yet thought about the solution of still using solar panels for them, but to also use a mirror to focus more light in the direction of the probe or a laserbeam? I mean, theoretical I don't see why not, appart from being more expensive? Andd you could also offset…
Inverse square law. Every n AU you go out from the earth you will need n 2 are of mirror to focus on a solar panel to get the same power. That assumes you can even build a structure that can keep that shape. Say you have a mission to Uranus, you will need a mirror with 400 times the area of the solar cells to get as much power as they would in earth orbit.
But if you use a laser?
I imagine it will be easier to focus it more precisely?
My first thought was "deep space mission". But because of moving parts involved, this is probably not the use-case. So a bit OT, I was wondering if anyone has yet thought about the solution of still using solar panels for them, but to also use a mirror to focus more light in the direction of the probe or a laserbeam? I mean, theoretical I don't see why not, appart from being more expensive? Andd you could also offset…
Inverse square law. Every n AU you go out from the earth you will need n 2 are of mirror to focus on a solar panel to get the same power. That assumes you can even build a structure that can keep that shape. Say you have a mission to Uranus, you will need a mirror with 400 times the area of the solar cells to get as much power as they would in earth orbit.
Dibs on Solar Harvester
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Totally. You're probably catching downvotes from people offended by "indoctrination", but a) indoctrination is what schools do, that's their purpose, and b) nuclear is actually pretty safe. I agree with the sentiment. Anti-science sentiments proliferate partly because science doesn't spend much on public outreach, especially compared to people who want to make a buck off scaring others about new technologies. NASA ha…
In your zeal to defend nuclear energy, you're come around full circle, defending something indefensible, with arguments far removed from actual science. Nuclear energy may be safe, if done under near-perfect condition, with extremely large budgets to understand risks, and plans to mitigate incidents. There is truth to the argument that nuclear power saves lives compared to coal power. But nuclear power isn't inherent…
The thing about this reactor is that it doesn't work until you switch it on - so in case of an explosion you are spreading a near-stable isotope that you could handle without any health risks. Chernobyl doesn't compare, because the ashes were spreading isotopes produced as a result of operating the reactor, and are simply not present here until the reactor is actually switched on.
put it in a car
Earlier quoted context omitted.
Totally. You're probably catching downvotes from people offended by "indoctrination", but a) indoctrination is what schools do, that's their purpose, and b) nuclear is actually pretty safe. I agree with the sentiment. Anti-science sentiments proliferate partly because science doesn't spend much on public outreach, especially compared to people who want to make a buck off scaring others about new technologies. NASA ha…
In your zeal to defend nuclear energy, you're come around full circle, defending something indefensible, with arguments far removed from actual science. Nuclear energy may be safe, if done under near-perfect condition, with extremely large budgets to understand risks, and plans to mitigate incidents. There is truth to the argument that nuclear power saves lives compared to coal power. But nuclear power isn't inherent…
Earlier quoted context omitted.
Inverse square law. Every n AU you go out from the earth you will need n 2 are of mirror to focus on a solar panel to get the same power. That assumes you can even build a structure that can keep that shape. Say you have a mission to Uranus, you will need a mirror with 400 times the area of the solar cells to get as much power as they would in earth orbit.
Hm, ok the mirror is probably out of the question then. But if you use a laser? I imagine it will be easier to focus it more precisely?
Earlier quoted context omitted.
Totally. You're probably catching downvotes from people offended by "indoctrination", but a) indoctrination is what schools do, that's their purpose, and b) nuclear is actually pretty safe. I agree with the sentiment. Anti-science sentiments proliferate partly because science doesn't spend much on public outreach, especially compared to people who want to make a buck off scaring others about new technologies. NASA ha…
In your zeal to defend nuclear energy, you're come around full circle, defending something indefensible, with arguments far removed from actual science. Nuclear energy may be safe, if done under near-perfect condition, with extremely large budgets to understand risks, and plans to mitigate incidents. There is truth to the argument that nuclear power saves lives compared to coal power. But nuclear power isn't inherent…
But maybe I should have stated my main assumption explicitly: people at NASA know what they're doing. They're not incompetent morons, they can do the math. They already have absurd amounts of procedures in place to ensure a launch failure doesn't hurt anyone. They're not just trying to strap a bunch of random nuclear isotopes on a rocket and hope for the best.
> Strapping a nuclear reactor to a rocket is almost by definition a dirty bomb.
No, it isn't. A dirty bomb is meant to create a large-scale radioactive contamination that's dangerous to humans, and U-235 is probably the last thing you'd like to put in it. It's an alpha emitter with a half-life so long it doesn't matter, so the only effect you'd get is heavy metal poisoning.
(That's beyond the fact that dirty bombs are speculative devices, and from what I read, they actually turned out not to be a real issue in practice.)
> Depending on the height and mode of an eventual launch failure, the result could be anything from Tchernobyl to a less-dramatic yet more deadly dispersal of nuclear material in the upper atmosphere.
That's the kind of thinking that I suggest we need to fight with a serious public outreach effort. Chernobyl was a total clusterfuck, but the only connection between it and the NASA project is the word "nuclear" in newspaper headlines. Chernobyl was an active reactor, and its explosion contaminated the area with reaction products that had very low half-life and underwent beta and gamma decay, making them really dangerous, unlike plain U-235.
> To blithely state that "nuclear is safe, hoho, why shouldn't we strap Plutonium to a rocket, you environmental nincompoops" has nothing to do with science, and gives science a bad name.
I'm not saying that. I'm saying that there's so much baseless fear around nuclear energy as a whole, that it's high time we stopped treating it as reasonable. And right now, the biggest danger around nuclear energy is the cost in lives of it not being used instead of fossil fuels.
Earlier quoted context omitted.
Inverse square law. Every n AU you go out from the earth you will need n 2 are of mirror to focus on a solar panel to get the same power. That assumes you can even build a structure that can keep that shape. Say you have a mission to Uranus, you will need a mirror with 400 times the area of the solar cells to get as much power as they would in earth orbit.
Does this mean that if you go towards the sun, you would be able to generate more solar electricity with less surface area? I'm not thinking dyson sphere style, but perhaps some sort of electricity space-tanker, that sails toward (or around?) the sun, collecting solar energy, and then returns to earth with batteries packed to the brim with energy? Dibs on Solar Harvester
The space electricity tanker idea is theoretically possible, but might not make any economical sense. For it to be worth it, it would have to store a lot of energy, so that it could ship back more than the cost of moving it around, while also being competitive with simply building more bigger collectors further away (and closer to the industry). But maybe a highly eccentric orbit, with a very low perihelion, would work.
Not totally sure if the math works out on this, but I could see moving the energy-intensive industry closer to the Sun, and having it use beamed energy to move resources and products to itself and back.