Nuclear reactor is an easy way out of a problem that has alternative solutions. Restriction on using nuclear power for previous missions did a lot of good in terms of researching and perfecting the alternatives (solar arrays).
Restricting the use of nuclear power does not prevent missions, it only adds to the cost of the mission, which is not really a technical problem.
Maybe launching one, fresh, yet inert reactor, is not a big issue. The issue starts when we fly a lot of them and they start falling back to Earth after some service time.
It is relatively easy to build safe reactors on Earth (if only everybody was interested in safety and not their own agenda). It is much more difficult when you are going to shoot the entire device into space and you can't have 1000:1 of shields and casings.
There is essentially no actual ecological or serious fear about these devices. The weapons ban was meant to help avoid nuclear exchange between nations; there's very little scientific data that shows there's added cost or risk of thousands of reactors falling to Earth and causing radiation poisoning.
Nuclear is exceptionally safe and all the recent accidents (and ones in the past, really) are all due to human stupidity and bypassing several failsafes. You can argue that's an issue that will never go away, and that's true in the absolute sense, but it's not a nuclear problem. It's a human issue. We're holding ourselves back for scientific research because of arbitrary issues; and the weapons test ban didn't even solve nuclear proliferation anyway.
Solar won't be held back because nuclear is finally an option. They serve two different purposes entirely.
Which could be applied to any challenge that humanity face. This basic human weaknesses is always what holds us back in any endeavour. It is dangerous to just dismiss it as "arbitary". You have to deal with these issues if you want to make big projects achieve their objectives.
Yes, I agree. People are often nonchalant about those low probability dangers. But a single death from Cancer is just as bad as the death of an astronaut, perhaps worse as they have not consented to the risk or understand it. We should care about that, especially as space exploration is such an optional undertaking which people don't have to support. That is why there is a range safety system and why anything radioactive needs to be treated with caution.
Hi, just to point out a hole in your reasoning, if these reactors are so safe then why even a small portion of the radioactivity escaping the containment shell can cause such a big disaster like Fukushima or Chernobyl?
Now, I understand there are differences in size and the level of radioactivity used (they won't be driven as close to prompt criticality as the power reactors) and they may be designed to be less reliant on active protection (pushing a lot of water as required means to prevent disaster).
But still, this is radioactive material in Earth orbit where stuff tends to fall back after some time and we don't always control when and where it reaches us.
> small portion of the radioactivity escaping the containment shell
The Chernobyl reactor was very unsafe by modern standards, it did not have a containment vessel and tens of tons of reactor material was blown into the air, not a small amount.
To actually blow the Chernobyl reactor, the personnel explicitly disabled quite a few safety systems that otherwise would not allow for a runaway reaction which led to a mighty (thermal and chemical) explosion.
Modern nuclear power plants are relatively safe. However, there is not enough data to determine how safe nuclear power is in general, because you have to take into account the whole production cycle including all long-term storage of nuclear waste.
Half life time of nuclear waste ranges from 30 years to 24,000 years, so it's possible that hundreds of people die in 30,000 years from now by being exposed to nuclear waste from our time.
I completely agree and don't think coal is better than nuclear power at all. Reduction of energy waste, renewable energy sources and nuclear fushion are the obvious way to go, but it may make sense to temporarily accompany them with nuclear power.
Sure, I didn't mean to imply that. I just meant that whatever long term damages are done need to be put on a timescale that actually helps us compare alternatives.
If hundreds of billions of lives are saved in the time it takes for nuclear to do real damage, maybe that's just worth it.
It is also worth to estimate how quickly nuclear production can scale up and deplace coal. I personally think wind and solar can scale up much faster economically and socially and more easily deplace coal and gas than nuclear could in the best case.
I'm not sure I am convinced by this argument. You say it "only adds to the cost of the mission" as if that wasn't an issue, but unfortunately our resources are finite. If we increase the cost of any given mission that means we cannot do other missions. There is always a trade-off here, and I am not sure if the advantages of solar would be worth the cost of holding back research that much.
You could easily make the opposite argument - solar power is an easy way out of making nuclear power safe enough to go up into space. Having to use nuclear power for missions might do a lot of good in terms of researching and perfecting safe nuclear power.
Nuclear reactors that have some service time on them are very, very, very radioactive. Just look what happens when a very small portion of that radioactivity finds itself into the atmosphere or water (Chernobyl, Fukushima, etc.)
It is maybe not as big a problem if we never plan it to return to Earth or Mars orbit (reactor is not as radioactive until it actually is started), but if we are using it to supply energy to the crew for the duration of the mission in deep space, the reactor will inevitably be radiactive and brought at least to Mars orbit or even back to Earth orbit.
Now, if that piece of junk falls to Earth, we have a big problem. Not the same kind of problem as falling solar array.
Not even Chernobyl, that had an atmospheric nuclear fire, the worst case scenario imaginable, had a economic, environmental or human live cost comparable to the impact of a single coal power plant.
It really concerns me when people on this forum, that has no excuse to not know better, parrots this anti-nuclear FUD.
Chernobyl had far worse consequences than you are indicating, even taking into account a coals plant's lifetime impact from mining to air pollution.
Aside from the headline numbers of 31 dead and 237 with acute radiation poisoning other costs include:
- Encasing the site in a sarcophagus that will need to be maintained essentially forever. Immediate disaster response was estimated at $18B in today's dollars.
- A 30km exclusion zone from which 135,000 people were evacuated. Costs from this include costs of resettlement, loss of essentially all capital, cropland, and infrastructure in the zone
- Outside the zone millions of tons of contaminated earth were trucked for containment. Remediation is ongoing to this day and will continue indefinitely. Certain agricultural production is limited by type and practice to reduce probability of contamination from deeper in the soil.
- Health monitoring response across Europe in the aftermath, plus increased monitoring forever in the neighboring countries
- An unknown number of additional cancers and birth defects
There are additional costs, mostly more evacuees than were likely strictly necessary and compensation to others affected. Its unclear how much of this are legitimate costs or not, but its worth noting that uncertainty and lack of transparency themselves have costs.
Chernobyl still is a massive cost factor for plenty of countries ( all that are helping out financially with building the new mantle ).
Also look at the large effects of Fukushima.
Every time nuclear power comes up here on HN, there are some fierce defenders.
No matter how 'safe' newer generation plants are and how much it was the oprators fault, the potential for disaster is there. And that's not even mentioning the high lifetime cost when you consider safely storing the material, which often falls to the public.
> Every ounce of nuclear waste is entirely contained, every other power source's waste is dumped into the environment.
That's a little disingenuous, though, isn't it? It's only contained because no one will allow it to be dumped ("stored") near them. Actually, the fact that we have to take special precautions with nuclear waste due to its toxicity is a disadvantage of nuclear power vs. fossil fuels (for example).
Obviously, there is a much different calculus when thinking about Mars though.
Costs for decomissioning a nuclear power plant in the US: up to 500mil (https://www.nrc.gov/reading-rm/basic-ref/students/decommissi...) (which needs total cost and revenue to put it in perspective, but it gives a sense of the scale and difficulty of decommissioning and storage.
It has everything to do with the economic costs. There is no other reason other than perceived threat to human life that drives that cost. How is that not obvious ?
That paper, and others like it, demonstrates that radiation is much more benign than generally believed, and that level of resources spent on threads that don't exists, especially in comparison with others, like drink a can of soda a day, or living in a city, is not justifiable.
The use of nuclear power should be encouraged and popularised whenever we can. Years of nuclear FUD needs to be unwound and humanity re-educated on the benefits of nuclear power. So much of our current climate change predicament could have been avoided. Its a crying shame.
What power source do you propose for a long-duration human mission to Mars, if not nuclear? Solar won’t work, given the loss of output during a dust storm.
If I were on my way to Mars I wouldn't go without nuclear power. It is too far away to have an Amazon drone drop off a fresh batch of batteries or solar panels.
Nuclear reactor is an easy way out of a problem that has alternative solutions. Restriction on using nuclear power for previous missions did a lot of good in terms of researching and perfecting the alternatives (solar arrays).
Restricting the use of nuclear power does not prevent missions, it only adds to the cost of the mission, which is not really a technical problem.
Maybe launching one, fresh, yet inert reactor, is not a big issue. The issue starts when we fly a lot of them and they start falling back to Earth after some service time.
It is relatively easy to build safe reactors on Earth (if only everybody was interested in safety and not their own agenda). It is much more difficult when you are going to shoot the entire device into space and you can't have 1000:1 of shields and casings.