Nuclear Light bulb rocket "Liberty ship"

[Mr Skeptic]

People were pissed about Chernobyl because people died, and people were evacuated, hence the disaster got a lot of press. Nuclear testing released enough radiation that scientists can find a person's age from the change in radioactivity of their teeth (hint: many, many times more than any disaster). But there's very little outrage over that. The tests were done far enough away that no one died, and no one had to be evacuated.

 

Anyhow, nuclear powered rockets are not "big". Real men go for an Orion class ship (not the silly shuttle replacement, the original), which is fusion powered and could lift a city into space, and theoretically reach another star. But we don't have fusion power, you say? Never heard of an H-bomb, have you?

 

While you might question the cleverness of using insane amounts of money to build a rocket that uses about 1000 H bombs as propulsion, you can't question this: it would be really fing cool! Being able to lift 8,000,000 tons into space, you could put a city on it. It would also give new meaning to "eat my dust!"

 

Edit: facts about the Project Orion based upon 1950's technology

 

Actually, though, if the numbers in Moontanman's article are right, the nuclear lightbulb ship would actually outweigh a small Project Orion ship, and be much safer, as well as not leaking radioactive wastes into the atmosphere.

Edited October 3, 2008 by Mr Skeptic

[Moontanman]

I still think the issue is being reduced to unrealistic levels. To launch a nuclear payload in the form of ship, how big would that be, I think such would depend a bit on the ship and the gravity or planet right? SO would this mean we would trying to land possibly to giant cluster bomb of nukes, or fly that in space?

 

No one is talking about riding a nuclear bomb into space e or even orbit, no nuclear explosion is possible with this rocket design. The payload is not nuclear, in fact the payload of the suggested space craft is as much as 2,000,000 pounds from a space craft massing the same as a Saturn five moon rocket. For the record the Saturn Five didn't have a payload of even close to 2,000,000 pounds.

 

 

This in regards to nuclear technology powering space travels is a serious issue? I don't think chemical rockets always proved to be safe in the first place, but in regards to impact whats worse?

 

Chemical rockets are simply not powerful enough to support any real space effort, safety protocols on these rockets along with remote landing take off sites would mitigate any real risk. We are not talking about tons of radioactive fuel, just a few pounds, Each and every atmospheric nuclear test released many times as much as the absolute worst case scenario of a nuclear light bulb rocket failure. there were many of these nuclear tests, the world didn't come to an end. We are not talking about crashed space craft falling everywhere several times a year. Even one crash would be a highly unusual event and wouldn't release enough radio-nucleotides to be the "end of civilization or even noticed in the grand scheme of things

 

I honestly think space stations orbiting planets or just in space themselves is probably a better answer. Other technology I think would not only prove safer in terms of how much a threat in how many ways that would still make space travel a reality, I mean we dont even know I think really what we could do until we get past the current stage which barely has a space station capable of supporting life without aid yet by any means, its a big of a jump to say it has to be nuclear for anything more of a future to exist for such.

 

Can you suggest a technology that can lift the payloads nesesarry to build a real space station? a tecnology to make space travel both safe and economical? If you can i await the info with baited breath.

 

 

I would like to close with this question. Lets say you want to make a ship that will carry 1000 people with correct life support for say some year long journey then land with such system intact on a earth sized planet, would or how could nuclear technology be made safe really for just that process? What if you change the numbers to ten thousand on some decade long journey? Do we have to have tons of little space shuttle like spaceships, I think that means lots of nukes flying around though.

 

first of all we are not talking about carrying 1000 people, we are talking about launching payloads into space. payloads to build space stations, build interplanetary space craft, satellites, Moon bases, habitats. these things cannot be done in any realistic way by chemical rockets. A 2,000,000 lb payload would be capable of doing things we only dream of at this time. No other technology promises so much for so little risk.

 

The issue about exposure has merit, any place on earth in which nuclear reactors have had issues its been nothing but harmful to people. There is bacteria under the site in handford washington for instance that via mutation has actually come to be able to survive in soil pretty much laden with toxic by products and waste. These are the real issues because the ships themselves would become life support and nuclear accidents truly represent that much more of a threat giving the situation such as using it to travel in space or even land such equipment.

 

The nuclear reactors we have now are old technology, comparing what we have now to 21st century technology is like assessing the safety of air travel by looking at WW1 bi planes. having said that it wouldn't be fair not to point out that most of the current reactors have been completely safe, doom sayers of the death of the earth from nuclear reactors have proved false. Radiation is a part of life, there have even been natural nuclear reactors in places on the earth. For our civilization to go forward we have to use nuclear power, no other technology can take us to the future.

[npts2020]

If we had to launch a ship ASAP this would be a logical choice for doing it. I think most of the objections are not well founded in facts, however. Right now there are many "closed" environments called submarines that use exactly a reactor for an energy source. Furthermore, they have been in operation for over 50 years. IMO the only valid argument against a well designed nuclear plant is proliferation issues. Anyone who can understand refining technology and how a reactor works can build a nuclear bomb. If in fact we should worry about terrorists or rogue states obtaining and using one, how many people do you want with that kind of knowledge? The more you use the technology, the more chance of having someone willing to use their knowledge for undesirable purposes.

[foodchain]

Here is one possible scenario I picture. Do make say nuclear rectors capable of large scale operations in the U.S that would for the sake of safety require a massively integrated approach that has to remain fit for I would say also a rather long time after construction. You would have to have highly detailed understanding on so many things that would make up such an environment, geography, geology, and really with just those two disciplines it would require a lot in individual aspects that belong in those fields.

 

Then you would have to have this be able to work in concert with any concentrated desire to send large quantities of people into space using such nuclear means to power such. The site would have to be built to house I would suggest rater large misses unless we used tiny little ships. In either case we would have nuclear energy so that the ship could break the earths escape velocity and make it into space.

 

Then if this works you have at that point ships traveling through space for whatever duration of time on nuclear energy. In this case you have to deal with the ship being able to withstand any technical issues with a reactor for instance to make success a reality.

 

I am not saying its impossible I just think the landing of mass nuclear infrastructure in the first place is something questionable. We are in a position now, thanks to fossil fuel consumption and technology to begin to at least appreciate trying to understand environmental impact. In all reality I think America should just use its reserves while generating alternative energies such as solar for example, I do know that nuclear energy does have some qualities for this issue, yet what realistic picture do we have of such in the real world?

 

Nuclear tech exists at university level without melting down, and I know it has other applications also that don't generate three mile island stories. Such also has other points that seemed to lack neglect. What do you do for instance with medical waste alone that is harmful because of radioactivity? I do not think any sound answers exist for that, most of the time I think such materials can be found in the form of landfills. Now France has moved to generate I think at least 70% of its energy from nuclear, if anything they would be somewhat a real model for how such technology plays out in regards to pollution and populations I think.

[CaptainPanic]

Okay, so it blows up.......It's fairly simple to calculate the activity(how radioactive) of the debris.

[math]A=N \lambda[/math] where A is the activity, N is the concentration, and [math]\lambda=\frac{\ln 2}{t_{\frac{1}{2}}}[/math]. Now, the fuel has a half life of millions of years. I guess we just need to know how big the explosion is, how much drifts down into the atmosphere, and how strong the wind is.............a rough estimate is that the activity due to such explosion would be extremely negligible.

 

The radiation from all the nuclear explosions (both planned tests and Chernobyl) is indeed negligible. Still, I think that it's not just emotions that people don't like to live near test sites or Chernobyl. I think that's because there is a significant difference between local radiation (when you're close to the source) and the average on earth. Personally, I am not worried about Chernobyl or any tests, but some Ukrainians and some people who used to live near Bikini might think different.

 

Storage for the radioactive fuel can be easily built to with stand impact. Cracking open an empty reactor is no big deal.

That one we can calculate. Say that the rocket reaches a speed of 6000 m/s, which is a realistic velocity for reaching orbit. Then due to some error it heads for the surface again. It has a very large mass and relatively small surface area, so that means it will not slow down a lot in the atmosphere.

 

The kinetic energy of 1 kg of material is :

 

[math]E = 0.5\cdot{m}\cdot{v^2} = 0.5*1*6000^2 = 18 MJ. [/math]

 

All of that energy will go into heat:

 

[math]E = Cp*m*\Delta{T}[/math]

 

Let's choose a Cp value of 1000 J/kgK, as most metals have a lower value than that.

 

[math]\Delta{T} = \frac{E}{C_p*m} = \frac{18\cdot{10^6}}{1000\cdot{1}}=18000 K[/math]

 

That means that metals will melt. And that means that you cannot be certain that the storage will survive. Of course we have materials that can withstand airplane crashes (black boxes usually survive). But airplanes have speeds which are an order of magnitude slower.

 

So, now the discussion really is:

Do we find it acceptible that sometimes a few pounds of nuclear material (plus a lot of non-nuclear material) come falling down at a random place on earth? Or do we prefer to have only non-nuclear material falling down randomly (from conventional rockets).

 

I'm not sure. I agree that statistics say that it's all safe... but in the unlikely event that a crashing rocket comes down on Manhattan, the effects will be a lot worse than the 2 planes that hit the twin towers. (Ok, that last remark was definitely in the emotional category).

[big314mp]

CaptainPanic has a good point, which led me to another idea:

 

What if instead of trying to contain the radionuclides, you dumped them into the upper atmosphere, so that they scatter over a huge area, so the localized effect is negligible.

 

It would still be a PR disaster, but perhaps clean up costs could be avoided.

[Mr Skeptic]

No, that would make it a PR disaster that would likely prevent it from ever being built.