Berster7 wrote:
You don't have an engineering background do you?
It shows.
It's a very simple principle, actually doing it would be incredibly difficult. Whereas NERVA based designs are very complicated in principle, but the application of these principles is easy. The number of things that could go horribly wrong with pulse based designs (not to mention all the other things) makes them impractical.
You really need to start getting your information from somewhere that isn't Wikipedia. It is not a strong scientific source and doesn't show both sides of this picture at all.
Hey look, you said
nothing here. You attack my credibility, you attack the credibility of sources, you say "the number of things that could go horribly wrong...makes them impractical", and
not once did you actually give a reason as to why I am wrong, why my sources are wrong, what exactly could go wrong. Now I haven't finished reading your post but this entire block of text is completely pointless.
Berster7 wrote:
This statement really shows you haven't understood the main risk here. It is not from any sort of nuclear reaction - it's from the spacecraft exploding in a catastrophic manner and showering a huge area with radioactive material. Those are the risks of using NERVA based designs and you would have a greater risk transporting the much larger quantities of nuclear material into orbit to fuel a nuclear pulse based craft. It's a much more significant risk because of the volumes of nuclear material involved that could irradiate huge areas. It has already been demonstrated in loads of tests that there is no way to reliably secure a payload against catatrophic failure - if the rocket blows up, the payload is exposed.
hurr durr that is exactly what I was talking about. I don't know how you missed this, I even used the word payload.
Flaming_Maniac wrote:
It is not particularly easy to instigate a nuclear reaction without making an effort, and it is certainly very difficult to accidentally start a nuclear reaction when the payload has been secured against even a catastrophic failure.
So a) an accidental nuclear reaction even in the event of catastrophic failure is less than unlikely and b) we can build a black box that can secure 1 gram of nuclear material after you assume there is no accidental nuclear reaction. Unless of course you can provide proof that "It has already been demonstrated in loads of tests that there is no way to reliably secure a payload against catatrophic failure"? I mean if it has been demonstrated in loads of tests, why didn't you provide one? If you are willing to bring relatively small loads at a time to build up the stockpile you need over many, many chemical launches the additional risk is marginal. 1 gram is not a realistic figure, it is a figure to demonstrate my point. The cost of any such nuclear pulse rocket program would be so great that any number of launches to bring parts to be assembled in space, including the fuel, would be completely justified.
Flaming_Maniac wrote:
It is also impractical to launch such a craft by chemical rocket (since the craft would need to weigh so much), so it would need to be built in orbit or be able to get into orbit under nuclear pulse propulsion - madness. Building something like this in orbit is unrealistic at present.
Of course it would be assembled in space. This argument started from me stating that this would obviously be built in space.
Why is it unrealistic? Technologically it's not unrealistic. Given the drive we are perfectly capable of assembling large objects in space. Politically yes, it is unrealistic, but politically any of the missions that this type of technology would be used for is unrealistic. In the current political climate primarily because of the current economic climate going to Mars in the next ten years is completely unrealistic. Going to the moon in the next ten years is unrealistic. Reworking the goddamn shuttle system in the next ten years is unrealistic. But, when we are looking to seriously step up our space exploration, we would be seriously looking into assembling much larger structures in space, be it vessels, planetary bases, stations, whatever.
Berster7 wrote:
So:
Immense cost (really, truly, horrifically immense cost - we're talking tens of trillions here).
High risk.
Untested.
Barely possible with existing technology.
Suspected high failure rate (through damage to the pusher plates).
Vs.
Low cost (after a few launches the technology would have paid for itself).
Low risk (low volume of nuclear material carried into orbit the only risk).
Successfully tested.
Easy to implement.
Demonstrated low failure rate (0).
As I said, for the foreseeable future, nuclear pulse technology is not feasible. It is not practical. It is not safe. It is not affordable. It is by no means certain that it would work and if it did work, there is very little evidence to indicate how reliable it would be.
It's the sort of concept that physicists love and engineers loathe - because it's a nice idea in theory, but the practicalities make it unthinkable.
In 100 years time, maybe we could build a nice nuclear pulse powered ship on the Moon which could be used to travel really huge distances. Because huge distances are all it would be worth using it for - it's too stupidly dangerous and expensive for anything else and there are much more sensible alternatives that could be used.
Now I'm going to pare out everything that you didn't back up with an example, or a source, or even an ounce of logic as to why something may be true.
Berster7 wrote:
Give me a fucking
reason why it is such high risk, or is barely possible (which is already a laughable way to state it because something that is barely possible can work just as well as something that has been possible for hundreds of years), or why it has a "suspected high failure rate through damage to the pusher plate"). Your analysis of the thermal nuclear system is as if not more flawed, but I'm not going to sit here going line by line about how stupidly devoid of thought it is. All rhetoric nonsense.
Berster7 wrote:
If you seriously think nuclear pulse rockets are something that could be used anytime over the next decade for anything other than a global catastrophy where safety and cost cease to be an issue, then you are mad.
Fuck off with this decade bullshit. I never said anything about the next decade.