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Robert Zubrin: the importance of space for mankind.

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ruveyn
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06 Jan 2012, 9:57 pm

androbot2084 wrote:
Zubrin invented the nuclear salt water rocket which is basically an atomic explosion that never dies until all the fuel is consumed. Pretty scary stuff.


Utter and complete balderdash.

ruveyn



iamnotaparakeet
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06 Jan 2012, 10:10 pm

ruveyn wrote:
androbot2084 wrote:
Zubrin invented the nuclear salt water rocket which is basically an atomic explosion that never dies until all the fuel is consumed. Pretty scary stuff.


Utter and complete balderdash.

ruveyn


For as much hype as and-robot is placing upon the NSWR, it's just a variety of nuclear thermal rocket which uses dissolved U235. It's never been built, but only designed.

http://www.projectrho.com/rocket/engine ... ter_Rocket

http://en.wikipedia.org/wiki/Nuclear_salt-water_rocket



androbot2084
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06 Jan 2012, 10:30 pm

Wikipedia clearly describes this insane device as a hybrid between a fission reactor and a fission bomb.
In many ways this device is even more provocative than an atomic bomb because the explosion is continuous and never dies until all the fuel is consumed which could last for days. This nuclear reaction is so violent that containment is impossible with any material known to man so the violent nuclear reaction occurs outside of the vehicle creating an open torch in space or if launched from Earth a giant mushroom cloud that ascends into the heavens.



iamnotaparakeet
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06 Jan 2012, 10:32 pm

androbot2084 wrote:
Wikipedia clearly describes this insane device as a hybrid between a fission reactor and a fission bomb.
In many ways this device is even more provocative than an atomic bomb because the explosion is continuous and never dies until all the fuel is consumed which could last for days. This nuclear reaction is so violent that containment is impossible with any material known to man so the violent nuclear reaction occurs outside of the vehicle creating an open torch in space or if launched from Earth a giant mushroom cloud that ascends into the heavens.


You should work in a marketing department, or do you already? Perhaps you should market yourself as a caricature artist, as you're unfortunately very highly skilled in acting as a caricature of people who actually give a damn about the actual colonization of space.



Jono
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09 Jan 2012, 9:41 am

I like Dr Zubrin's arguments about space colonization. However, I think he may have been a bit too ambitious when he tried to argue for the Mars First option as the replacement for the Constellation Program.



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09 Jan 2012, 10:14 am

iamnotaparakeet wrote:
ruveyn wrote:
androbot2084 wrote:
Zubrin invented the nuclear salt water rocket which is basically an atomic explosion that never dies until all the fuel is consumed. Pretty scary stuff.


Utter and complete balderdash.

ruveyn


For as much hype as and-robot is placing upon the NSWR, it's just a variety of nuclear thermal rocket which uses dissolved U235. It's never been built, but only designed.

http://www.projectrho.com/rocket/engine ... ter_Rocket

http://en.wikipedia.org/wiki/Nuclear_salt-water_rocket


The physics is sound but I don't know if it's practical. A rupture in the engine could lead to a runaway chain reaction, for instance.



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09 Jan 2012, 10:48 am

Since a nuclear salt water rocket is not considered a bomb therefore it does not violate the nuclear test ban treaty. Political acceptance would be difficult because it could be argued that this device is worse than a bomb because it never fizzles out.
However for an Earth based launch a fusion power rocket would be required to minimize the fallout.



ruveyn
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09 Jan 2012, 10:55 am

androbot2084 wrote:
Since a nuclear salt water rocket is not considered a bomb therefore it does not violate the nuclear test ban treaty. Political acceptance would be difficult because it could be argued that this device is worse than a bomb because it never fizzles out.
However for an Earth based launch a fusion power rocket would be required to minimize the fallout.


Has it ever been built and tested? What are its safety parameters? What are the costs? Can it generate enough power to lift a man rated vehicle into orbit?

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09 Jan 2012, 10:59 am

ruveyn wrote:
androbot2084 wrote:
Since a nuclear salt water rocket is not considered a bomb therefore it does not violate the nuclear test ban treaty. Political acceptance would be difficult because it could be argued that this device is worse than a bomb because it never fizzles out.
However for an Earth based launch a fusion power rocket would be required to minimize the fallout.


Has it ever been built and tested? What are its safety parameters? What are the costs? Can it generate enough power to lift a man rated vehicle into orbit?

ruveyn


since they are similar in concept to the nuclear thermal rocket they probably have similar attributes,

they have been tested a couple dozern times, there should be some data available somewhere, but in essence they all showed to have a much higher power to wheight ratio than any chemical rocket, if wiki can be trusted directly that is.


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ruveyn
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09 Jan 2012, 11:05 am

Oodain wrote:

they have been tested a couple dozern times, there should be some data available somewhere, but in essence they all showed to have a much higher power to wheight ratio than any chemical rocket, if wiki can be trusted directly that is.


I will believe it when I see data on a full scale test vehicle. Nuke or no nuke the rocket has to hurl a reaction mass out the back at very high velocity (high kinetic energy). Maybe this thing might work in a vehicle constructed in orbit and not having to climb out of the Earth's gravity well. Ion rockets so constructed already have been built and flown.

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09 Jan 2012, 11:06 am

Most of those questions can be solved mathematically. And yes a big enough nuclear powered torch ship has enough thrust to lift whole cities into orbit while providing excellent fuel economy. As far as costs goes I would like to see a rocket built with the same cost as the Saturn 5 Moon rocket weighing about 3000 tons and capable of sending 1500 tons to Mars rather than 50 tons to the Moon.



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09 Jan 2012, 11:11 am

ruveyn wrote:
Oodain wrote:

they have been tested a couple dozern times, there should be some data available somewhere, but in essence they all showed to have a much higher power to wheight ratio than any chemical rocket, if wiki can be trusted directly that is.


I will believe it when I see data on a full scale test vehicle. Nuke or no nuke the rocket has to hurl a reaction mass out the back at very high velocity (high kinetic energy). Maybe this thing might work in a vehicle constructed in orbit and not having to climb out of the Earth's gravity well. Ion rockets so constructed already have been built and flown.

ruveyn


4000 megawatts of power has been test fired succesfully.

with the small orbital engines having an output of some 500 megawatt.

again do a search yourself i think you have a much better grasp of what is required of the engines.


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09 Jan 2012, 11:30 am

So what percentage of the speed of light can this rocket achieve?



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09 Jan 2012, 11:47 am

Jono wrote:
I like Dr Zubrin's arguments about space colonization. However, I think he may have been a bit too ambitious when he tried to argue for the Mars First option as the replacement for the Constellation Program.


Zubrin's been arguing for Mars way before the Constellation program though. For as much as the Constellation program sounded like a good idea, Bush should have required that it be implemented during his presidency rather than wait for the next guy. Going to Mars, using SpaceX at a fourth the cost of the Shuttle program to launch 15 flights per year to Mars, seems like a better idea to me than just slowly fiddling about in Low Earth Orbit and doing nothing until the end of time.



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09 Jan 2012, 12:14 pm

androbot2084 wrote:
So what percentage of the speed of light can this rocket achieve?


How long can it burn? A small acceleration of a long period of time can produce a much higher final velocity than a short burn followed by free fall.

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09 Jan 2012, 12:32 pm

Also, the final velocity of the ship is dependent upon the velocity of the exhaust propelled outward times the ratio of the mass of propellant to the mass total. You want to have a ship travel as fast as possible, you increase the velocity of the propellant and and percentage of mass composed of fuel.