Antimatter Rocket Speed

[Jon0815]

I've read that the fastest possible speed for a fusion-powered spacecraft that carries its fuel with it, is about 1/3rd light speed.

 

I'd like to know- what is the fastest possible speed for a spaceship that uses antimatter as fuel?

[Schrödinger's hat]

I've read that the fastest possible speed for a fusion-powered spacecraft that carries its fuel with it, is about 1/3rd light speed.

 

I'd like to know- what is the fastest possible speed for a spaceship that uses antimatter as fuel?

 

This should probably be in speculations as we can't even make a billionth of a nanogram of antimatter.

 

It all depends on how much fuel you take with you, Antimatter is a dense enough fuel that very high gamma (0.99c or so) could be achieved if enough could be produced. However things would start becoming prohibitive above about 0.9c as the fuel required would scale (at best linearly) with gamma or [math]\frac{1}{\sqrt{1-\frac{v^2}{c^2}}}[/math]

 

Looking at a plot (v=1 on this graph is the speed of light) of this can be instructive (see how quickly it increases as you get past v=0.9c).

[swansont]

I've read that the fastest possible speed for a fusion-powered spacecraft that carries its fuel with it, is about 1/3rd light speed.

 

I'd like to know- what is the fastest possible speed for a spaceship that uses antimatter as fuel?

 

I think you need more information to answer the question. There are assumptions about the rocket and payload that enter into the calculations.

[CaptainPanic]

I've read that the fastest possible speed for a fusion-powered spacecraft that carries its fuel with it, is about 1/3rd light speed.

 

I'd like to know- what is the fastest possible speed for a spaceship that uses antimatter as fuel?

Based on what?

 

In principle, more stages means you can achieve a higher speed.

 

If you have a theoretical spaceship carrying its own fuel, and capable of reaching 1/3rd light speed, then I can attach another stage to it, and you bring your spaceship to, say 1/6th of the light speed. Then you can ignite yours, and since you already have some initial speed, you should get to more than 1/3rd light speed.

 

Or is a stage not considered "carrying its own fuel" anymore?

[Neotropic]

A ship fueled with antimatter wouldn't be a good idea in a universe filled with matter.

 

 

[CaptainPanic]

A ship fueled with antimatter wouldn't be a good idea in a universe filled with matter.

Well... in a similar way, you would think that it would be a bad idea to carry highly flammable fuels in an atmosphere full of oxygen. Yet, we do that all the time.

[Neotropic]

Well... in a similar way, you would think that it would be a bad idea to carry highly flammable fuels in an atmosphere full of oxygen. Yet, we do that all the time.

 

Thats a good point.

Edited April 13, 2011 by Neotropic