Matter/Anti-Matter: Explaining Space Travel Applications

[DaveC426913]

As a drive-fuel, I can't think of anything worse. One thing Star Trek definitely appreciated was that the only 'fail safe' a matter-antimatter reactor can have on a spaceship, is to be violently ejected. ANY hint of containment failure for the antimatter, any leakage or loss of power, and BLAM, suddenly your whole ship is the other half of the fuel equation.

Of course, the most 'out there' reason would be that an antimatter drive would by definition be almost indistinguishable from a very powerful BOMB. For those victims of Differential Aging returning to a populate in their 'future' (I assume the antimatter rocket goes near c after all), or aliens encountering our intrepid vessel, might shoot first and ask questions later.

Well, it's all a matter of technology comfort-level. A century ago, the idea of harnessing nuclear power safe enough to power a vehicle was ridiculous too.

 

[Frame Dragger]

Well, it's all a matter of technology comfort-level. A century ago, the idea of harnessing nuclear power safe enough to power a vehicle was ridiculous too.

Define 'ridiculous'. Some people would find the notion of floating nuclear cores with 16 verticle launch tubes filled with nuclear WEAPONS to be 'less than safe'.

The difference is this: antimatter is always going to annihilate with matter upon 'contact', and that is a unique danger of any fuel. Sure, some things are pyrophoric, or hydrophoric, etc... but 'matter' phoric? Something that will explode VIOLENTLY if a normal particle even looks at it the wrong way?

Eh. Safe perhaps, but a 'bottle' of antimatter is still going to be indistinguishable from a devestating bomb, and I suspect that would be a bad first impression. After all, you can't just take the reactor from a submarine and turn it into a WMD just by crashing it. You can create environmental havoc, but a 'starship' could turn a city into a smoking crater, and blowing it out of the sky at low altitude isn't an option... that's an airburst. (EDIT: That would be the final point... upon launch an antimatter vessel (containing or fueled by) would be impossible to fail safe.

 

[DaveC426913]

Define 'ridiculous'. Some people would find the notion of floating nuclear cores with 16 verticle launch tubes filled with nuclear WEAPONS to be 'less than safe'.

Yet we do it routinely.

The difference is this: antimatter is always going to annihilate with matter upon 'contact', and that is a unique danger of any fuel. Sure, some things are pyrophoric, or hydrophoric, etc... but 'matter' phoric? Something that will explode VIOLENTLY if a normal particle even looks at it the wrong way?

Agreed. If left to its own devices, antimatter will annihilate.

Then again, hydrogen is almost spontaneously combustive when in the presence of oxygen. And it'd be pretty hard to have a failure in containment without an associated presence of heat, spark or any other ignition source.

 

[Frame Dragger]

Yet we do it routinely.

We're a ridiculous species.

 

[MotoH]

Define 'ridiculous'. Some people would find the notion of floating nuclear cores with 16 verticle launch tubes filled with nuclear WEAPONS to be 'less than safe'.

It is a lot safer than keeping them in concrete bunkers on land!

 

[DaveC426913]

It is a lot safer than keeping them in concrete bunkers on land!

Not sure of zero is any safer than zero. Has there ever been a accidental detonation or contamination either in land silos or sub-silos?


Anyway, the point is that we routinely play with extrremely dangerous substances. Granted, antimatter is an order of magnitude worse (OK, it is probably as bad as bad can theoretically get) but still, failure is failure. We built the Hindenburg. We built the Challenger. etc.

 

[Frame Dragger]

Not sure of zero is any safer than zero. Has there ever been a accidental detonation or contamination either in land silos or sub-silos?


Anyway, the point is that we routinely play with extrremely dangerous substances. Granted, antimatter is an order of magnitude worse (OK, it is probably as bad as bad can theoretically get) but still, failure is failure. We built the Hindenburg. We built the Challenger. etc.

My personal favourite, and I will find an article for more detail later; the Russians (of which I am half) are slapping 3 RMBK-1000 Reactors on a BOAT to supply ready nuclear power for expeditions to Siberia and other locales needing a boost to their grid for a while. These ships will have backup diesel generators (sound familiar yet?), but to run the reactors will require some standard current from the mainland to run the reactors and systems.

Although it IS possible to shield a boat's hull from a molten core, for cost and timing reasons this project is going ahead without such shielding. Radioactive steam boiling from a nuclear reactor that has melted through a ship's hull would be a catastrophe. Ahhh the RMBK-1000... it was good enough to Chernobyl, it'll be good enough for this.

@DaveC: Failure is failure, but an antimatter failure is the highest yield failure per mass possible by orders of magnitude. The fact that either the integrity of an exotic material, or a constant supply of power to some kind of trap would be required to maintain antimatter's segregation from EVERYTHING else means that it is a double whammy. As you've pointed out, the road to progress is littered with failures. The question then, is given that immutable fact, can a planet-bound civilation afford the dangers of a learning curve with anti-matter?

 

[Astronuc]

I'm no expert, but as I see it the problems with using antimatter for rocket propulsion are:

1. Our inability to produce antimatter in useful quantities.
2. Our inability to produce it efficiently.
3. Our inability to store it.

Is there anything else that's not really covered by these reasons?

Answer to question - No.