First rocky planet found outside solar system

[DGuller]

I imagine that filling up enough fuel might be of some difficulty for a voyage that requires you to travel at the speed of light.

[Josquius]

Reaction mass is the reason why we can't.

How?
No way I can think of looking at reaction mass shows it to be a big problem.

The main problems are of course there being no point and the cost.
Assuming a civ 2 type scenario where we for some reason have to bankrupt ourselves to get to Alpha Centauri....Sure. You can make your spaceship which gets you there in 50 years. Thats within our capabilities using one of the many nuclear propulsion options.
The crew though will be long dead beyfore the 50 years is up. Thats not within our capabilities.

[Tonitrus]

Me travelling to Alaska to stalk and slay the vile beast is theoretical but certainly possible.

No one has actually seen Katmai...just evidence of a slight drop in brightness when other objects pass in front of him. 

[Caliga]

Beware the katmaiwock, my son.

[Neil]

How?
No way I can think of looking at reaction mass shows it to be a big problem.

The main problems are of course there being no point and the cost.
Assuming a civ 2 type scenario where we for some reason have to bankrupt ourselves to get to Alpha Centauri....Sure. You can make your spaceship which gets you there in 50 years. Thats within our capabilities using one of the many nuclear propulsion options.
The crew though will be long dead beyfore the 50 years is up. Thats not within our capabilities.

Reaction mass is always a problem.  In order to move forward, you need to throw something out the back.  And it's a long way to have to go, especially if you have to accelerate and deccelerate the whole way.

As for  nuclear pulse propulsion, it doesn't work.

[BuddhaRhubarb]

How?
No way I can think of looking at reaction mass shows it to be a big problem.

The main problems are of course there being no point and the cost.
Assuming a civ 2 type scenario where we for some reason have to bankrupt ourselves to get to Alpha Centauri....Sure. You can make your spaceship which gets you there in 50 years. Thats within our capabilities using one of the many nuclear propulsion options.
The crew though will be long dead beyfore the 50 years is up. Thats not within our capabilities.

Reaction mass is always a problem.  In order to move forward, you need to throw something out the back.  And it's a long way to have to go, especially if you have to accelerate and deccelerate the whole way.

As for  nuclear pulse propulsion, it doesn't work.

You could bring Jaron, maybe Tim as ballast.

[swallow]

How?
No way I can think of looking at reaction mass shows it to be a big problem.

The main problems are of course there being no point and the cost.
Assuming a civ 2 type scenario where we for some reason have to bankrupt ourselves to get to Alpha Centauri....Sure. You can make your spaceship which gets you there in 50 years. Thats within our capabilities using one of the many nuclear propulsion options.
The crew though will be long dead beyfore the 50 years is up. Thats not within our capabilities.

Reaction mass is always a problem.  In order to move forward, you need to throw something out the back.  And it's a long way to have to go, especially if you have to accelerate and deccelerate the whole way.

As for  nuclear pulse propulsion, it doesn't work.

Once you've escaped the gravity field, you wouldn't need  reactant mass.  Obviously when you get ther you'd need force to slow down.

[Neil]

Once you've escaped the gravity field, you wouldn't need  reactant mass.  Obviously when you get ther you'd need force to slow down.

Solar escape velocity is 42.1 km/s.  You could happily rocket up to that velocity, but you'd only be covering 1.329 billion kilometres every year.  That means that your trip to this 500 light year distant planet would take you roughly 5 million years.  Even a short jaunt to Proxima Centauri would take 32,000 years.  How would you feed the passangers and crew for such a long period of time?  How to keep them breathing?  Keep them warm?

[Josquius]

As for  nuclear pulse propulsion, it doesn't work.

How so?
Orion (yeah yeah, never going to happen, we're talking just theoretical an damn the hippies here though) is largely regarded as doable.
And why don't 'nuclear rockets' of a more realistically doable type work?

[Neil]

As for  nuclear pulse propulsion, it doesn't work.

How so?
Orion (yeah yeah, never going to happen, we're talking just theoretical an damn the hippies here though) is largely regarded as doable.
And why don't 'nuclear rockets' of a more realistically doable type work?

Orion is undoable because of wear and tear on the pusher plate.

The other types don't work for voyages of that length because of their thirst for large quantities of reaction mass and insufficient power.  Without the ramjet, man has no hope of reaching the stars.

[ulmont]

Orion is undoable because of wear and tear on the pusher plate.

The wiki seems to disagree:

calculations and experiments indicate that a steel pusher plate would ablate less than 1 mm if unprotected. If sprayed with an oil, it need not ablate at all (this was discovered by accident; a test plate had oily fingerprints on it, and the fingerprints suffered no ablation).

[Agelastus]

Presumably for reaction mass along with crew quarters, the ideal combination would be an ice asteroid with a rock core.

Anyone know where there is one?

[PDH]

I support any attempt to shoot Tim 500 light years away.

[Ed Anger]

I support any attempt to shoot Tim 500 light years away.

Into a black hole.

[PDH]

I support any attempt to shoot Tim 500 light years away.

Into a black hole.

With knobs.