By conventional I meant anything sub light speed.
We can reach other stars with just sub-light speed. The main issue is the process of surviving the journey.
I'm pretty sure all we can achieve right now is 10% speed of light with a fusion based Orion drive (which we still would need to perfect fusion before we could do it. By the way, the Orion drive is wicked cool. You drop nukes behind you and set them off. Viola! Instant propulsion)
The 'Orion' drive is not the only kind of nuclear pulse propulsion theoretical framework that we have. It's just the only one widely publicized. 'Theoretically' we can 'easily' achieve 60% speed of light because until 60% the speed of light the increase in 'relative' mass is negligible. All we need to do is to keep 'detonating' additional nuclear fuel to incrementally produce acceleration. Once a spaceship is accelerated to 60%, it will keep going at that velocity for a very long time. Simply put, more fuel = more acceleration. The only limit to how fast we can move is set by the general theory of relativity; which is the speed of light. Anything below the speed of light, we can reach. It's just that nuclear pulse and ion engines have better thrust-mass ratio than rocket engines. Theoretically we can reach 99% the speed of light also; the problem is that we'll need like a billion times more fuel to accelerate from 60% to 99% than what's needed to accelerate from 0% to 60%. Current Earth's stockpile of fissile materials will not be enough to provide those... billion tons of nuclear fuel. But we can provide a few tons, which will be enough to accelerate a ship to 60% the speed of light.
Assuming negligible effect of relativity until 60% the speed of light, we can assume that:
20kg of fissile material will produce 1 kiloton yield (davy crocket has 50 lb warhead and can be dialed to produce 1 kt)
1 kiloton = 4.2 × 10^12 Jso 2 tons of fissile fuel would mean
4.2 x 10^14 J.
To convert this to thrust we just use
1/2 vt^2. 1/2 mv^2. (lol xD)
Ah well we'll need calculator from this point so I'll just leave it at that.
But the theoretical framework behind nuclear pulse engine is really that simple.
I know we as humans can definitely reach 60% the speed of light, because we understand the framework behind it.
I haven't really seen any references of Ion thrusters even coming close to that yet.
http://www.reddit.com/r/science/comments/87hhn/the_cancelled_project_orion_a_spaceship_that/
It's not because we don't have the skills to achieve that technology but it's just that we don't need to achieve it. We don't have a use for interstellar drives yet so we didn't spend money for it.
A warp drive just creates a warp bubble around your ship. You don't need a singularity to create one. A warp drive works by compressing space time in front of you, and expanding it behind you. Almost like a jet engine, except for space/time instead of air.
Ah I see. I thought you meant something like 'warping' space, as in, bending it to create a portal or something. Creating a portal (connecting two space-time into a single space-time) requires singularity.
But regardless, we don't have anything up in the sky or on earth capable or rather, sensitive enough yet to detect gravitational waves (usually given off by 2 black holes or neutron stars colliding). Though, they're getting ready to put one up in space. LISA as it's called, will be launched in 2011. Still, I highly doubt it will be strong enough to detect the warping of space by a warp drive.
Yeah, and even if we had the technology to detect gravity waves it will still be useless because they'll be here instantly anyway.
Although I'd much prefer to discuss an easier subject. >.> For one, the thread title reads
'South Korea succeeds in launching its first domestic space vehicle but fails-', so...
