[Mars]

were to focus on space exploration/exploitation, how long would it be before there was a significant breakthrough (i.e. Moon colonized, Mars colonies, solar economy, etc.)

[TrashMan]

Entire world? Not much I'd guess.
That's a LOT of money and will focused towards a single goal.

[Mars]

I'm thinking pre-apocalyptic scenario,

[IceFire]

There would still be massive time resources involved and major projects reach a critical mass where you can no longer throw people at a problem as its just too many to manage effectively, too much information spread out, and too much time needed to keep relevant people up to speed.

If you wanted to achieve something...it'd have to be several projects with equal funding or something like that.  Even then...I doubt we have the technology, in a scenario where we had to abandon the planet, to build what we'd need to sustain ourselves.  Necessity is the mother of all invention but I still think we have decades of scientific progress before we'll be approaching the sorts of materials, electronics, and scientific knowhow, to produce some sort of world ship to escape in.

[castor]

World econmy would collapse long before anything substantial got done with those terms

[Dark RevenantX]

It shouldn't be too hard to convert the sun's mass/energy into usable mass if we get that kind of technology...

[Bob-san]

IF we had political differences settled, I think it'd be doable in 20-30 years. With the vast amounts of knowledge we have, focusing more at making sure different approaches do it first would be best. Having a half a dozen different ways to get where you want to go is important, and making sure all possible research is done is also important. Focus on refining theories and then figuring out ways to bypass our current shortcomings.

[NGTM-1R]

Truthfully, if we could find the political will and the funding, we could probably establish a workable colony on Luna or Mars within five years, ten at the outside. The problem has been examined for decades by official agencies and gifted amateurs alike, and we have a fairly good understanding of what it would take. It would take at least a few years to become self-sufficent after being founded, but that is well within the realm of possiblity too.

However, this would also be a blantant case of No Plans No Prototype No Backup. There would inevitably be problems in the execution, and if it outright failed, it would probably do so in a spectacular fashion.

[Bob-san]

Truthfully, if we could find the political will and the funding, we could probably establish a workable colony on Luna or Mars within five years, ten at the outside. The problem has been examined for decades by official agencies and gifted amateurs alike, and we have a fairly good understanding of what it would take. It would take at least a few years to become self-sufficent after being founded, but that is well within the realm of possiblity too.

However, this would also be a blantant case of No Plans No Prototype No Backup. There would inevitably be problems in the execution, and if it outright failed, it would probably do so in a spectacular fashion.

Agreed. I think if we could have a collective space race, we could put a colony on the moon in 5 years, a colony on Mars in 10, and do better surveys of each planet and microplanet in our solar system. Futhermore: in 20 years, I think we'd have sleeper-ship tech and be ready to launch a few hundred people that way. In 30? We'd be able to send hundreds into space regularly.

What I'd like to see, though, is drug development for space. The microgravity has caused some odd mutations and the general destruction of quite a bit of those fragile samples we've sent up.

[BloodEagle]

*snip*

Agreed. I think if we could have a collective space race, we could put a colony on the moon in 5 years, a colony on Mars in 10, and do better surveys of each planet and microplanet in our solar system. Futhermore: in 20 years, I think we'd have sleeper-ship tech and be ready to launch a few hundred people that way. In 30? We'd be able to send hundreds into space regularly.

What I'd like to see, though, is drug development for space. The microgravity has caused some odd mutations and the general destruction of quite a bit of those fragile samples we've sent up.

How long does it take to travel to Mars, again?

[redsniper]

Months

[BloodEagle]

Months for a small rocket carrying a small unmanned probe, or months for a large ship carrying all of the personnel and equipment necessary for the production of a colony?

I can't wait for working ion-drives. 

[Aardwolf]

Aren't ion drives slower than conventional rockets?

[Bob-san]

Aren't ion drives slower than conventional rockets?

Yes---and useless to escape in any less than orbit. They start out slow, but will get much faster with time. If you had a decent ion-drive and reactor, you could send it for millions of lightyears, accelerating as time passes. By the end, it could be like .99999999999999999999c.

[Androgeos Exeunt]

What's the difference between ion and fusion?

[Mars]

Ion engines accelerate a small amount of gas ions (usually a noble gas of some sort) to a very high speed. Over time, these will accelerate the vessel to extremely high speeds, but the rate of acceleration is extremely slow. Humans have already successfully used ion engines to power unmanned spacecraft, it is much cheaper and significantly faster (over time) than chemical rockets in many cases.

Fusion engines would fuse Hydrogen atoms (either Deuterium and Tritium, or four plain Hydrogen atoms) together to form some isotope of Helium, releasing a large amount of energy. I'm not entirely clear how this would be harnessed as an engine, but it would likely result in an extremely high rate of acceleration. All fusion engine designs are hypothetical at this point.

[Androgeos Exeunt]

Hmm...in that case, is it possible to channel all the energy released by a helium isotope into some kind of thruster such that it comes out like a jet engine?

[Akalabeth Angel]

So

Who's going to reach mars first? The US or China?

[TrashMan]

Space travel is currently limited by funding. A lot of ideas are discarded simply because they are too expensive. With the whole world budget behind space  exploration, a lot of hurdles would be lifted.

[Aardwolf]

What's the difference between ion and fusion?

That they're completely unrelated?

Also, ion drives are for propulsion, and ... fusion 'drives' don't make sense. And nuclear fusion as a power source for a ship is not practical with today's tech.