There is a very good prospect that we will find an Earthlike planet reasonably close in the next couple of decades. I've got to believe the very idea of a "new earth" would have a huge psychological impact on humanity. This would be the point at which we would have an extraordinary incentive for an interstellar probe. The thought of exploring a "new earth" excites the hell out of me. I hope I can live to witness it.

I started thinking of the many technologies that might be needed to realize such a probe. We would definitely need nanotechnology to create an ultra low mass but very sophisticated probe. Could we accelerate it with external lasers sufficiently to make the crossing? If so, how would it stop? Or by that time could we garner enough anti-matter to make an anti-matter engine to boost it on its way? Maybe some combination of such energy plants would be necessary.

Taking it even further maybe in the next century we could conceive of seeding another world with earth life (including our own). I think we would need some sort of hyper-intelligent bootstrapping probe to do that job. It would carry life in only its most germinal states. It would first need to bootstrap up on energy and material needs. Maybe it could prospect for the appropriate asteroid to build power plants and fueling stations. Then once that was done it could build scads of helper probes to garner all the materials necessary to colonize and land on the prospective "new earth." Could a machine gestate and teach the very first humans on a new world? Given the latest advances that indicate we may be able to put higher mammals (including humans) into hibernative states, we might send follow on adult humans in cold sleep, realizing the ideas of some of the first sci-fi books. Science fiction or a vision of the future to come?