[renormalised (Carl)]

I'm not feeling so good today, so I won't ramble on too much here with a really long reply...only to say this, you lot are barking up the wrong tree. You have little imagination. You're assuming that we will never be able to break the speed of light barrier and you're talking about the same old boring ways of getting around that have been gone over again and again. All this talk about sending generations ships, DNA carriers etc etc. Won't work and for many of the reasons that you've stated here. Won't work unless you can come up with a way to basically make the information that is being carried immortal. Either totally incorruptible digital or quantum storage systems (for DNA code storage), or you have immortal (or close to immortal) passengers on the generation ships. You also have to have perfect replication of the DNA at the end of the trip if you use the first method. If you use actual DNA, you then have the problems of the storage, plus the degradation of the DNA over time as well as protection from mutation, damage etc etc. If you send people, to make it viable, you're going to have to enormously extend the lifespans of the people onboard, unless you want all sorts of problems occurring with people of normal lifespans living in a confined space for many millenia. The consequences of fooling around with their genetics and their medical condition to create occupants that live for, say, 1000-10000 years are an even greater unknown than sending just DNA in any form. The technology to be able to do this is even further beyond our present understanding than actually designing a workable FTL drive.

If you're going to restrict yourselves that this level, you might as well send robots and forget about it. You'll never explore the galaxy yourselves and will have to do it by proxy. Even there, you'll have problems with the longevity of your equipment...whether they're macroscale robotic craft or nanobots. If they're nanobots, you may have the chance of self-replication built into the design, but then you have the problems of data storage, redundancy, swarm cohesion etc, and even the replication itself.

Ultimately, if your going down the paths you're traveling for ways to get about, you might as well just sit put where we are and forget about interstellar travel. Unless you develop methods of circumventing the light speed barrier (spacetime warp fields, wormholes etc etc), you will not be able to travel to the stars. Unless, of course, you can come up with some "paranormal" way of projecting your consciousness to anywhere at any time.

As for navigation....think!!!. Yes, the stars do move about the galaxy. But you workout how far they move in any one given moment and then you'll have your answer to your navigational problems. It's not traveling at c, or faster, that is the problem. It's creating the starmaps in the first place. The changes in position are easy to map, once you have the template maps drawn up. It's just a matter of accounting for the stars true space velocities and their vectors of travel. Simple 4D mathematics.