I've brought this up before -- e.g., here and here -- but the context was pretty much limited to just getting off the planet, or going as far as colonizing Mars. Turns out, though, that there is no real "final frontier" -- each step we take only opens up a further and greater step, challenging and daunting both. We've already gotten off the planet, after all, and as far as the Moon in exploratory modes, but Mars is now an enormous leap for which we haven't yet mustered either the nerve or rationale. And beyond Mars lie still greater gulfs.
Ultimately, though, the Solar System itself is just a backyard, and it's interesting to find that a few people are already getting serious about looking further out -- so here, for example, is a "Status Report on the Tau Zero Foundation":
Ideally, we want to cover all the technologies and implications related to the ultimate goal of reaching other habitable worlds, and we want to do that in a manner where you can count on the accuracy of our information (which is why we include reference citations so that you can check any questionable assertions). This span includes understanding ‘what’s out there,’ examining all the options for ‘how to get there,’ and being sure to tie this all to its ‘relevance to humanity.’
One of the most hotly debated items is how best to get out there. To be explicit, Tau Zero covers the full span of options, from the seemingly simple solar sails to the seemingly impossible faster-than-light travel. For each option within that span, there are different levels of readiness and performance, and accordingly different types of work.Within that span of options, here's one that seems at least plausible with known technology, and able to reach speeds of between 10% and 92% light:
Failing the discovery of something akin to 'sub-space' we will be forced to obey, in our exploration, the seemingly unbreakable laws of relativity – which gives us a universe limited by the speed of light. It is now, and probably forever shall be the case, that the universe, and we, must play within the bounds of the chessboard discovered by Albert Einstein.
Most of the equipment for the rocket itself can be assembled using today's technology. Providing the fuel, however, becomes problematic. We would require an array of solar powered linear accelerators ('atom smashers') girdling the moon's equator. Mega-engineering projects require, in their own turn, miniature self-replicating factories that draw building materials directly from the lunar soil. Current advances in robot technology teach us that we should be able to climb this technological hurdle by about 2040....
What makes it possible for the realities of scientific achievement (Valkyrie rockets) to catch up with the fiction (starships) is that Valkyrie is the ultralight of rockets, consisting mostly of naked magnetic coils and pods held together by tethers. Indeed, it can best be summed up as a kite (with magnetic field lines instead of paper sheets) that flies through space on a muon wind of its own creation.All of which, of course, is certainly a far remove from, oh, say, the recent mid-term elections, or the latest spins and tantrums of the politically obsessed. But that's the point.