June 29, 2007
ET Phone Home
A while back there was a piece about how colonizing space is not really feasible. Distances are too great. But now there's a piece about how even contact with extraterrestrials is inadvisable. I think the former article makes the latter irrelevant.
If a message we recently beamed towards M13 will take approximately 25,000 years to get there. If anyone on the other end responds immediately, we won't find about about it until about AD 52,000, assuming there's still anyone around at that point.
But let's say there's someone in our immediate galactic neighborhood, say within 200LY. It'd still take 400 years for a round trip radio message, so we're looking at sometime around AD 2400. But what if instead of sending a reply they immediately launched a fleet of conquest? That probably won't get here for at least 4,000 years, and that's assuming they can achieve .1c pretty quickly. This, as established in the first link above, is really, really hard.
But what if they can travel faster than light? If they can do that, it doesn't really seem to matter whether or not they're friendly. We're toast either way. Breaking that barrier is theoretically possible, but all of the current exceptions involve such massive expenditures of energy that any culture capable of doing it would be so far ahead of us that we'd either be entirely uninteresting or the matter of a quick morning's conquest.
Eventually, it's all probably moot. We've been broadcasting radio into space for about sixty years, and the broadcast of specific intentional messages will more than likely get lost in the static. The sphere of space which is more-or-less saturated by terran radio signals is currently 120LY across.
Unless we have massive increases in our ability to produce and harness energy, space will never be a viable frontier. I'm in favor of occupying near-Earth orbits, the LaGrange points, and the moon, but anything else is probably just a bridge too far.
