It is an inescapable fact. The destinations we can visit in outer space will always be limited by the technical challenges of travelling the unimaginable distances involved, especially within a human lifespan. Still, that will not be the only factor shaping where our descendants go. The route that they take into the cosmos will be equally driven by age-old human motivations - and perhaps even a dash of religious fervour.
First, the bad news. Last year, a group of scientists, engineers and futurists assembled in Orlando, Florida, to plot humanity's next era of exploration. The name of the plan was the 100 Year Starship Study. The idea was to begin to work out, over the next century, how to get humans to the nearest stars. You can't fault the idea for ambition, but many of them soon realised that developing the necessary technology was daunting, if not fanciful.
Neal Pellis of the Universities Space Research Association based in Columbia, Maryland, summed up just how far our fastest spacecraft are from achieving interstellar travel. "The nearest star is Alpha Centauri," he told the 100 Year Starship meeting's participants. "At 25,000 miles per hour, it would take 115,000 years to get there. So this is not a plan."
Obviously, 25,000 miles per hour is ridiculously too slow. Propulsion science needs to go much further than that. To read more, click here.