I think the dilema of travelling to distant galaxies will only be overcome by the use of a combination of technologies. viz,cryonics and time-travel.Let me explain.
An astronaut is put INTO cryonic suspension and despatched INTO space to a particular destination.It may take hundreds of years to get there, but on reaching his destination he then completes whatever tasks he was sent to do puts himself back INTO deep sleep and travels back to earth. By the time he gets back though, hundreds of years have passed.So now he makes use of time-travel, thus returning to the exact date of his departure, albeit with the information he was send to obtain. For his masters it would seem as if the journey was instantaneous, since the date of departure has(through the use of time-travel)been made to be also the date of arrival. Thus we would have at our disposal......instantaneous travel. The astronaut would naturally not have age much since cryonic technology would have all but eliminated the normal aging processes during the journey. This I believe is the only way we will ever be able to explore the galaxy. So space travel and time-travel are inextricably linked together. We solve the time-travel problem we solve the space travel problem.
