Correct me if I'm wrong, please. If I travel at near the speed of light in my new spaceship then an observer here on earth would age 20 years while I'd only age a small fraction of that. I understand that (well, I believe that). Here's where I start running into questions. The observer on earth watches me go 20 light years from earth. If I just went 20 light years from earth and only felt a small amount of time pass doesn't that bring the problem of traveling to other stars down to the "simple" problem of engine power? I read once that some guy didn't think humans would ever go to another star system because of the huge travel times needed, but if I'm understanding relativity if I'm willing to cut myself off from the rest of the world and have a fast enough ship the entire universe is accessible. Even though I never go faster than light.