How long would it take humans to reach the closest star? Would we be able to send astronauts to explore it? If someone journeyed to another solar system, would she ever see Earth again? The distances between stars are mind-bogglingly big. In sci-fi movies, space ships are able to jump between stars in an instant. In real life, space travel takes a lot longer.
Our Farthest Voyage
Voyager 1 is the fastest space object we’ve ever built. However, some scientists believe it could be possible to create nuclear-powered space ships capable of traveling at half the speed of light. It would take them only 89 years to reach Proxima Centauri. That means that only a couple of generations of humans would have to spend their lives hurtling through space. Unfortunately, we can’t build or test these ships. International law forbids the dumping of nuclear waste in space, and a nuclear-powered ship would leave a trail of waste behind it. Unless we find a new way to power space ships, we might be stuck in this solar system forever.
See for yourself: http://www.abc.net.au/catalyst/stories/3785366.htm
Check out the links below to learn more about interstellar travel and the possibility of space colonization by humans.