The fastest space craft (Helios I & II Solar Probes) travel at 252,792 km/h. 20.5 Lightyears / 252,792km = 767,195, 292 (hours it will take to get there) 767,195, 292 / 8,765.81277 (hours in a year) = 87,251.2958 years to that planet. I don't know where some of you are getting your math from.