Electrons can be found at any point around the proton/neutron nucleus. They do not circle the nucleus as once taught. If humans ever want true deep space travel, we hsve to figure out how electrons move. The nearest star from Earth is about 4.6 lights years. That is over 9 years roundtrip at light speed. The other side of the galaxy would be 100,000 years of travel, one way. Even at light speed, space travel is not feasible. Light speed would be fine for exploring our Solar System only.