Artistic depiction of a Bussard Ramjet, a proposed spacecraft thruster that could accelerate an interstellar spacecraft to a very, very high speed.

Interstellar space travel is manned or unmanned travel between stars. Interstellar travel is much more difficult than travel within the Solar System, though travel in starships is a staple of science fiction. Actually, there is no suitable technology at present. However, the idea of a probe with an ion engine has been studied. The energy would come through a laser base station.