Interplanetary transport refers to the transportation of people or objects between planets. The most common forms of interplanetary transport are spaceships and UFOs. Spaceships are large, man-made vessels that are designed to travel through space and are typically powered by some form of propulsion system. UFOs, on the other hand, are unidentified flying objects that are believed to be of extraterrestrial origin. They are often seen as mysterious and unexplained phenomena.