According to the show's storyline, as part of an experiment to see how bad movies affected a person's mind, mad scientists Dr. Clayton Forrester and Dr. Laurence Erhardt (aka "The Mads") kidnap Joel, place him on the Satellite of Love, and shoot him into space.
The 11th season of MST3K debuted a revised design for the Satellite of Love, with vertically-oriented "bone" knobs at the forward end of the satellite and horizontally-oriented ones at the rear.