Newton's theorem of revolving orbits does not go to infinity. However, this conclusion holds only when two bodies are present (the two-body problem); the motion of three bodies or more acting under their mutual gravitation (the "n"-body problem) remained unsolved for centuries after Newton, although solutions to a few special cases were discovered. Newton proposed that the orbits of planets about the Sun are largely elliptical because the Sun's gravitation is dominant; to first approximation, the presence of the other planets can be ignored. By analogy, the elliptical orbit of the Moon about the Earth was dominated by the Earth's gravity; to first approximation, the
Three Laws of Robotics Three Laws. However, the 1960s German TV series "Raumpatrouille – Die phantastischen Abenteuer des Raumschiffes Orion" ("Space Patrol – the Fantastic Adventures of Space Ship Orion") bases episode three titled ""Hüter des Gesetzes"" ("Guardians of the Law") on Asimov's Three Laws without mentioning the source. References to the Three Laws have appeared in popular music ("Robot" from Hawkwind's 1979 album "PXR5"), cinema ("Repo Man", "Aliens", ""), cartoon series ("The Simpsons"), tabletop roleplaying games (Paranoia) and webcomics ("Piled Higher and Deeper" and "Freefall"). Robby the Robot in "Forbidden Planet" (1956) has a hierarchical command structure which keeps him from harming humans,