The science fiction writer Isaac Asimov stated on several occasions that George Lucas's galaxy-wide empire bore a close resemblance to the Galaxy depicted in Asimov's Foundation Series. The greatest differences are that Asimov's Galaxy contains no robots or non-human aliens; Asimov addressed both issues directly in the saga's later volumes, most notably Foundation's Edge and Foundation and Earth. Since Asimov's death in 1992, the Star Wars cinematic universe has gained new Asimov-esque elements: Star Wars Episode I: The Phantom Menace introduced the planet Coruscant, which bears a close resemblance to Asimov's Trantor.