Lucas continued to hone his script, aided by screenwriters Willard Huyck and Gloria Katz; names of planets and characters were revised and the narrative was improved, and by the fourth draft, scenes on the Imperial capital planet had been moved to a space station called the Death Star and the name of Alderaan was now given to a peaceful world destroyed by the Empire. The Empire's homeworld, Had Abaddon, came up in early drafts of "Star Wars: Episode VI - Return of the Jedi". The entire planet was to be a sprawling city. However, concluding that the realization of such a city was impossible at the time, the creators abandoned the idea. Later, in the graphic novel "Legacy 29: Vector, Part 10" the name Had Abbadon was given to a lost mythic planet in the Had Abbadon System of the Deep Core, which was covered by dry fields, was linked to the birth of the Jedi, was the location of a planned assassination attempt by Cade Skywalker on Darth Krayt, and was home to an Imperial. The Empire's homeworld first appeared in the expanded universe and was called Coruscant for the first time in Timothy Zahn's "Heir to the Empire". Coruscant was first seen on screen in the 1997 Special Edition release of "Return of the Jedi", and the "" series of computer games. Coruscant was then seen (major appearance) in "". There is a speeder chase through the skies of Coruscant in "" that eventually leads to a nightclub in the bowels of Coruscant's Uscru Entertainment District. Coruscant is seen in "" as part of the opening battle scene. The planet's cityscape is then prominently featured throughout much of the movie, with Chancellor Palpatine's office as well as the Senate building being the primary two settings on Coruscant. In various novels, characters aligned with the Empire refer to Coruscant as "Imperial Center". Within the stories, this is explained as an administrative renaming undertaken to emphasize the differences between the Old Republic and the Empire. Coruscant was in some early sources called "Jhantor" in homage to Isaac Asimov's Trantor. Production artwork produced by Ralph McQuarrie for "Return of the Jedi" had included some unrealised designs for the imperial capital, Had Abaddon. During production of "The Phantom Menace", it was decided that scenes would be set on the capital planet, now called Coruscant, and artist Doug Chiang was tasked with designing the imperial city, and he turned to McQuarrie's original concept art.