Complex sentence: Finally, they wanted to eliminate the large dumbbell-shaped star projector used in traditional planetariums, which juts from the center of the room and blocks part of the view, and would also interfere with the movies being projected onto the dome.
Split into simpler sentences: Finally, they wanted to eliminate the large dumbbell-shaped star projector jutting from the center of the room and blocking part of the view. Such a star projector would also interfere with the movies being projected onto the dome.