Outra explicação:
Originally, the color of Luke's new lightsaber was blue, the same as the one he lost in Star Wars: Episode V - The Empire Strikes Back (1980). Luke can even be seen wielding a blue lightsaber in early ROTJ trailers. However, when a scene of Luke assembling and activating his new saber was cut, George Lucas thought the audience might not understand that Luke's ROTJ lightsaber was not the same one he lost on Cloud City. To avoid confusion, Lucas decided to change the color from blue to green, making it clear that Luke was using a new saber. (As part of the Expanded Universe -Legends-, Luke's original lightsaber, used by his father and given to him by Obi-Wan, was recovered (along with his severed hand) from Cloud City and was later wielded by a Luke clone. Luke later recaptured this saber and presented it to Mara Jade, his love.)
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