What Happened To Luke's Green Lightsaber?
Contains spoilers for The Rise of Skywalker
Every Jedi walks a path from apprentice to master, and in that journey has to collect a kyber crystal and forge their own weapon.
In A New Hope and Empire Strikes Back, Luke Skywalker (Mark Hamill) wields the lightsaber his father, Anakin Skywalker (Hayden Christensen), had made during the events of the Star Wars prequel films. Obi-Wan Kenobi (Ewan McGregor) passes the saber on to Luke at the beginning of A New Hope, but the weapon is lost in Cloud City at the end of Empire Strikes Back when Darth Vader cuts Luke's hand off before revealing his true identity as Luke's father.
When Luke returned to the big screen in Return of the Jedi, however, he was seen carrying a new blade. He had finally become a Jedi Master, and in so doing had had to forge his own weapon. This time, Luke's saber burned a bright green, contrasting from the blue blade he had inherited from Anakin. But when the Star Wars sequel trilogy began in 2015 with The Force Awakens, it's Luke's blue lightsaber that Maz Kanata (Lupita Nyong'o) has to the rising Jedi apprentice Rey (Daisy Ridley). Hiding out on a remote island on the planet Ahch-To, Luke is discovered without his second saber. So what happened to the green lightsaber he forged for himself before Return of the Jedi?
It's tricky to tell in the Star Wars films where Luke lost his green lightsaber
For many years, fans believed that Luke lost his green lightsaber at the end of Return of the Jedi when the second Death Star was destroyed. It's a well-founded assumption, given that Luke tossed the saber aside when Emperor Palpatine (Ian McDiarmid) tried to convince him to turn to the dark side shortly before he had to flee for his life from the exploding Death Star. However, when The Last Jedi hit the big screen in 2017, a flashback showed that Luke still had the green blade when he confronted his nephew Kylo Ren, originally known as Ben Solo (Adam Driver), at his Jedi school about the young man's dark-sided tendencies.
So, if Luke still had the green lightsaber in his possession when he was training a new Jedi Order prior to the events of even The Force Awakens, why doesn't he still have it? Unfortunately, there's no official answer given to fans in the films.
Luke never reveals in the Star Wars sequels what he did with the weapon or who else may have it, and at no point does he wield it either. Still, there are a number of possibilities as to the weapon's whereabouts. For one, it could have been destroyed in his battle with Kylo Ren and the destruction of the new Jedi Order. Luke, who opted after that disastrous attempt to reignite the Jedi, may well have destroyed it himself before he went into hiding, or even tossed it into the waters of Ahch-To along with his X-Wing.
A fitting final resting place for Luke's lightsaber
While the Star Wars films may not answer the question of what happened to Luke's green saber, the novelization of The Last Jedi actually does. Author Jason Fry writes in the accompanying novel that the weapon is, in fact, in the possession of the Caretakers on Ahch-To — specifically Alcida-Auka, the matron of the species who looked after the island planet's Jedi village.
Following the fall of the new Jedi Order to Kylo Ren and Luke's self-imposed exile, Luke left a weapon (along with a number of other Jedi relics) with the Caretakers, who placed it in the repository. As Fry wrote in the novelization, "[Alcida-Auka] directed another daughter to take his weapon, his star compass, and his strange other gear to the repository, where it would join other items gathered over the generations."
While it's not outright stated that the "weapon" in question is the green lightsaber Luke forged for himself, it seems like a logical conclusion to assume that it is given that it was the only saber known to be in his possession at the time. It's also a fitting place for the weapon, considering the ancient island is the birthplace of the original Jedi Order.
An old blade for Jedi Master Luke
Luke certainly never used his green lightsaber again. Living in exile on Ahch-To, he would hardly have had much use for it short of slicing toast, and during his duel with Kylo in The Last Jedi at the battle of Crait, he didn't use his green saber. Instead, he used Anakin's old blade, knowing that it would have maximum effect to infuriate his volatile nephew who had always tried to live up to the legacy of Darth Vader (via Movie Web).
Sure enough, seeing his grandfather's blade in the hands of the uncle he so despised was enough to send Kylo Ren into full-on temper tantrum mode again. With Luke becoming one with the Force at the conclusion of that battle after buying the Resistance enough time to escape, he didn't (and wouldn't) wield a lightsaber in his Force ghost form as seen in The Rise of Skywalker, when he confronted Rey about her inner struggle between the light and dark sides of the Force.
Thus, the green lightsaber passes into legend with its wielder, likely resting permanently on Ahch-To.