Many Star Wars fans are looking forward to the release of Star Wars: The Last Jedi as it may finally give us some answers about what really happened to Luke Skywalker following the original trilogy. However, there are other sources of information. A new Star Wars novel, The Legends of Luke Skywalker, tells several new stories about the famous Jedi, and one of them, "The Starship Graveyard," implies that Luke Skywalker may have had a part to play in The Battle of Jakku.
The story focuses on an Imperial gunner who, during the battle, slams his head against a control console and sets off a hologram which is essentially an Imperial wanted poster for Luke Skywalker. However, strange things then begin to happen. The Empire falls under heavy attack, and from the gunner's perspective, the blasts seem to be coming from the hologram of Luke.
It should be pointed out that the entire premise behind the book The Legends of Luke Skywalker is that the stories included are just that, legends. The book sees several spaceship crew members, during a time period around Star Wars: The Last Jedi, sitting around and telling stories they've heard about a man they've never met. As author Ken Liu tells Entertainment Weekly, for us Luke Skywalker is a hero, but in the current world of the films, he's more myth than man.
This particular story is even further separated from the actual events as the teller specifically says the story has been passed down from one smuggling crew to another for years. Any story going through that would see minor changes from one version to the next.
Of course, even the most embellished tale had a starting point, and some of the truth of the actual events likely survived. The story would have almost certainly had the more fantastical elements added over time, and so perhaps the truth is much simpler, that Luke Skywalker was fighting at the Battle of Jakku. It would make sense for him to have been there. He was one of the best pilots in the Rebellion and a Jedi Knight to boot. His skills would be incredibly valuable. The Battle of Jakku was the decisive fight that ended the Galactic Empire, there's no reason to believe Luke Skywalker would not have continued the fight until it was over.
Of course, this isn't entirely a semantic argument, as there could be some real value in knowing that Luke Skywalker was there. It's unlikely that whoever left Rey on the planet Jakku years later picked the planet at random. If Luke was somehow involved in Rey being placed there, perhaps this was where he learned the location would be the best choice.
At this point, we don't even know if we'll get all the answers we seek when Star Wars: The Last Jedi arrives in theaters. We'll find out on December 15.