It looks like we might finally see what happened to the planet Endor after the Death Star exploded in its orbit. Star Wars: The Rise of Skywalker trailer shows Rey, Finn, BB-8, C-3PO, Dio, Chewie, and Poe as they stare at a massive piece of what looks like the Death Star on an obliterated soil, which could very well be the planet Endor from The Return of the Jedi, which was never shown. Technically, it would be the second Death Star, which exploded at the end of the movie.
The battle of Endor is on the forest moon, which orbited the planet. The second Death Star orbited the moon, thanks to the Imperial base placed on the forest area. After all of these years, we may finally see Endor in The Rise of Skywalker, which from the looks of things, has seen better days. If this is the case, one would have to wonder why the explosion didn't wipe out the forest moon of Endor and all of the Ewoks. Kylo Ren would have surely had to visit the moon to retrieve the charred helmet of Darth Vader.
There are signs pointing to a return to Endor in The Rise of Skywalker. In Rogue One, the Empire was trying to retrieve as much Kyber crystal as they could to construct the Death Star and some have even theorized that the Death Star was just one gigantic Lightsaber weapon. With that being said, maybe Rey needs to go there to get some Kyber crystal for her Lightsaber. This is all speculation, but it certainly looks like she, Finn, and Poe are looking at the wreckage of the Death Star in the trailer.
Chuck Wendig's 2015 novel Aftermath: Life Debt revealed some of the Ewoks had offered their services as therapy creatures to help war heroes, so they are all very much alive and did not get scorched when the Death Star exploded, despite claims by scientists declaring the explosion would have been an Ewok Holocaust. This obviously doesn't mean we are going to definitely see Ewoks in The Rise of Skywalker, but it wouldn't be too surprising if we did, maybe as Rey and crew fly down to Endor in passing.
While this is a pretty big long shot, it does look like Rey, Finn, and Poe are examining pieces of the Death Star in The Rise of Skywalker trailer. We have yet to see the Endor planet and J.J. Abrams could be bringing us there to properly end the Skywalker saga. We still have quite a wait ahead of us, but it is fun to speculate about until then. For now, you can check out The Rise of Skywalker trailer below and see what you think Rey, Poe, BB-8, C-3PO, Dio, Chewie, and Finn are staring at, thanks to the Star Wars YouTube channel. The scene in question is at the 1:38 minute mark.