The CA Science Center houses the Space Shuttle Endeavor. The U.S.S. Iowa is a Museum ship in the San Pedro area. It’s one of four of the largest Battleships the USA ever built.
USS Iowa is down in San Pedro. I visited in 2017. However, it totally depends where you are staying. It can be 2 hours drive to anywhere if you don’t know where you’re going.
I don’t want to send you down a rabbit hole, but I grew up in Saugus. My mom worked at magic mountain. It’s now Santa Clarita, but there are many cool places to visit up there. Back in the day, CHiPs, Dukes of Hazard, Knight Rider, Star Trek etc etc. Many shows filmed in that area. Moreso than orange county. An area near and dear to my heart.