Star Control

Star Control is a side quest in the Fallout 4 add-on Nuka-World.

Detailed walkthrough
Upon approaching the Galactic Zone, the player will notice a large amount of corpses and destroyed robots lying around outside the entrance. One of the bodies is that of Tiana, who has a holotape on her. Read the tape to prompt the finding of the Star control mainframe, located at Starport Nuka near the center of the zone.

Once through its glass door, (after admiring that Quantum X-01 armor) the back wall has the mainframe. It requires a Star core to boot up, which can be found in the hand of the nearby corpse of Kendell Alston. Affix the core to one of the many empty panels surrounding the mainframe to activate it. From here you will be required to locate the remainder of the Star cores. There are 35 in total, including the one Kendall was holding. For the cores in the Galactic Zone, having three tiers in the Lockpick perk will help, but keys can be easily found.

In the Starlight Interstellar Theater, one core can be located on a panel through the theater's pantry, down the corridor to the right of the entrance. The key to the door is on the kitchen counter. A second one is located down the opposite corridor to the left of the entrance, in a hole in the wall of the bathroom. The third is located in the centre booth of the theater room itself, guarded by sentry bot Startender. The fourth is upstairs, powering the projector.

In the RobCo Battlezone, one core is on the lower level to the right when facing the stairs, in the store section behind the checkout desk. Be sure to pick up the Nuka-Ray recipe book on the shelf. Two more cores are located in the arena; entering it will cause the doors to lock, releasing robots into the room. Another core is beneath the arena, down a staircase to the side of the arena's entrance. The final two cores are above the entrance, accessed by the keys that are under the arena or on a table near the arena entrance.

In Nuka-Galaxy, the first core is located to the left and downstairs, in a small mainframe room attached to the ride's loading bay before the start of the ride. The others must be retrieved by following the maintenance route beneath the coaster's track. The first of these is at the bottom of the asteroid room. From here, an elevator must be taken down (or else hop on the track and run down) to where alien animatronics are fighting a Space-sentry, where the next core is located. Another is found near the entrance to the UFO room where the track coils around a planet. The next core is located at the end of the ride, where the Nuka-Girl outfit is obtained. After picking up the key on the desk next to the core, the employee-only door can be opened, where another two cores wait.

The last building is Vault-Tec: Among the Stars. The first core is in the first exhibit in a locked door behind the rocks. Another is behind an Expert-locked door off the side of the home-suite exhibit. The home-suite has a broken wall, and the room beyond has another core. The last three are in the control room.

With at least 20 cores in hand, install them into the mainframe's ports. Once all of them are in, the rogue robots can be taken off defense mode.

Further cores
It's best to look for these at night, where their distinctive orange glow makes them easier to spot. There are 12 remaining if the above 23 are picked up.
 * Behind the Starport where the traders were camped out, through a door to a dead end room with a powerloader in it. The core is next to a dead trader. (south of starport is a Nuka-Cooler recipe book)
 * Directly above Starport - can be reached via the ramp to the entrance of the Vault-Tec building - in an advanced-lock display. The key is through a novice-lock door.
 * The elevator requires the main power to be restored, but another core is at the top of the tower.
 * To the right of Nuka-Galaxy's door in an operation booth.
 * Across from the Nuka Galaxy's operation booth is the "Arc Jet G-Force ride". At the top of the ride is a core.
 * At the bottom of the ramp by the exit door of the RobCo Battlezone.
 * To the south of The Giddyup Kid at Dry Rock Gulch.
 * In the shed at the Nuka-World junkyard on the second level next to SCAV #2. Can be found more easily during the hubologist miscellaneous questline. Othwerwise the junkyard is southwest of Vault-Tec: Among the Stars outside of the Galatic Zone. Oddly enough this area can reset allowing you to gain another star core.
 * On a workbench in the back room of the Nuka-Cade
 * In the Nuka-Town market, on a table to the left of the vendor Shelbie Chase
 * in the Nuka-Cola bottling plant near the back next to a large glowing blue container, and Sergeant Lanier (deceased).