When working on a fairly large sized ship with a large number of turrets, the ship's anti missile turrets will perpetually fire at the same point forever. Even when all missiles have despawned and no enemy ships are nearby all of the anti missile turrets in the area will unceasingly fire at a few points.
Deactivating, resetting, and reactivating the turrets does nothing, as they immediately retarget the same empty space.
Here's a video - https://www.youtube.com/watch?v=iTPAKuMeDFM&feature=youtu.be