I was browsing through YouTube and I came across this video of Space Mountain that was in a phase of failure that for whatever required the main lights to be turned on. It’s a unique view of the ride that you’re likely never to see unless you’re a Disneyland cast member or ride mechanic.
Here’s another interesting video of Space Mountain where apparently the rocket weighed too much so it had to be emptied in the backstage area. This area can be slightly seen when you’re leaving the station and your rocket turns right to go up the climb. If you look left, you can see this room (although mostly blocked from view).