Space Seed - S1-E23
Visible crew/equipment: When the landing party are aboard the Botany Bay talking about it being a sleeper ship, Kirk asks if it's possible they're still alive, and as the camera follows Kirk the shadow of the camera/cameraman is visible on the wall, at the right side of the screen. (00:06:25)
Space Seed - S1-E23
Visible crew/equipment: When Khan hides behind the wall in the engine room before Kirk enters, a crew member walks in front of the stage light and you can see the shadow of his head passing across the floor.
Chosen answer: If they're in orbit, they're being pulled along by the planet's gravity well, therefore, impulse engines would only be used for minor corrections and would be "on standby" while in orbit, but not active. (Like keeping your car idling without revving the engine and creating plumes of exhaust).
Captain Defenestrator
Thank you for the info.
Movie Nut