Continuity mistake: The shards of the goblet Spock breaks change quantity and position on the table with the fruit bowl on it. (00:28:30 - 00:31:30)
Continuity mistake: Just before Parmen starts mind-controlling Kirk, McCoy and Spock, he presents them with three gifts. Kirk receives a large, gold Greek shield, which the captain holds with both hands, in front of him, as the lengthy scene continues. In the wide shot, Kirk is holding the shield high up on his chest, completely obscuring his Federation insignia. In subsequent close-ups, Kirk is holding the shield down low, around waist-level, fully exposing his chest and insignia. Every time the camera cuts back to wide-shot, Kirk is again holding the shield up high on his chest.
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