Continuity mistake: The landing party beams down in daylight, but the window inside Mendez's office shows that it's night outside. In the next exterior shot, it's day again. Next shot back in the office: night. (00:00:30 - 00:05:20)
Continuity mistake: Kirk introduced Spock as "Lieutenant Commander" instead of "Commander".
Other mistake: While on Starbase 11, Kirk and McCoy watch Pike on a starbase desktop monitor as his light keeps blinking no. When Kirk is with Mendez in his office discussing the Talos IV top secret file, Piper watches Pike on the desktop monitor in the office. Then Spock uses the monitor in his quarters to watch Kirk. All these monitors have the same dings and markings around their screens, which are also the same as other desktop monitors on Enterprise in the previous episode, The Corbomite Maneuver. (00:11:10)
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