From By Any Other Name
KIRK: What happened to your ship?
ROJAN: There is an energy barrier at the rim of your galaxy.
KIRK: Yes, I know. We've been there.
Captain's log, stardate 4658.9. With The Enterprise under control of the Kelvans, we are approaching the energy barrier at the edge of our galaxy. Spock and Scotty have devised a suicide plan to stop the Kelvans. They have rigged the ship to explode on my signal.
I'm not in the mood today to combat pretzel logic, and my previous enjoyment of this thread is now plummeting. This episode is clearly talking about the same barrier, and it is established as being at the edge of the galaxy. If that's not clear enough, then—whatever.