Creating new systems on the go (or activating existing jumpgates)

[Wilmore]

Would it be possible as a part of a quest chain, to generate a new station or system (like "fixing" a jumpgate or something like that). That would be epic!

[ai_enabled]

It might be possible as the generation scripting API allows spawning new objects at any time.
However, I'm afraid that the new jumpgate will not work as the routes are cached after the galaxy generation or after the savegame loading. If a new jumpgate spawned the cache should be invalidated but, as we didn't have such need during the game development, I can't say for sure.
Also, it's impossible to remove the star system so it might become a problem as more and more systems spawned during the gameplay.

[Wilmore]

I was thinking this more as a part of a mission chain, not as the universe continuously expanding. Would it work with a jumpgate then?

[ai_enabled]

Jumpgate can have a pass condition. That's used to ensure that player doesn't leave the starting system before finishing the first quest and also that player cannot enter Alien systems early. Perhaps that will suffice for your idea?
Of course, the discovery of a completely new star system sounds much more interesting than simply unlocking a jumpgate to another system, but considering that the game architecture was written for one-time world generation it's much easier to achieve by using the already proven game API...