AAA now comes with a new feature: manual name overrides! Admins can now override the random name generation, and assign names to star systems manually.
To assign a name to a star system, use the command: /set_system_name x y z <NAME>
e.g. /set_system_name 0 0 0 Origin
To clear an assigned name and return to the default, use: /clear_system_name x y z
You can also run these commands without supplying coordinates, and the mod will default to the system you are currently in as a player.
Unfortunately, spaces in custom names cannot be assigned via the command at this time (17 Oct. 2020), pending Starloader changes to custom command creation. However, as Starloader automatically patches itself on startup (currently), you may boot up the game one day to find that this works just fine! For the time being, the workaround is to assign a placeholder name, then open the .yml file for your world under /moddata/AwfulAstronomicalAppellations, and then manually edit the name value for the system you want to give a name containing a space.
In the future, I will likely create a separate mod that allows players to rename their faction's claimed systems by a similar method.