I think they should be able to detect it all right. There should be no \"Built-in\" advantages. The advantage of having a place as your base is that it is yours. You OWN the place. They may see your base, but not your fleet of stealth mines, nor your massive doom turret, nor recognize that that asteroid has missiles locking on to it. That is the tactical advantage of having a place as your base. And by the time the next wave arrives, you know that they are coming. (Put an AI module and weapons inside an asteroid. Like a boss.)