You don't worry about that, any engine will do.
What you do is use your own coordinate system.
I use a 64 bit integer for each coordinate, then when you actually want to display something you call a method on the coordinate class which returns a 3d vector or null. In this method you subtract the camera's location from the object's location and check if the result fit's in a 32 bit float. If not, return null.
If it is null, then the object you are trying to render is beyond visible range.
Using this system you can map more space than you could explore in a lifetime on any engine, and if that isn't enough for you, swap to 128 bit int's
There is a freeware space exploration thing out there that uses this system, can't remember the name of it at the moment, someone here will though.