Remote Ship Issue

Doing a play thru on Mar's. My one rule is i can not go into space making me rely on antennas and relays with remote piloting ships.My issue is i have been out 190km with a remote ship looking thru the camera and no Asteroids spawned. As i got fed up before i restarted the map. I then broke my rule and went into space. Of course the asteroids started spawning as soon as i was about 80km out.
My issue is are asteroids only able to spawn within a physical distance of the player?
Can a remote ship not spawn them in?
I would hate to have to change the play thru, because once i go into space i know the game is basically won.

So I marked my location with asteroids, and RTB'd. I then remote flew my miner to the location and no asteroids where present.