I've been doing a fair bit of mining but one thing about the process is confusing me a little. When I enter a system and warp over to an Asteroid Belt, many times there is simply nothing present at that location. Now, I know that mining an asteroid will eventually result in it disappearing once it has no more ore left to give, so obviously in these cases the entire belt has been mined and there's nothing left.
My question is, how can I find out which asteroid belts in a system has ore left to mine without visiting every single belt in the system? Is this even possible?