Thanks, spoonsweet! I'm glad you liked it.
I think you lucked into when the asteroids spawned. I had it set so that when they're first created the asteroid can't harm you for like, 90 frames or something. I did that mostly so if you were using screen wrap movement you wouldn't get hit by an asteroid just spawning, but I didn't realize until after that when you destroy a rock it creates the new ones and they can't harm you until after that same time frame. I left it in because I figure Asteroids is already frustrating enough!