Need suggestions to tighten asteroid type game

I would appreciate the wisdom of the group on two items...

1. Smoother animation of the asteroids? Seems too jerky, and I suspect if I used a different method, I might get smoother motion.

2. I seem to have a bug somewhere in my world.Blaster method, where my laser randomly fires at asteroids....good for saving the earth, not so good for working as expected...

Can anyone suggest improvements?

Thanks!

brian