How to calculate an intercept course?

Hi all, I’ve been trying to crack this problem for more than two days now, and it’s starting to frustrate me.

Here’s the situation. I’m working on a game which will involve space battles, and automated turrets. The turrets are giving me the headache right now. Here’s what I got so far.

The problem is, that the turrets aim at the center of their target, instead of aiming in front of their target to compensate for their movement. I can’t seem to crack the equations needed to get the right rotation, for the turret to fire from.

The data the turret has avaible, or that I could easily make avaible to it, are:

  • The distance to the target (and it’s x and y components)
  • The current speed vector (the size and rotation)
  • The angle between the heading of the target and the turret’s location
  • The speed of the turret’s shot (fixed speed)

If anyone here could help, I’d much aprecciate it!