A particle's velocity to an arch

I have created a ParticleSystem that spawns one particle every second, and that particle has a sub emission of another particle system, witch create a sort of a trail. My problem is how can I change the velocity of the main particle so that it goes in the direction that originally comes from, in a circle. Here is a picture of what I want to do:

![alt text][1]

The green line shows how i want the particle to travel, like a Sun eruption.

I maneged to find how to edit the particles but how can I make a path like that?

    function LateUpdate(){
	particlesCount = ParticleObject.GetParticles(Particles);
	var i:int = 0;
	
	while(i <particlesCount){
		Particles*.velocity =;*
  •  i++;*
    
  • }*

  • ParticleObject.SetParticles(Particles,particlesCount);*

}
[1]: http://dl.dropbox.com/u/63103279/Images/Untitled.png

To have it get “pulled” back into the sun, compute the direction to the sun, and give a little push that way:

Vector3 sundir = (sun.position - P*.position).normalized;*

P_.velocity += sundirTime.deltaTime10; // 10 is the “pull” of the sun_
This same code works for homing missiles.