Place dots on the circle like so:
x = Position + Radius * cos(Angle)
y = Position + Radius * sin(Angle)
Position will be the center of the circle (your player ship)
Radius is the size of the circle
Angle will be the angle between the circle and the missile. To get that, use angle(x1,y1,x2,y2)
When a missile is created, create a dot and give it a variable with the UID of the missile. Then use "pick by unique ID" to pair them. You can probably use a container instead if you want.
The size of the dots can be based on the distance between the dot and the missile using distance() and...er...range conversion, maybe. Using just distance() will make them smaller as the missiles get closer.
Hope that helps.