You also have the option of using a macro for that and other ground target actions. It will activate on the first press, centered on the specified macro target. This is slightly faster than placing the circle manually, at the cost of precision.

Ex.:
Code:
/ac "Earthly Star" <mo>
/ac "Earthly Star"
/micon "Earthly Star"
Will center an Earthly Star on mouseover target. If no mouseover target available, will provide the ground target circle for manual placement.