Answer:
You didn't give any image, but if it's celestial, I think that maybe something sacred: an angel manifestation, a light bean descending over a person, something floating near someone to express religiosity... the answer is wide, and can be several things.
Step-by-step explanation:
By tradition, celestial objects are portrayed in images surrounding by an aura, almost transparent, and highlighted with some trick of perspective. And to show the religiosity, they are traditionally represented closer to sacred things such as a crucifix, or churches, or saints.