“An existence equal to that of ‘La persona superiore a Dio’.  If necessary, it can give off an explosion to make a star vanish into nothingness, and undoubtedly erase the anchor in front of him that has lost its purpose in life.”
(Toaru Majutsu no Index Volume 22, pg 49)

“The giant spiral of light released by Fiamma was slashed in half vertically, and spread towards the left and right side of the boy. Even if this power is one that can erase a burning star into nothingness and the ultimate power that has risen once again from the myths of Christianity.”
(Toaru Majutsu no Index Volume 22, pg 50)

There are two translations of these quotes. The word used is hoshi (星), which by itself means star or any light emitting heavenly body. Words regarding “Celestial Bodies” using hoshi generally can be translated to several things, from planets to stars. In a lot of cases there is no distinction between the two in a japanese.