Hubble witnessed the collision of Comet Shoemaker-Levy 9 with Jupiter in 1994. This is a composite photo assembled from separate images of Jupiter and the comet. The comet had broken up into at least 21 separate fragments. When fragment G struck Jupiter, the impact created a giant dark spot roughly the same diameter as the Earth and was estimated to have released an energy equivalent to 6,000,000 megatons of TNT (600X the world’s nuclear arsenal).
SMOD and then some.
Image Credit: NASA