Ceti Alpha Six

Ceti Alpha Six is best known for exploding. This explosion knocked Ceti Alpha Five out of its normal orbit into one that made the already-harsh conditions much much worse for Khan Noonian Singh and his followers.

Ceti Alpha Six exploded when a Section 31 ship crashed into it at the same time that Ronnie Harper, who was on board at the time, ascended into a higher being. ("The Khan Job" [TOS])