Halley's Comet

Halley's Comet was a comet of the sol system and one of the few that could be seen by the naked eye. However, it was only visible in this way when it approached Earth every 75 to 76 years.

Its frequency and easy visibility made it one of the better known comets in the Sol system. On Earth, Halley's Comet was associated with impending disaster.

Time traveling to 1985, the Cybermen planned to divert Halley's Comet so that it would destroy Earth. This way, the Cyberman home planet of Mondas would not be destroyed when it approached Earth in 1986. The plan was foiled by the Sixth Doctor. (DW: Attack of the Cybermen)