- You may be looking for the ship.
A comet was a ball of ice and rock that existed in space. When their orbit took them close to a star, the solar winds melted the ice and formed a tail behind it. Many comets existed in the Oort cloud. (AUDIO: Murmurs of Earth)
Halley's Comet was one of the best-known comets in Earth history. Its orbit brought it close to Earth approximately every seventy-five years. It collided with a Persopolisian ship in 1066. (AUDIO: The Time Capsule) The Cybermen time travelled to 1985, planning to divert Halley's Comet to crash into Earth, thus preventing the destruction of their home planet Mondas the following year. The plan was foiled by the Sixth Doctor. (TV: Attack of the Cybermen)