The Webstar was the spacecraft of the Racnoss. It resembled an eight-pointed star made of a silk-like substance. Powered by Huon energy, the Webstar was equipped with teleport technology and could fire lightning-like bolts of energy from its points. (TV: The Runaway Bride) A single Webstar was capable of destroying several cities. (AUDIO: Empire of the Racnoss)
Ultimately, the Webstars were reduced to only one, the Empress' personal Webstar, which travelled to Earth in 2007 when she detected that the Secret Heart had been uncovered. The ship served as her base as she plotted to awaken her children by creating Huon particles. After this plan was foiled by the Tenth Doctor and Donna Noble, she returned to the Webstar intent on devastating Earth.
However, the Empress had exhausted her supply of Huon particles, leaving the Webstar defenceless. As the ship descended upon London on Christmas Eve, it was fired upon and destroyed by British Army tanks by order of Defence Minister Harold Saxon. (TV: The Runaway Bride)
Saxon mentioned the Webstar and the death and destruction it caused in his address to the British people concerning the Toclafane. He referred to it as the "Christmas star that came to kill". (TV: The Sound of Drums)