Atom accelerator

An atom accelerator was a TARDIS component. In the Eleventh Doctor's TARDIS, it was a spiky ball on the navigation panel that spun while in flight and during take-off. According to the Eleventh Doctor, it "steers" the TARDIS. Henry Avery compared it to a wheel amongst other things on the console similar to those on his vessel, the Fancy (DW: The Curse of the Black Spot)