The Sphere

A Void Ship is a spacecraft which can be used to explore the Void that exists between alternate universes. Because of this, it is possible for the ship to be removed from time and space.

Until the ship is activated, it appears to have no mass, heat or anything else that allows the ship to be detected except that it is visible and and an invisible barrier prevents anything from touching it.

Currently, the only known Void Ship in existence was used by the Daleks of the Cult of Skaro to escape the Time War with the Genesis Ark. It is unknown if they built it themselves. (DW: Army of Ghosts / Doomsday)