The Sphere
A Void Ship is a spacecraft designed to explore the Void that exists between dimensions. It appears as a golden sphere until it is activated, at which point it opens up to reveal the occupants. There is no evidence that the ship can actually touch it's surroundings.
When travelling through the Void, it is separate from time and space and, until activated, has no detectable mass, heat or radiation, though it is visible. An invisible barrier prevents anything from touching the ship.
It was thought to be impossible, but it did exist. The only known Void Ship 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 or if it was constructed for them. (DW: Army of Ghosts / Doomsday)
