Gravity bubble

A gravity bubble was a form of technology that allowed an object to beat the boundaries of gravity and travel in space.

Milo and Frank Shakespeare used gravity bubble technology to transport a Nukaryote to the fathership in space. (DWM: Doctor Who and the Nightmare Game)

Edwin Bracewell applied this technology to Spitfires, allowing the pilots to travel around the orbit of planet Earth and attack the Dalek Saucer. (DW: Victory of the Daleks)

Silurians used this technology to transport themselves from their civilization to the surface of Earth. (DW: Cold Blood)