Kerr black hole

The ergosphere is an ellipsoidal region around a rotating Kerr black hole in which the hole's rotation drags the spacetime continuum round with it – a phenomenon known as the Lense-Thiring effect or frame dragging – so that frames of reference are not stationary with respect to the rest of the universe. The ergosphere is bounded on the outside by the static or stationary surface, and on the inside by the outer event horizon.


If an object passes from normal space into the ergosphere it can still be ejected from the black hole by gaining energy from the hole's rotation. However, if an object crosses the event horizon, it will be sucked into the black hole and never escape.