How close do you have to be from a black hole to experience noticeable time dilation. I always believed you will not experience noticeable dilation until you are at or in the event horizon is this correct? Also does rotation/spin of mass such as a planet decrease it's inherent gravitational pull? I understand that at the surface an object will experience centrifugal force from spin, but what about object orbiting a mass? It should not have any effect, correct? Interstellar the film suggested there could be habitable planet experiencing time dilation due to the distance from a black hole, logically I would assume any planet experiencing noticeable (such 1 to 5 hours) time dilation could not exist because it would eventually fall into the black hole is this correct?