[Mentor's note: The thread title has been edited to change the level from "A" to the more appropriate "B"] Suppose there is planet Z revolving around black hole. Astronaut from earth go in that Planet Z and start video recording and make a DVD . Suppose they played that DVD in the computer in that planet . I hope they will feel every clip i that video is normal. But I think when they come to earth and play that video clip , i hope it will be slow motion video isn't it???? i am little confused.. Help me with your answers please.