Hello, I'm newbie to physics and relativity and I wish to know more. I've had a question for 5 years and nobody has been able to give me a clear answer. Here it goes! Suppose there were 2 astronauts in space one in front of the other. There is a distance of one light year between them. Both are grabbing a pipe, or whatever solid object, which is also one light year large.(assuming that were technically possible to create an object that large...).What woud happen if one of them pushed this "pipe"? (and of course were strong enough to move it...). When would the other astronaut feel this push? a year later, instantaneously? Regards and thank you for your answers!