Folks, I'm in the process of trying to understand spacetime curvature in general relativity. My question might sound odd, but I'm wondering how to best conceptualize spacetime distortions due to a moving mass. If there is a large mass, e.g. a planet, moving through spacetime, the curvature will change. Does spacetime 'stretch' with the change in curvature? Or does it 'grow', i.e. is there somehow an increase in the 'amount' of spacetime in one region as the mass moves, and a corresponding contraction in region the mass previous occupied? (if that makes any sense) Or am I completely off track? Thanks all.