Question: What exactly are gravitational waves, and how do they arise? Why are there different frequencies, and what about the object producing the waves determines these frequencies - is it related to the mass of the object, or does this only affect the amplitude? How, and why, is it possible to locate where the waves originated from - do they vary over distance in a predictable way? Can we tell from experiment the direction a wave has come from, or two opposite directions it comes from, by looking at the effect of the waves on coherent light? How strong are these gravitational waves - wouldn't they need to be quite strong to bend light, or is the effect they have not the same as gravitational lensing? Thank you!