This is a question about electromagnetic waves and gravitational waves. Let's say we're on the Earth and we're looking up at the sun (safely). If the sun were --for some reason-- to violently and dramatically jerk from its position, how would we first find out? Would we first *see* the sun move? Or would we first detect a change in our orbit? Would the light, the electromagnetic wave, reach us first, or would the gravitational wave reach us first? Would they happen at the same time?