The Chandler wobble is the change in the spin of the earth on its axis. Think of the wobble you see in a toy top when it first starts spinning or slows down. Its "poles" do not spin in a perfectly straight line.
If I was on the moon and the earth was black (no lights were on) and a flashlight was turned on facing the moon, would I see the light? If I couldn't, would there be any way to detect any residual matter that came from the light on Earth or does light die after a certain distance?