When flying above clouds on can frequently find the shadow of the aircraft they are riding in. As the aircraft approaches the cloud the observer will note a halo, known as a Glory, surrounding the shadow . If the aircraft gets close enough to it's shadow one will see the Glory is centered on the observer's position in the aircraft. I took this phot from the cockpit of a 727 flying in and out of the cloud tops on a flight from DCA to JFK. (1996)