Flapping Bat Shadow Video

This video shows the "flapping" of the Bat Shadow's wings. This motion is most likely caused by the shadow of a saddle-shaped disk, with two peaks and two dips. The disk must also be flared, like bell-bottom pants or a trumpet. The shadow is so large—about 200 times the length of our solar system—that light doesn't travel instantaneously across it. In fact, the time it takes for the light to travel from the star out to the perceivable edge of the shadow is about 40 to 45 days.