Why does the eclipse shadow move across Earth during a solar eclipse?

The eclipse shadow moves across Earth during a solar eclipse because the Moon passes between the Earth and the Sun, casting a shadow on the Earth's surface. As the Earth rotates and the Moon orbits around it, this shadow travels in a specific path, creating the observable phenomenon of a solar eclipse in different locations. The relative positions and motions of the Earth, Moon, and Sun determine the trajectory of the shadow. Thus, the movement of the eclipse shadow is a result of these celestial dynamics.