Light spots and shadows If a laser beam is swept across a distant object, the spot of laser light can seem to move across the object at a speed greater than c. Similarly, a shadow projected onto a distant object seems to move across the object faster than c. In neither case does the light travel from the source to the object faster than c, nor does any information travel faster than light. No object is moving in these examples. For comparison, consider water squirting out of a garden hose as it is swung side to side: water does not instantly follow the direction of the hose.
light spots and shadows if a laser beam is swept across a distant object the spot of laser light can seem to move across the object at a speed greater than c similarly a shadow projected onto a distant object seems to move across the object faster than c in neither case does the light travel from the source to the object faster than c nor does any information travel faster than light no object is moving in these examples for comparison consider water squirting out of a garden hose as it is swung side to side water does not instantly follow the direction of the hose