The speed of light is about 670,616,629 mph, and one could travel round the earth 7 1/2 times in just a second with this speed. For another perspective, the average distance from the Earth to the Moon is 238,854 miles, and light travels this distance in just one second.
Scientists determine the speed of light using the metric system and state that light moves 299,792,458 meters each second. The average distance from the earth?s surface to the sun is approximately 149 million kilometers, and the sun's light requires about 8 minutes to reach the earth?s surface. In 1676, Ole R?mer became the first scientist to perform studies estimating the speed of light.