Galileo discovered in 15th century that any object falling to earth ,falls at the same rate of acceleration.
He mentioned that a cannon ball and feather if dropped from the same height , will touch the ground at the same time, in the absence of air resistance. He found it difficult to explain it.
Four centuries later with the current technology, watch as Brian Cox travels to the world’s biggest vacuum chamber at NASA’s space power facility, Ohio to experimentally demonstrate the theory.
It is a visual treat to watch this video.