If you were on the moon looking at the earth, why can you not see light between the earth and the sun? Same goes for heat. Why is the space between the sun and the earth so cold. Does light and heat only exist once it interacts with something else? If light is a particle wouldnt the particles spread out to the point where you would have no idea what of where an object is. If light is a wave wouldn't we see sunlight cover everytinhg in every direction?