Every semester I start off my Astronomy classes with the IMAX movie, Cosmic Voyage. It’s a great movie, with a soaring musical score and narration by Morgan Freeman. It covers the scale of the very small, all the way up to the scale of the very large. It shows how our linear thinking breaks down when we deal with such huge changes in the order of magnitude (from the atom at 10^-15m to the edge of the observable universe at 13 billion light years!) People must be able to think in terms of powers of ten, in order to have any grasp on such a huge change in scales. Check out this graphic from xkcd.com that puts it all in a similar perspective for us humans.