It helps to have a fair understanding of the size of things. Everything is relative, after all. Powers of Ten The first is a video called The Powers of Ten. It's old, but not as old as the concepts. With this 9-minute video you can appreciate just how much space there is between all the things. The Scale of the Universe The second is a nice little interactive app by Cary Huang that lets you drag a slider to zoom in and out of the size of things. Like the Powers of Ten it can take you from the most macro to the most micro: Observable Universe (in Pictures) And lastly: 26 Pictures Will Make You Re-Evaluate Your Entire Existence .