This interactive java tutorial is a version of the renowned Powers of Ten film I first saw at the Smithsonian decades ago. In successive jumps of an order of magnitude apiece, you travel between a 10^-16-meter view of the quark-texture of subatomic matter and a view of our galaxy from 10²³-meters (10 million light years). Show it to your scale-challenged friends.

They could go further out. At least three further order-of-magnitude steps up are possible, as current thinking suggests the furthest objects are quasars somewhere over 10 billion light years distant. Are these extra steps not included because there is nothing interesting to be revealed at views of those scales? Recent discoveries suggest that there is a ‘coarse structure’ to the clumping of galaxies in the universe as a whole. Is that as far as you can go? Beyond 10-15 billion light years, by current estimation, you exceed the distance light could have travelled since the origin of the universe; given that speed limit, you run out of size there. Step out further and you arrive at…what? The face of God, most likely. Which, by the way, is waiting for you at the other end of the spectrum in the smiling visage of each quark as well, right? as you run out of size at the bottom end? [thanks, nathalie]