It is difficult for us to fathom the scale of the universe. The differences between the smallest structures and the largest are so enormous that linear scales are useless. We need exponential scales, which make the numbers appear to be easy, even when the geometry is simply incomprehensible. A simple example can demonstrate these size differences – there are more atoms in a glass of water than there are glasses of water in all the oceans combined. (If you don’t believe it, here is the math.)

On an exponential scale in meters, humans are located at the midpoint between the nanometer scale (1×10−9 m) (a strand of DNA is 3 nanometers thick) and the scale of stars ( the sun is 1.4 ×109 m in diameter.) Reaching “down”, what we try to do in nanotechnology, is just as difficult as reaching “up,” exploring the solar system with our probes. But, the journey is only beginning.