Like most people, the first time I realised just how small we are, I was a kid. It’s a vivid memory, one that’s burnt into my brain. I must have been about ten years old, lying on my bed and staring up through the window at the night sky. Of course, living in Britain, the sky was mostly covered with clouds, but every so often the wind would sweep them aside, and I’d be treated to a clear, unobstructed view of the sky above. The stars were fascinating. Those little pinpricks o