ABSTRACT
At night, an astronaut on the International Space Station glances down quietly at planet Earth. What does she see? Sparkles of electricity illuminate our major cities and continents. Our planet did not always look like this, of course. The first light bulb began to shine in 1879. Before this, with nightfall, the Earth was plunged in relative darkness punctuated by the occasional lightning storm. Today, however, a satellite image of our planet at night captures the pulse of our modern industrial heartbeat. But what if our planet were lit up by information instead of light bulbs? What would that pulse look like? Not much different at all, surprisingly.
