Stephen Hawking, truly one of the most sentient human beings in the known universe, has surmised recently that time is short on Earth. "With climate change, overdue asteroid strikes, epidemics and population growth," he says, "our own planet is increasingly precarious." In 2010, Hawking famously warned that we had but two centuries to colonize space and save ourselves. Now, however, it would appear that we are down to a single century—and even less if we allow artificial intelligence to supersede us. Yet Hawking is not disheartened, no indeed. It is a “glorious time to be alive," says he.