Fourteen billion years ago, the universe was little more than a cloud of hot hydrogen gas. I will tell the story of how that cloud of gas evolved into all of the galaxies, stars, and planets we see around us today. In the process, I’ll explain some of how astronomers study the history of the universe, and how telescopes are secretly time machines that let us look directly into the distant past. I’ll also talk about some of the great mysteries that remain in this story, and how we’re working in Toronto and elsewhere to solve them.