Tyson describes the beginning of the universe, dark matter, the spaces between planetary orbits, solar systems and galaxies, the shapes of galaxies, and delivers by the barrowload fun facts. Because it's short and for people in a hurry, the reader who knows nothing of astrophysics raises questions: how do theoretical physicists develop models, without laboratories? (They use their imaginations.) How are elements found only within a gigantic hadron collider identified and named? how are temperatures of the sun, space and planets measured? What is the likelihood of an asteroid breaking free of its belt and falling to the earth? How large does that asteroid have to be to wipe out most living matter upon impact? These and more questions Astrophysics for People in a Hurry answers.