Why is the night sky dark? Why do hangovers occur? Will time travel ever be a reality? Find the answers to the most puzzling and thought-provoking questions about the world of science from the experts at Scientific American.

Why is the night sky dark? How do dolphins sleep without drowning? Why do hangovers occur? Will time travel ever be a reality? What makes a knuckleball appear to flutter? Why are craters always round?

There's only one source to turn to for the answers to the most puzzling and thought-provoking questions about the world of science: Scientific American. Writing in a fun and accessible style, an esteemed team of scientists and educators will lead you on a wild ride from the far reaches of the universe to the natural world right in your own backyard. Along the way, you'll discover solutions to some of life's quirkiest conundrums, such as why cats purr, how frogs survive winter without freezing, why snowflakes are symmetrical, and much more. Even if you haven't picked up a science book since your school days, these tantalizing Q & A's will shed new light on the world around you, inside you, below you, above you, and beyond!