Scientific American's Ask the Experts

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 este...