The Big Book of Why

Why are trees green and clouds grey? Where do crayfish spend the winter and why do starfish have rays? Is there life on Mars and is it possible to walk on Saturn? You will find answers to these and many other questions in our book. Nature is in no hurry to reveal its secrets to man, so scientists, trying to unravel them, put forward a lot of hypotheses. We have given the most common of them. We hope that your journey into the world of the unknown will be exciting. The book is addressed to inquisitive young readers, as well as their caring parents.