About the book: 1963 / Have you ever thought about how many colors are in the rainbow? Seven, or maybe nine, as the title of the book says? It turns out that there are much more of them, but at the same time, the title of the book is correct. Why is this so? From this book you will learn what visible and invisible light is, how it helps people understand and explore the world around them, penetrate deep into matter and into space. In addition, you will read about how man learned to see in the dark, transmit images over vast distances and capture processes that last millionths of a second. All this and other new achievements of science and technology are described in the book “Nine Colors of the Rainbow».