E-raamat: Stars in their evolution

What is the origin of the universe? How did the stars form? How old is a star like our sun? How old are the atoms of the elements that make up the universe? What will happen to these stars that adorn the sky after billions of years? At first glance, these questions may seem like intractable mysteries that cannot be answered or even contemplated! The situation of someone asked to answer these questions is not much different from that of someone asked to tell us about the evolution of living things, their origins, and what awaits them in the near and distant future. All he had at hand was a photograph taken suddenly of several living things somewhere! For the astronomer has nothing but a picture of the sky and its various objects, and although he has observed this picture for thousands of years and began studying it with some precision decades ago, it appears to be static and without any noticeable change. The subject of the evolution, origin, and end of the universe is a difficult and complex subject, and the information upon which astronomers base their opinions is not mature enough to provide the final say. This book is one such attempt, and I believe it is a successful one. It was written by one of the pillars of astronomy in the modern era, Mrs. Ceciliapin-Gaposchkin.