Introduction to the Sun

Abstract

The Sun has a basic impact on human life; thus, during our existence man has viewed our star in many different ways. From the scientific point of view, the only one of concern here, the Sun is an analog of the Rosetta stone for stellar studies, thanks to its closeness to the Earth. This book is limited to the introduction of the structure and evolution of our star and neglects the solar magnetic field and related phenomena. As a consequence, we treat the Sun as a spherically symmetric star, with an atmosphere made only of the photosphere, which is constant for most of its lifetime. Even with this restriction we can address many fundamental questions which concern the global physical parameters of the Sun, the present model of its internal structure, its energy source and the way the energy flows outwards and, finally, the evolution of our star from its formation to its shutdown. This introductory chapter contains two sections, the first summarizes our approach and the second describes the basic solar data.