The Stars

The year 1996 will see the seventieth anniversary of the publication of The Internal Constitution 01 the Stars by Sir Arthur Eddington. This book re mains a masterpiece, a classic in the astrophysical literature. In essence it proved that it was possible to construct a theory that made it possi ble to look inside the stars. However, theoretical astrophysics remained the province of a very small number of people for many years. Quite a few re markable textbooks have been published since, but there always remained the need to have a book, however incomplete, that took into account the fact that the study of the stars raises global problems. Whichever part of a star is studied, that part is of course connected to the rest of the star. Furthermore, all fields of physics are involved. The incredible increase in precision of astrophysical data and the wide variety of new types of ob servation (from neutrinos to asteroseismology) obliged researchers to take into account new physical processes and to improve their knowledge of basic physical processes (the equation of state, opacities, nuclear cross-sections, plasma physics and magnetohydrodynamics, to name just the most impor tant). Remember that astrophysics is first and foremost a science of observa tion. But theoretical developments are essential if we are to understand the observed phenomena.