Introduction

This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book examines plasma astrophysics includes space plasma physics, solar physics, and plasma astrophysics in a narrower sense. Plasma astrophysics is among the youngest disciplines in astrophysics. It attempts to understand the evolution of the Universe from the plasma astrophysics point of view. The central problem in plasma astrophysics is clarifying the origin and physics of such newly-discovered activity in various celestial objects. The aim of the plasma astrophysics is to clarify the physics of plasmas in various celestial objects, including the physics of celestial objects themselves. The book overviews the actual observations of typical celestial objects, by taking examples of astrophysical objects: galactic disks, active galactic nuclei, and cluster of galaxies.