John Dyson made outstanding research contributions over many years to our

understanding of the responses of interstellar media to winds from stars and

from active galaxies. He had a huge influence on these subjects and his work

gained an international reputation. Much of his career was at the University of

Manchester where he became Professor of Astronomy and Head of Astrophysics.

He moved in 1996 to the University of Leeds, becoming Dean of Research, and

was appointed Emeritus Research Professor in 2006.

He died in 2010 and is much missed by friends and colleagues world-wide

who valued his scientific insight, quick wit, kindness and generosity.

David Williams is currently Emeritus Perren Professor of Astronomy at University

College London. While at NASA's Goddard Space Flight Center in the 1960s he

became interested in interstellar molecules and interstellar dust as potential

probes of the interstellar medium. When John Dyson and David were both

working in Manchester, John emphasised the importance of cosmic gas dynamics

in understanding interstellar chemistry and dust, and David built a research

group at UMIST to investigate these and other topics. He left Manchester in

1994 for UCL and has continued to study problems in interstellar physics and

chemistry.

Contents

Preface to the Third Edition ............................................................................vii

Some Relevant Physical and Astronomical Information...................................ix

Authors.............................................................................................................xi

Chapter 1 Introduction..................................................................................... 1

Chapter 2 How We Obtain Information about the Interstellar Medium........... 9

Chapter 3 Microscopic Processes in the Interstellar Medium ......................... 31

Chapter 4 Interstellar Grains.......................................................................... 51

Chapter 5 Radiatively Excited Regions........................................................... 79

Chapter 6 Introduction to Gas Dynamics .................................................... 103

Chapter 7 Gas Dynamical Effects of Stars on the Interstellar Medium........ 135

Chapter 8 Star Formation and Star-Forming Regions.................................. 169

Answers to Problems ...................................................................................... 187

Index.............................................................................................................. 191