Magnetic Activity in Stars, Discs and Quasars

Donald Lynden-Bell

Published 2000-07-14Version 1

Although magnetic fields in interstellar matter were postulated almost fifty years ago, magnetohydrodynamic theory was then much hampered by our inability to see what the magnetic field configurations were like and, after a decade of innovative development, cynics, not without some justification, began to claim that anything can happen when magnetism and an imaginative theorist get together. Thus cosmic lightning in particular received a bad press. More recently great advances in observational techniques that we shall hear of from Title, Beck, Moran and Mirabel have enabled us to see not only the sun's magnetic field with unprecedented clarity but the fields in galaxies, quasars and microquasars are now measured and not merely figments of fertile imaginations.