These are interesting times for our understanding of the origins, evolution and effects of the Sun’s magnetic field. Satellite missions such as Yohkoh, SOHO, Ulysses and TRACE have returned outstanding new data, and helioseismology has allowed us to see into the solar interior for the first time. The discovery of a shear layer between the surface of the Sun – the “photosphere” – and its centre has great implications for our understanding of the dynamo that is responsible for generating the solar magnetic field. Meanwhile, much research has been aimed at understanding the 11-year cycle in the field and the wide variety of phenomena that it modulates.
In the March issue of Physics World, Mike Lockwood of Rutherford Appleton Laboratory and Southampton University, UK, and Duncan H Mackay of the University of St Andrews, UK, underline the significance of the solar magnetic field in our understanding of the solar flux and cosmic rays in particular.
