Magnetism is one of the most pervasive features of the Universe, with planets, stars and entire galaxies all having associated magnetic fields. All of these fields are generated by the motion of electrically conducting fluids, the so-called dynamo effect. The precise details of what drives the motion, and indeed what the fluid consists of, differ widely though. In this work the authors draw upon their expertise in geophysical and astrophysical MHD to explore some of these phenomena, and describe the similarities and differences between different magnetized objects. They also explain why magnetic fields are crucial in the formation of the stars, and discuss promising experiments currently being designed to study some of the relevant physics in the laboratory. This interdisciplinary approach makes the book appealing to a wide audience in physics, astrophysics and geophysics.

A main selection of Scientific American Book Club Magnetic fields permeate our vast universe, urging electrically charged particles on their courses, powering solar and stellar flares, and focusing the intense activity of pulsars and neutron stars. Magnetic fields are found in every corner of the cosmos. For decades, astrophysicists have identified them by their effects on visible light, radio waves, and x-rays. J. B. Zirker summarizes our deep knowledge of magnetism, pointing to what is yet unknown about its astrophysical applications. In clear, nonmathematical prose, Zirker follows the trail of magnetic exploration from the auroral belts of Earth to the farthest reaches of space. He guides readers on a fascinating journey of discovery to understand how magnetic forces are created and how they shape the universe. He provides the historical background needed to appreciate exciting new research by introducing readers to the great scientists who have studied magnetic fields. Students and amateur astronomers alike will appreciate the readable prose and comprehensive coverage of The Magnetic Universe.

This self-contained introduction to astrophysical magnetic fields provides a comprehensive review of the current state of the field and a critical discussion of the latest research. Its emphasis on results that are likely to form the basis for future progress benefits a broad audience of advanced students and active researchers.

Publisher description

The mystery of Earth's invisible, life-supporting power Alanna Mitchell's globe-trotting history of the science of electromagnetism and the Earth's magnetic field--right up to the latest indications that the North and South Poles may soon reverse, with apocalyptic results--will soon change the way you think about our planet. Award-winning journalist Alanna Mitchell's science storytelling introduce intriguing characters--from the thirteenth-century French investigations into magnetism and the Victorian-era discover that electricity and magnetism emerge from the same fundamental force to the latest research. No one has ever told so eloquently how the Earth itself came to be seen as a magnet, spinning in space with two poles, and that those poles have dramatically reversed many time, often coinciding with mass extinctions. The most recent reversal was 780,000 years ago. Mitchell explores indications that the Earth's magnetic force field is decaying faster than previously thought. When the poles switch, a process that takes many years, the Earth is unprotected from solar radiation storms that would, among other disturbances, wipe out much and possible all of our electromagnetic technology. Navigation for all kinds of animals is disrupted without a stable, magnetic North Pole. But can you imagine no satellites, no Internet, no smartphones--maybe no power grids at all? Alanna Mitchell offers a beautifully crafted narrative history of surprising ideas and science, illuminating invisible parts of our own planet that are constantly changing around us.