The importance of magnetic fields in astrophysical processes has long been recognized. A thriving field of research is centered on the life cycle (the creation, evolution, and destruction) of magnetic fields in astrophysical plasmas, and prominently in solar physics. The discovery by Hale in 1908... Show moreThe importance of magnetic fields in astrophysical processes has long been recognized. A thriving field of research is centered on the life cycle (the creation, evolution, and destruction) of magnetic fields in astrophysical plasmas, and prominently in solar physics. The discovery by Hale in 1908 that sunspots are associated with strong magnetic fields (1) spurred advances in spectroscopy, polarimetry, instrument development, and research into solar magnetism. Magnetism is now known to be the key to most unsolved problems in solar physics, including the 11-year activity cycle, chromospheric and coronal heating, flares, coronal mass ejections, and space weather. Even though more than a century has passed since the discovery of magnetism in the solar atmosphere, these measurements remain difficult. Show less
