Speaker
Description
The magnetic activity of stars like the Sun is driven by the interplay of rotation and convection that fuels dynamo-action in their interiors. At the surface, dynamo-generated magnetic fields emerge as "spots" or active regions that influence the circumstellar environment via winds, radiation, and transient events like flares and coronal mass ejections (collectively “space weather”). Flux emergence often creates nested active regions whose persistence is central to the evolution of the Sun’s large-scale magnetic field. These regions can anchor the heliospheric current sheet and stall the reversal of the coronal magnetic field for several solar rotations. During the 11-year solar cycle, the distribution of solar wind sources undergoes a significant shift in response to the evolution of the large-scale magnetic field, transitioning from polar coronal holes at solar minima towards the active latitudes and equatorial coronal holes during maxima. This topological evolution modulates the mean rotation rate of the solar wind; rotation is slower during minima when sources are polar and faster (Carrington-like) during maxima when open field lines are anchored at lower latitudes. With ESA’s Solar Orbiter and NASA’s Parker Solar Probe exploring the inner heliosphere, the heliophysics community is building a global view of solar magnetism at both large and small scales. This talk highlights how the internal generation of magnetic field and its subsequent emergence to the surface collectively shape the heliosphere and the near-Earth space climate.