Spawning and Shedding Helical Magnetic Fields in the Solar Atmosphere

Measurements of the helical fields in interplanetary magnetic clouds have corroborated recent evidence that the magnetic fields in solar filaments in the northern and southern hemispheres of the Sun are preferentially left‐handed and right‐handed heliform, respectively. In 13 cases out of 16, the chirality of magnetic clouds passing Earth about 4 days after a filament eruption or an eruptive solar flare corresponded to the predominant chirality in the hemisphere originating the solar event. Active regions and sunspots also indicate that helicity is segregated by hemisphere. Torque due to an equatorial jet stream beneath the photosphere may twist the fields.