The Spin on the ``Source Surface'' of the Solar Wind

This observational study of coronal rotation is based on the K-coronameters aboard SOHO, the SOlar and Heliospheric Observatory. Sunspots occur within 35 degrees of the equator. Extensions of active regions into the atmosphere persist for sufficiently long that their sightings at the Sun's edge serve as timing markers to measure rotation. But magnetic structures other than those originating in active regions also reach the base of the solar wind, and the strongest rotation signal in 2002 is from latitudes higher than sunspots and is a feature of the neutral sheet of a tipped magnetic dipole. Come see the pictures.