The Wilson effect is explained by assuming that these are hollow. Spörer's law describes the change in the latitude of their 
The Wilson effect is explained by assuming that these are hollow. Spörer's law describes the change in the latitude of their formation. They have two regions, an umbra and a penumbra, and are associated with faculae, luminous hydrogen clouds which seem to precede them. _FOR 10 POINTS_—name these objects, which appear to follow an eleven-year cycle on the solar surface.
The Wilson effect is explained by assuming that these are hollow.
{Sunspot}s