sunspots

Try reading the wikipedia article on the Wilson Effect.

By what I can recall, sunspots are the visible manifestations of magnetic flux distortions or magnetic flux hurricanes that sink into the sun's convection zone that it represses / cancels a fraction of the whatever's going on the convection zone and hence the reduced temperature.

- p6
" True inspiration always comes to fulfill reason and is always in harmony with it " - Swami Vivekananda

Jupiter being the most influencial(in terms of greatest mass , volume & gravitational field & great magnetic field) planet in solar system . Its magnetosphere extends more than 650 million km in the direction toward the Sun. Since planets along with sun revolve around their common Centre of Mass ( This CM lies inside sun b'coz of sun's total mass > sum of all 10 planets) Jupiter's magnetic field overlaps with with the magnetic field of Sun. At any instant whichever the side Jupiter takes its position w.r.t sun it's magnetic field attracts with that of sun's & huge magnetic flux generates trapping a sheet of ionized particles from sun's surface resulting in the solar wind. At the same time on opposite side of sun diversion of magnetic field occurs & loss of temperature ocurrs fron a small patch of sun's area. Due to this loss of temp on other side of sun area becomes darker which is viewed as solar spot. since Jupiter has a revolution period of 11.78 yrs(approx.) so sun's dark spots also comes after each 11.6 yrs (=~). In the mid of this period ie: after 6 yrs sun spots are minimum ...since Jupiter's presence at the other side where solar wind would be getting generated.

This is what i recalled after watching TV programme on sun's spot.