Development of Activity in McMath 128 and the 24 January 1971 Flare

The development of McMath 11128 is a fascinating example of the role of magnetic field reconnection and solar activity. When this active region came over the limb on January 14, it was an ordinary active region. The sunspots in the leading part, consisting of two p spots (p1 and p2) and one f spot (f1) remained almost identical for the entire period. However on January 19 a new sunspot group developed in the following part of the region and rapidly spread to overtake the f spot of the first group. In the subsequent reconnection of fields, a considerable amount of activity took place, finally leading up to the great flare of the 24th.