An Historical Sunspot at Sun. The Sun kindly provided us lately with a fine picture. Since July, 17th a large sunspot appeared on eastern limb and transited the Sun's disk until July, 29th. Sun is an active radiative and magnetic body. Sunspots are places of intense magnetic loops activity of which is believed to prevent the heat coming from below to reach the solar surface. Hence the plasma become cooler. Hence darker as seen on the background of the usual solar surface. Sun's surface has a temperature of 10,400° F as sunspots are about 7,100° F. Usual sunspots are of the size of one of the dark components of the large sunspot. Hence this large sunspot is an historical one, encompassing about 125,000 miles (200,000 km). This sunspot is remarkable too because Sun should be less active now. Sun is working on a 11-year cycle, reaching a maximum of activity then a minimum. At its maximum the Sun is displaying numerous sunspots and some may reach remarkable sizes. About 6 years later sunspots are rare and mostly small-sized. As the Sun is presently is a descending phase of a cycle, bound to reach its minimum about 2006, activity should decrease as should sunspots size. picture courtesy SOHO daily pictures
