Sunspots tend to occur in groups and are combined with other phenomena of solar activity such as faculae, filaments and flares. Although sunspots have an average temperature of 3700K they appear dark compared to the brighter surrounding regions which have an approx. The development of the different phenomena proceed at varing rates. Larger sunspot groups tend to consist of two larger magnetically linked spots surrounded by smaller spots. This is a typical 'bipolar' group.
Sunspots have a lifetime from as little as a few hours to many weeks.
Sunspot activity has a life cycle of approximately 11 years. At the end of the 11 year cycle the magnetic polarity of the spots changes and a further cycle starts. This represents a 22 year magnetic cycle. How sunspots form The occurance of sunspots is related to other solar phenomena such as faculae, flares and protuberances which in turn are all influenced by the solar magnetic field. If the magnetic flux in the stressed regions exceed a value of 0.1 tesla faculae may appear.