Starspot

A sunspot is a region on the Sun's surface (photosphere) that is marked by a lower temperature than its surroundings and has intense magnetic activity, which inhibits convection, forming areas of low surface temperature. Although they are blindingly bright at temperatures of roughly 4000-4500 K, the contrast with the surrounding material at about 5800 K leaves them clearly visible as dark spots. If they were isolated from the surrounding photosphere they would be brighter than an  electric arc. A minimum in the eleven-year sunspot cycle is predicted for 2007 [1]. Sunspots are often related to intense magnetic activity such as coronal loops and reconnection. Most solar flares and coronal mass ejections originate in magnetically active regions around sunspot groupings. Similar phenomena observed on stars other than the Sun are commonly called starspots.
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