Why does the Sun have spots?

   Why does the Sun have spots?

 The sun is not only a turbulent mass of hydrogen and helium gas. Enormous electric currents generate

Vast magnetic fields, which come and go as dark spots on the Sun's surface. These spots form in gronups, grow in intensity and number, reaching a peak every cleven years. The cyclical nature of the Sunspots was first discovered in the nineteenth century, A German amateur astronomer, Heinrich Schwabe, hoping to see a planet pass in front of the Sun's shining dise, became interested instead in some dark spots in its surface. For about seventeen ycars, he sketched the position of these spots and, by 1843, had established their pattern. Early this century, American astronomer George Hale added to Schwabe's work. He discovered that sunspots produce intense magnetic activity and that those with strongest force are about 8000 times as powerful as the Earth's magnetic field at its surface. Subsequent work has shown that sunspots, many of which are several times the size of the Earth, are part of vast solar storms. From time to time, magnetic fields reach the Sun's surface from far below. They block the flow of heat and light from the core so effectively that, where they appear -marked by a dark patch- the surface is at least 1000'c cooler than adjacent areas. If these flare-ups occur near the centre of the Sun's disc and facing the Earth, they can produce a magnetic storm in our polar regions. As a result of this, radio reception becomes crackly, compasses go awry, and our weather may suddenly change.