“Actually,” Dr. Durney continued, “the sun has many unusual movements. Since everything on the sun is gaseous, parts of the sun’s surface can rotate faster than others. . . . By constantly viewing the sun as we do here at the Sunspot observatory, we can determine how the inside of the sun is rotating. . . . Since the sun rotates faster at its equator, much mixing occurs on the surface, and this causes many strange phenomena. This unusual movement creates magnetic fields deep inside the sun, which float to the surface. Sunspots on the sun are a manifestation of these magnetic fields.”

Sunspots are one of the more interesting features of the sun and one that affects us on earth. Sunspots were first observed by Galileo. Later it was determined that a sunspot cycle lasts 11 years and that a complete sunspot cycle has two 11-​year periods of sunspot activity. As Dr. Durney explained: “Sunspots are magnetic fields. They are dark because they block the motions that transport energy. Flares are thought to be caused by the annihilation of these magnetic fields on the sun’s surface, which then release enormous amounts of energy that affect us by disrupting radio waves and by electrifying parts of our atmosphere. This energy also causes what are called northern lights and southern lights, or auroras, a wonder to mankind throughout history.”

Sun studies may help to predict the geomagnetic storms that may occur in our atmosphere when there is sunspot activity. These affect world communications and thus the activities dependent on good radio communication, such as air travel. Because of the high cost of satellite transmission, most communication is still done by means of radio transmitters on the ground. The energy released by sunspots disrupts the shell of ionized particles surrounding the earth that reflects the radio waves back to earth. When the shell is ineffective, radio messages are lost.

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Sunspots

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National Optical Astronomy Observatories