Image by the Ultraviolet Imager on NASA's Polar spacecraft showing UV emissions from aurora borealis during a strong geomagnetic storm, October 22, 1999. Courtesy NOAA Space Environment Center, Suitland, Maryland. As the sun becomes increasingly active and explosive in its eleven year cycle which is expected to reach maximum activity around June to July 2000, there will be more geomagnetic storms on earth and more aurora borealis, like the beautiful photograph taken by Dick Hutchinson in January 1998 above a frozen landscape of snow-covered spruce trees in Alaska. These events were caused by high-speed material streaming out from areas on the sun known as coronal holes. Space weather forecasters expect moderate levels of aurorae, shortwave radio disruptions, and power grid fluctuations at high latitudes to become more common as the solar cycle reaches maximum.
Prominences are loops of magnetic fields with hot gas trapped inside.
Sometimes, as the fields become unstable, the prominence will erupt as this one did and become part of a coronal mass ejection. As sunspot numbers mount, coronal mass ejections and solar wind disturbances will trigger more and more geomagnetic storms. In extreme cases, these storms can induce electric currents in the earth and oceans that interfere with electric power transmission equipiment. Graph courtesy of NASA's Marshall Space Flight Center, October 1999. This creates added drag in the area where low-earth orbit satellites and the Space Shuttle orbit.