Earth Will Feel Solar Flares Caused by Giant Sunspots

OFFUTT AIR FORCE BASE, Nebraska, October 24, 2003 (ENS) - Space weather technicians with the U.S. Air Force Weather Agency and the National Aeronautics and Space Administration (NASA) are currently tracking large groups of sunspots moving across the Sun. They are forecasting moderate to extreme solar flares for the next few days that will affect electronic equipment on Earth and in orbit around the planet.

Because the solar flares could cause geomagnetic storms, Air Force technicians have warned U.S. Defense Department officials and the national intelligence community to expect significant solar activity, says Jodie Grigsby of the Air Force Weather Agency.

Two enormous sunspots, each the size of the planet Jupiter, are now moving across the face of the Sun. Named "484" and "486," they have complex magnetic fields that harbor energy for large X-class solar flares, according to NASA.

Chris Blomquist of Ft, Lauderdale, Florida took this photo showing one of the two large sunpots on October 23, 2003. (Photo courtesy NASA)

A solar flare is an explosion on the Sun that happens when energy stored in twisted magnetic fields, usually above sunspots, is suddenly released. Flares produce a burst of radiation across the electromagnetic spectrum, from radio waves to x-rays and gamma-rays,

On Earth, electromagnetic signals can be directly impacted by the interference of atmospheric disturbances caused by these solar flares. Based on their recordings of these disturbances, the space weather technicians create text and graphics products for use in defense mission planning and environmental awareness programs.

These disturbances influence high frequency communications, satellite ultra-high frequency communications, Global Positioning System navigation signals, and certain radars, Grigsby says.

Satellites and other equipment in orbit above the protective levels of the atmosphere may suffer degradation of components because of this solar radiation, said Air Force weather officials.

There can be increased drag on satellites in low orbits above the Earth, and officials who track satellites and other orbiting objects can lose their targets because of these changes in the atmosphere.

The geomagnetic storms may cause the aurora borealis, commonly known as the Northern Lights, to be pushed toward the equator, allowing people in the continental United States to have a better view.

NASA reports that a coronal mass ejection from the Sun swept past Earth at approximately 1500 UT (8:00 am PDT) today and triggered a strong geomagnetic storm. The ejection struck during daylight hours in Europe and North America, so few people saw any Northern Lights, NASA said.