Dropped and Lost Cell Calls? Sun Might Be to Blame

Jan. 11, 2008 — -- Chances are you probably missed last week's appearance of Sunspot No. 10,981 on the surface of the sun.

But scientists say its arrival signals the beginning of a cycle of solar storms that could make everything from your cell phone to the GPS navigation system in your car temporarily stop working. And in severe storms, experts say it's possible entire power grids could be knocked out, leaving millions in the dark.

Sunspots are areas of intense magnetic activity on the sun that appear on roughly an 11-year cycle. The location and characteristics of Sunspot No. 10,981 tell scientists that the newest cycle -- known as Solar Cycle 24 -- has begun. The solar activity can release tremendous blasts of energy toward Earth -- interfering with an array of sensitive electronic systems.

Experts say the periods of solar storm activity should gradually increase, peaking by the year 2011 or 2012.

Dale Gary, a solar physicist who chairs the physics department at the New Jersey Institute of Technology, says cell phone towers will likely bear the brunt of a solar storm.

"It can affect quite a number of towers in a given region," said Gary, who notes one study he conducted showed a typical storm could affect about 7 percent of all cell phone calls. A stronger storm could make the problem worse.

Of particular concern, experts say, is the effect solar storms could have on GPS navigation devices that have come into much wider civilian use in the last five years.

The system relies on Earth-orbiting satellites to provide precise locations anywhere on the planet. But solar storms could make GPS receivers unable to lock onto a satellite signal, rendering them useless. The effect could last for minutes or more than a day. You may be reduced to -- gasp -- stopping to ask for directions.

"The civilian use of GPS has really taken off only in the last few years, so we really do expect to see a much wider impact in this upcoming cycle," said Douglas Biesecker, a solar physicist at the Space Weather Prediction Center in Colorado, run by the National Oceanic and Atmospheric Administration.