Solar Flare Disrupts Communication, Navigation

One of the largest solar flares ever recorded was observed Wednesday afternoon by forecasters at the NOAA Space Environment Center, and scientists are predicting more significant flares could occur over the next two weeks.

Spacecraft operations, electric power, high-frequency communications, and low-frequency navigation systems could all experience disruptions. The flare came from the same region, called Sunspot 798, that caused the northern lights to be visible as far south as Colorado in the northern hemisphere, and the southern lights as far north as Australia and New Zealand in July.

"This event created a complete blackout of high frequency communications on the day lit side of Earth, which included the entire U.S. and basically anywhere the sun was shining at this time," said Larry Combs, a forecaster at the Space Environment Center.

Combs said that emergency service communication along the Gulf Coast supporting the Katrina relief effort might have experienced some degradation for up to several hours following the solar flare.

The flare was measured at X-17, which rates as a severe disruption to radio communications. According to the NOAA Space Weather Scale, severe disruptions cause high-frequency radio blackouts, as well as disruptions to low frequency and satellite navigation for up to two hours.

Scientists say that the flare was not directed at Earth, minimizing its impact. However, over the next two weeks the region will rotate towards Earth and there is a good chance another "X class" flare could occur.

While the most common side effect on Earth from solar flares is the aurora borealis, flares have been known to cause widespread disruption of power lines. On March 6, 1989, a relatively small flare caused a blackout in parts of Canada.