WASHINGTON (AFP) - A potent solar flare has unleashed the biggest radiation storm since 2005 and could disrupt some satellite communications in the polar regions, US space weather monitors said Monday.
The event started late Sunday with a moderate-sized solar flare that erupted right near the center of the Sun, said Doug Biesecker, a physicist with the National Oceanic and Atmospheric Administration Space Weather Prediction Center.
"The flare itself was nothing spectacular, but it sent off a very fast coronal mass ejection traveling four million miles per hour (6.4 million kilometers per hour)," he told AFP.
A rush of radiation in the form of solar protons already has begun bombarding the Earth and is likely to continue through Wednesday.
The radiation storm is the largest of its kind since 2005 but still ranks only a three on the scale of one to five, enough to be considered "strong" but not "severe," he added.
NOAA said its website the S3 ranking means "it could, e.g., cause isolated reboots of computers onboard Earth-orbiting satellites and interfere with polar radio communications."
Biesecker said that when it comes to radiation storms, the polar regions are affected most.
For instance, the storm could spell disruptions to airline flights, oil operations, Arctic exploration and space satellites.
Night-sky viewers in Asia and Europe may be able to witness the aurora, or Northern Lights, late Tuesday as a result of the storm.
"We don't expect major impacts from an event like this," Biesecker said.
"It's the people who need GPS (global positioning system) accuracy of centimeters who have to worry, not people who want to know if you're going to turn the car 30 meters (100 feet) ahead."

1) How are flights o the polar routes going to cope or deal with this
if the solar discharge takes only about 8 minutes to reach the earth's
atmosphere?

A study by Mertens of polar flights during a solar storm in 2003 showed that passengers received about 12 percent of the annual radiation limit recommended by the International Committee on Radiological Protection. The exposures were greater than on typical flights at lower latitudes, and confirmed concerns about commercial flights using polar routes.

While the flights studied appear to have not put passengers in danger of exceeding the safe radiation limit on an individual flight, concerns remain, Mertens said. Many workers whose jobs expose them to consistent radiation sources log that exposure to keep a record over one's career. This is not the case for commercial aircrew, which receive the highest radiation levels of any occupationally exposed group.

People who work on commercial airline flights are technically listed as "radiation workers" by the federal government – a classification that includes nuclear plant workers and X-ray technicians. But unlike some others in that category, flight crews do not quantify the radiation they are exposed to.

Light takes 8 minutes, travelling at the speed of. Protons, having mass, wander along at a lower speed

if recent findings are to be believed, there are electromagnetic radiation which can exceed the speed of light