A NASA satellite image shows a pair of active regions on the surface of 
the...


A powerful solar eruption that triggered a huge geomagnetic storm has 
disturbed radio communications and could disrupt electrical power grids, 
radio and satellite communication in the next days, NASA said.
A strong wave of charged plasma particles emanating from the Jupiter-sized 
sun spot, the most powerful seen in four years, has already disrupted radio 
communication in southern China.

The Class X flash -- the largest such category -- erupted at 0156 GMT 
Tuesday, according to the US space agency.

"X-class flares are the most powerful of all solar events that can trigger 
radio blackouts and long-lasting radiation storms," disturbing 
telecommunications and electric grids, NASA said Wednesday.

Geomagnetic storms usually last 24 to 48 hours -- but some could last for 
many days, read a statement from the US National Weather Service.

"Ground to air, ship to shore, short-wave broadcast and amateur radio are 
vulnerable to disruption during geomagnetic storms. Navigation systems like 
GPS can also be adversely affected."

NASA's Solar Dynamics Observatory said it saw a large coronal mass ejection 
(CME) associated with the flash blasting toward Earth at about 560 miles per 
second (900 kilometers per second).

The flare spread from Active Region 1158 in the sun's southern hemisphere, 
which had so far lagged behind the northern hemisphere in flash activity. It 
followed several smaller flares in recent days.

"The calm before the storm," read a statement on the US National Weather 
Service Space Weather Prediction Service.

"Three CMEs are enroute, all a part of the Radio Blackout events on February 
13, 14, and 15 (UTC). The last of the three seems to be the fastest and may 
catch both of the forerunners about mid to late ... February 17."

The China Meteorological Administration reported that the solar flare caused 
"sudden ionospheric disturbances" in the atmosphere above China and jammed 
short-wave radio communications in the southern part of the country.

The CMA warned there was a high probability that large solar flares would 
appear over the next three days, the official Xinhua news agency reported.

The British Geological Survey (BGS) said meanwhile that the solar storm 
would result in spectacular Northern Lights displays starting Thursday.

One coronal mass ejection reached Earth on February 14, "sparking 
Valentine's Day displays of the Northern Lights (aurora borealis) further 
south than usual."

"Two CMEs are expected to arrive in the next 24-48 hours and further... 
displays are possible some time over the next two nights if skies are 
clear," it said.