Tuesday 24 January 2012

Biggest solar storm since 2005 underway, will peak Tuesday

Image: NASA's Solar Dynamics Observatory captured the M9-class solar flare's extreme ultraviolet flash - NASA

Fast on the heels of a solar storm that delivered a glancing blow over the weekend — triggering bright auroras in Canada and Scandinavia — the sun released an even more energetic blast of radiation and charged plasma overnight that could disrupt GPS signals and the electrical grid Tuesday, especially at high latitudes, space weather experts warned Monday morning.

Already, the storm could be disrupting satellite communications as streams of radiation from the sun bounce across the Earth’s magnetic field, which extends above the surface into space.

“With the radiation storm in progress now, satellite operators could be experiencing trouble, and there are probably impacts as well to high frequency [radio] communications in polar regions,” said Doug Biesecker, a physicist at the Space Weather Prediction Center, part of the National Oceanic and Atmospheric Administration in Boulder, Colo.

Such radio blackouts can force airlines to reroute flights between North America and Europe or Asia.

Biesecker said any rocket launches scheduled for Monday probably would have to be scrubbed, although he said he was unaware of any planned launches.

The solar storm is the biggest since 2005, he added.

The storm will peak Tuesday when a speeding cloud of plasma and charged particles blasts past Earth, distorting the planet’s magnetic field with impacts possibly ranging as far south in latitude as Texas and Arizona.

“We expect moderate to potentially strong geomagnetic storming that can cause pipeline corrosion effects and power grid fluctuations,” Biesecker said.

Predictions from NASA scientists show the storm peaking about 9 a.m. Tuesday, although uncertainty in the prediction means the storm could peak up to seven hours earlier or later, said Michael Hesse of NASA’s Space Weather Laboratory, at the Goddard Space Flight Center in Greenbelt.

“It’s not going to be a catastrophe, but there could be noticeable geomagnetic current induced on the electrical grid,” Hesse said.

The storm began with a burst of X-rays shooting out of a sunspot — the same trouble spot that generated the previous storm — about 11 p.m. Sunday. A huge explosion of plasma, which scientists call a coronal mass ejection, then followed. The giant plasma cloud pushed an advancing wave of energized protons at the Earth, and that wavefront is now triggering the radiation storm in progress in the atmosphere.

The bulk of the plasma cloud — a mess of super-energized electrons and protons — is speeding toward Earth at some 4.5 million mph, according to Hesse’s calculations, which are based on observations from NASA’s four sun-watching satellites.

“What’s special about this event is the coronal mass ejection that erupted is by far the fastest Earth-directed event of this solar cycle,” Biesecker said.

And speed matters. The faster a cloud of plasma travels, the bigger its impacts on Earth.

Hesse said that NASA systems sent an automated solar storm alert to satellite operators and the Electric Power Research Institute. Hesse also notified the White House’s Office of Science and Technology Policy on Monday morning.

Disruptions to GPS signals and the power grid could extend far south, Hesse said. But he said that estimating the spread of the impact was difficult.

A strong aurora over much of North America is possible Tuesday night, Hesse added.

“We’re going to be monitoring this,” he said. “The models we use to predict these events are not correct all the time. But at the moment, it looks like it will be pretty interesting.”

Solar activity waxes and wanes on a roughly 11-year cycle. The current cycle is ramping up toward an expected peak in 2013 or 2014.

- Washington Post

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