Solar storm intensifies, filling skies with northern lights
dramatic blast from the sun set off the highestlevel geomagnetic storm in
Earth’s atmosphere Friday, which was expected to make the northern lights visible as far south as Florida and Southern California and could interfere with power grids, commuA nications and navigation systems.
It was the strongest such storm to reach Earth since Halloween 2003. That storm was strong enough to create power outages in
Sweden and damage transformers in South Africa.
The effects could continue through the weekend as a steady stream of emissions from the sun continues to bombard the planet’s magnetic field.
The solar activity is so powerful that the National Oceanic and Atmospheric Administration, which monitors space weather, issued an unusual storm watch for the first time in 19 years, which was then upgraded to a warning.
The agency began observing outbursts on the sun’s surface Wednesday, with at least five heading in the direction of Earth.
“What we’re expecting over the next couple of days should be more significant than what we’ve seen certainly so far,” Mike Bettwy, the operations chief at NOAA’s Space Weather Prediction Center, said at a news conference Friday morning.
For people in many places, the most visible part of the storm will be the northern lights, known also as auroras. But authorities and companies will also be on the lookout for the event’s effects on infrastructure, like global positioning systems, radio communications and even electrical power.
While the northern lights are most often seen in higher latitudes closer to the North Pole, people in many more parts of the world are already getting a show this weekend that could last through the early part of next week.
As Friday turned to Saturday in Europe, people across the continent described skies hued in a mottling of colors.
Alfredo Carpineti, an astrophysicist, journalist and author in north London, saw them with his husband from the rooftop of their apartment building.
“It is incredible to able to see the aurora directly from one’s own backyard,” he said. “I was hoping to maybe catch a glimpse of green on the horizon, but it was all across the sky in both green and purple.”
The storm is caused by giant explosions on the surface of the sun, known as coronal mass ejections, that send streams of energetic particles into space.
Such outbursts may not cross our planet as it travels around the star. But when these particles create a disturbance in Earth’s magnetic field, it is known as a geomagnetic storm.
NOAA classifies these storms on a “G” scale of 1 to 5, with G1 being minor and G5 being extreme. The most extreme storms can cause widespread blackouts and damage to infrastructure on Earth. Satellites may also have trouble orienting themselves or sending or receiving information during these events.
The current storm is classified as G5, or “extreme.” It is caused by a cluster of sunspots – dark, cool regions on the solar surface – that is about 16 times the diameter of Earth. The cluster is flaring and ejecting material every six to 12 hours.