This extreme ultraviolet wavelength image provided by NASA shows a solar flare. An impressive solar flare is heading toward Earth and could disrupt power grids, GPS and airplane flights. An impressive solar flare is heading toward Earth and could disrupt power grids, GPS and airplane flights. Forecasters at the National Oceanic and Atmospheric Administration's (NOAA) Space Weather Prediction Center said the sun erupted Tuesday evening and the effects should start smacking Earth late Wednesday night, close to midnight EST. They say it is the biggest in five years and growing. (AP Photo/NASA)
While some experts think the threat from the solar storm passed by Thursday afternoon, space weather forecasters said it's still too early to relax. That's because there's a chance the storm's effects could continue and even intensify through this morning.
On Tuesday, the sun produced two enormous X-class flares - the most powerful types of blasts to erupt from the sun's surface - that flung waves of charged particles into space. The particle bursts are called coronal mass ejections, or CMEs, and as they hit Earth's atmosphere they can disrupt communication satellites and power grids. But the interaction of CMEs with Earth's magnetic field also produces the incredible displays known as the northern lights, or aurora borealis.
Dr. Robert Collier, director of the Jack C. Davis Observatory at Western Nevada College, said Carson City residents may still be able to catch a glimpse of the aurora.
"It would be very dim, but it's possible," he said. "It could be a greenish hue and sometimes a really dark reddish-purple."
He suggested avoiding any light pollution.
"From Carson City, you won't have much luck looking straight north toward Reno because the light is too bright," he said. "The best way to do it is to look more to the northwest or northeast."
He said there is no ideal time to see it, but it's probably best to wait well into the night.
"You want to wait until it's nice and dark," he said. "The darker the better."
And you can't be in a hurry.
"It's not a continual thing," he said. "It will come and go in bursts. Just be patient."
Even still, he said, it could be that it's not visible here. For those still interested, he suggested checking out the web with sites like spaceweather.com.
And while this solar storm may have fizzled a bit, others may be lining up in the cosmic shooting gallery in the coming days month and year, scientists agree.
"It looks to me like it's over," NASA solar physicist David Hathaway said late Thursday afternoon, after noticing a drop in a key magnetic reading.
That conclusion is premature, said Doug Biesecker, a space scientist at the National Oceanic and Atmospheric Administration's Space Weather Prediction Center in Boulder, Colo., which forecasts solar storms. He pointed to an increase in a different magnetic field measurement.
The storm, which started with a solar flare Tuesday evening, caused a stir Wednesday because forecasts were for a strong storm with the potential to knock electrical grids offline, mess with GPS and harm satellites. It even forced airlines to reroute a few flights on Thursday.
North American utilities didn't report any problems, said Kimberly Mielcarek, spokeswoman for the North American Electric Reliability Corporation, a consortium of electricity grid operators.
It was never seen as a threat to people, just technology, and teased skywatchers with the prospect of colorful Northern Lights dipping further south.
But when the storm finally arrived around 6 a.m. EST Thursday, after traveling at 2.7 million mph, it was more a magnetic breeze than a gale. The power stayed on. So did GPS and satellites. And the promise of auroras seemed to be more of a mirage.
"I think we just lucked out," Jeffrey Hughes, director of the Center for Integrated Space Weather Modeling at Boston University, said Thursday afternoon. "It just didn't pack as strong a magnetic field as we were anticipating."
Scientists initially figured the storm would be the worst since 2006, but now seems only as bad as ones a few months ago, said Joe Kunches, a scientist at the NOAA center. The strongest storm in recorded history was probably in 1859, he said.
"It's not a terribly strong event. It's a very interesting event," Kunches said.
Forecasters can predict the speed a solar storm travels and its strength, but the north-south orientation is the wild card. This time it was a northern orientation, which is "pretty benign," Kunches said. Southern would have caused the most damaging technological disruption and biggest auroras.
• The Associated Press contributed to this report.
