Solar storms like the one that buffeted the Earth’s magnetic field Thursday will soon become a common occurrence.
Magnetic eruptions on the sun Tuesday and Wednesday released two huge bursts of light — two of the largest solar flares over the past five years — and accelerated a blob of high-speed particles headed toward us. As the charged particles slam the Earth’s magnetic field at more than 1 million mph and are funneled toward the north and south poles, they generate the nighttime light now known as auroras or northern and southern lights.
Giant solar storms can wreak havoc on satellites and power grids. One storm knocked out power in a large area in Quebec in 1989. The current storm, which started Thursday morning, is nowhere large enough to cause that much trouble.
“At this point it’s a minor storm,” said C. Alex Young, a senior solar physicist at NASA’s Goddard Space Flight Center in Greenbelt, Md. “It’s not going to be that big even if the levels increase a bit. This is really not something to be concerned about.”
The storm particles started shaking the Earth’s magnetic field Thursday morning; the disturbance was “minor,” or 1, on the 1-to-5 scale used to describe the intensity of such storms. The intensity was expected to rise during the day, although it appeared weaker than the initial prediction that the storm would reach the “strong” threshold. A similar size storm hit Earth in late January.
There has been a five-year lull in strong solar storms because the ferocity and pace of the sun’s flares and magnetic eruptions rise and fall on an 11-year cycle, and the sun has only recently emerged from its slumber and started generating new flares.
“We’re getting the first few snowfalls of the year, so to speak,” said Robert Rutledge, lead of the forecast office at the Space Weather Prediction Center in Boulder, Colo., part of the National Oceanic and Atmospheric Administration.
During the course of a typical 11-year cycle, some 200 solar storms as strong as Thursday’s will hit Earth. Even though the current cycle appears quieter than usual, solar storms as strong as Thursday’s will likely hit the Earth a few times a week when the cycle peaks in the next year or so.
If the cycle matches the usual pattern, about a tenth as many of the solar storms — 10 to 20 — would reach the stronger, “severe” level, and one or two would be described as “extreme.”