A huge sunspot unleashed a blob of charged plasma Thursday that space-weather watchers predict will blast past the Earth today. Satellite operators and power companies are keeping a close eye on the incoming cloud, which could distort the Earth's magnetic field and disrupt radio communications, especially at higher latitudes.
"Our simulations show potential to pack a good punch to Earth's near-space environment," said Antti Pulkkinen of the Space Weather Laboratory at NASA's Goddard Space Flight Center in Greenbelt, Md. But, "we're not looking at an extreme event here."
The front edge of the burst should arrive this morning, said Joseph Kunches, a spokesman for the Space Weather Prediction Center, part of the National Oceanic and Atmospheric Administration in Boulder, Colo.
"At first glance, it was, 'Oh, my God, it's at the center of the [sun's] disk, it ought to go right to the Earth,' " Kunches said. But upon further review and "head-scratching" Thursday, NOAA's space-weather team calculated that most of the plasma blob should pass harmlessly over the top of the planet.
"It's more of a glancing blow," Pulkkinen said.
At their most intense, solar discharges, known as "coronal mass ejections," can disrupt satellites, radio communications and the power grid, and they can force airlines to reroute transcontinental flights that pass near the North Pole. Solar activity can also generate dancing auroras, the northern and southern lights.
Spit out by the sun Thursday morning, the huge blob of charged gas spotted by NASA satellites is speeding toward Earth at more than 2 million mph. The most damaging solar discharges, which are very rare, can zoom at speeds more than twice that fast.