The northern lights lit up skies across much of the United States late Tuesday after a solar flare triggered a geomagnetic storm.
Forecasters had said the aurora borealis could be visible over a large portion of the country. In many states, green and purple hues were seen after sunset, with the lights most vibrant in the evening before the moonrise.
The Space Weather Prediction Center issued a geomagnetic storm watch before the event. Officials said a coronal mass ejection on Sunday traveled toward Earth at 4.4 million mph, aligning with the planet’s orbit and interacting with its magnetic field.
Severe geomagnetic storms can cause issues on the ground, the center said, including “possible widespread voltage control problems, and some protective systems [that] will mistakenly trip out key assets from the grid.” Spacecraft may also “experience surface charging and tracking problems; corrections may be needed for orientation problems.”
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Auroras occur when solar wind interacts with Earth’s magnetic field, funneling particles toward the planet’s poles. NASA says these particles can collide with atoms and molecules in the upper atmosphere, releasing energy as bursts of light. When visible from the ground, “we are watching a billion individual collisions, lighting up the magnetic field lines of Earth,” the agency said.
Will the aurora be visible Wednesday night?
The geomagnetic storm is forecast to continue Wednesday, with forecasters saying there is a high likelihood of the northern lights being visible over the Upper Midwest and New England between 8 and 10 p.m. local time, fading after midnight.
While the western United States is not ruled out, forecasters say eastern states have a better chance of seeing the aurora tonight.
