A powerful X2.8 solar flare erupted from the sun on Thursday afternoon, the strongest such eruption in over six years. The flare caused radio blackouts in South America and may also spark auroras as far south as New York and Idaho in the next couple of days, forecasters said.
Spaceweather.com called it the most powerful sunstorm since September 2017, while the Space Weather Prediction Center termed it "one of the largest solar radio events ever recorded."
Solar flares are intense bursts of radiation released by magnetic activity on the sun. They can impact radio signals, power grids and navigation systems and endanger astronauts. The X-classification denotes the most extreme flares, with the number providing more specifics on its potency.
This event also released a coronal mass ejection - a massive solar plasma and magnetic field cloud - that may reach Earth. Such clouds can provoke geomagnetic storms when they interact with our planet's field, spawning colorful northern lights displays.
The Space Weather Prediction Center has issued a G2 or "moderate" geomagnetic storm watch for December 17-18, meaning auroras may dip as far south as New York and Idaho.