The sun is furiously demanding our attention again, flexing near the peak of its power with four eruptions at the same time.
Video footage from NASA‘s Solar Dynamics Observatory shows that, around 11:30 p.m. Eastern Time on Monday evening, four solar flares erupted at once across the visible surface of the sun.
NASA Solar Dynamics Observatory
Solar flares can send solar material screaming toward Earth, causing geomagnetic storms in our planet’s atmosphere.
That can lead to GPS disruptions and radio blackouts, or bring the beautiful northern lights further south.
Indeed, a radio blackout occurred shortly after the flares, according to the Space Weather Prediction Center at the National Oceanic and Atmospheric Administration, though it was not clear from the agency’s report whether this was linked.
“These things are very difficult to forecast, but I wouldn’t expect too much geomagnetic activity from these particular events,” Mathew Owens, a professor of space physics at the University of Reading, told Business Insider in an email. “We might get something of a glancing blow from one of them in a day or two.”
The SWPC did not immediately respond to a request for comment. Though these eruptions were facing Earth, as of Wednesday morning the center wasn’t forecasting any geomagnetic storms for the next three days.
A ‘super-sympathetic’ solar flare event
The simultaneous and powerful flares probably resulted from one underlying trigger, in a phenomenon known as a “sympathetic solar flare.”
Magnetic loops at the outermost part of the sun, called the corona, can connect sunspots or filaments. When one explodes, it creates an instability in these magnetic forces that can set off other eruptions, Spaceweather.com explains.
It’s a “domino effect,” Owens said, “where one region becomes unstable and sets off activity in a bunch of other locations, often at great distance.”
Sympathetic solar flares usually involve only two concurrent explosions, making this flare a “super-sympathetic” one.
“This is indeed a fascinating event. It’s quite rare to find sympathetic flaring at four locations,” Daniel Verscharen, a physicist and associate professor of space plasma at University College London, told BI in an email.
Scientists still don’t understand the exact mechanism behind sympathetic flares.
“A likely explanation is that one flare erupts and triggers a disturbance that travels through the solar corona,” Verscharen said. “This disturbance could be a shock wave that travels from the first flare around the sun. When this disturbance encounters another active region, it may trigger that region to become unstable and erupt as well.”
The sun is peaking
Though this event appears striking, it’s exactly the right time for rare events on the sun. Our star is near solar maximum, the peak of its 11-year cycle, where it becomes hyperactive.
That’s why the last year has brought a barrage of solar flares, eruptions, and coronal holes that send winds of plasma and magnetically charged particles washing over Earth.
Scientists aren’t yet sure whether the sun has already hit solar maximum, but if it hasn’t, then maximum is likely to occur within the next year.
From then on, solar activity will decline for years, meaning less radio and GPS disruption on Earth, as well as far fewer chances to see the northern lights.
