A geomagnetic storm hit our planet over the weekend, surprising scientists, as it did not appear to have originated from a solar flare.
The storm occurred amid a rare alignment of five planets, giving photographers a chance to imagine them against a bright aurora.
Astronomers now believe the storm was the result of a much rarer phenomenon than a solar flare, something called a co-rotating interaction region (CIR) caused by two intersecting solar wind currents.
CIRs are created when solar wind currents at different speeds interact, bringing with them a large shock and an accumulation of plasma at an extraordinary speed -700 km per second in this case- and without the telltale signal of a sunspot.
Without a sunspot that signaled an ejection of coronal mass, the scientists had no sign that a geomagnetic storm was on its way.
When it hit Earth, the storm managed to “open a crack in our planet’s magnetosphere,” according to the Space Weather news site.
The solar storm followed a week after a huge sunspot, more than twice the size of our planet, pointed at Earth.
Although it subsequently receded and the risk of a dangerous CME faded, scientists do not know if it was connected to the CIR.
But even if we could have predicted the storm, the planet has limited defenses against the most powerful forms of space climate, and our growing dependence on electronics makes us vulnerable to its effects.
The Carrington event is believed to be the largest solar storm ever recorded to hit Earth in 1859.
It left an aurora visible in the sky, even at latitudes much closer to the equator, and was described in contemporary reports as even brighter than full moonlight.
It caused the failure of telegraph systems throughout Europe and North America, and a similar storm today could cause trillions of dollars in damage worldwide.
Researchers believe that magnetic radiation from giant solar storms caused the sudden and almost instantaneous detonation of dozens of sea mines in Vietnam in the 1970s.
Earlier this year, SpaceX confirmed that a geomagnetic storm destroyed most of the Starlink satellites it had attempted to launch into orbit during a launch.
Solar activity has been observed to rise and fall naturally every 11 years, though not like a clock, and astronomers believe we are now entering a period of increasing solar activity that could reach its peak. maximum in 2025.
A new family of sunspots, discovered on the surface of our star in 2020, triggered the largest solar flare scientists have seen since 2017.