Even though the solar wind was unusually dense during the May 2024 superstorm, ions from the solar wind contributed very little to the ring current, marking the first time both were observed simultaneously during a storm of this magnitude.

In May 2024, auroras spread into skies far beyond their usual range, appearing at unusually low latitudes around the world. Far above those displays, inside Earth’s magnetosphere, measurements were capturing something never before seen during a geomagnetic storm of this magnitude.

The storm began when a large sunspot unleashed a rapid sequence of powerful solar eruptions. Multiple clouds of magnetized plasma merged on their way through space before striking Earth’s magnetosphere, the region dominated by our planet’s magnetic field. The resulting disturbance was the strongest ever measured directly in Earth’s ring current region, a belt of charged particles surrounding the planet.