Space hurricane

A space hurricane is a huge, funnel-like, spiral geomagnetic storm that occurs above the polar Ionosphere of Earth, during extremely quiet conditions.

[1][5] The space hurricane was characterized by a cyclone-like auroral spot with multiple spiral arms, due to precipitating electrons, strong circular plasma vorticity with zero horizontal flow at its center (the equivalent of the eye of an atmospheric hurricane), a negative-to-positive bipolar magnetic structure (showing a circular magnetic field perturbation), and a large and rapid deposition of energy and flux into the polar ionosphere (comparable to that during space weather superstorms).

The storm extended from the Ionosphere upward along geomagnetic field lines to cover a large fraction of the dayside polar magnetosphere, in the Northern Hemisphere.

[4] In the calm central region, encircled by the rotating plasma, there was a persistent auroral spot, associated with a strong, upward, field-aligned current caused by precipitating electrons.

[6] The phenomenon was discovered by a team of researchers from Shandong University in China, whom had observed the storm over the Arctic region on 20 August 2014, before identifying its nature in 2021.