Aurora Response to the Gannon Storm

The Gannon or May 10-11, 2024 superstorm created significant disturbances in the auroral activity patterns. The auroral oval expanded to ~40° Mlat during the storm. In addition to many known features, such as dawn-dusk asymmetry, detached ring current aurora, ENA aurora, undulation at equatorward edge, arcs etc., there are also a few new features: undulation on the poleward edge, arcs in the auroral oval cavity, penetration of plasma sheet energetic particles into the dayside polar cap, intense proton aurora, etc. These auroral features will be discussed in the context of the upstream solar wind, IMF and ionospheric conditions.