Abstract:

The aurora is one of the most captivating natural phenomena in the night sky. Typically occurring in Earth’s polar regions, auroral activity is concentrated in an oval-shaped region known as the auroral oval. Within this region, a variety of visually stunning and physically complex structures emerge. Just equatorward of this lies the subauroral region—an area that, while scientifically intriguing, has traditionally been less visually dramatic.

That changed with the discovery of a remarkable new optical phenomenon: STEVE (Strong Thermal Emission Velocity Enhancement). Unlike traditional aurora, STEVE originates in the subauroral ionosphere and presents as an extremely narrow, luminous ribbon of purplish-white light stretching across the sky. First reported by citizen scientists, STEVE has since sparked great interest within the public and the scientific community.

Combining data from ground-based and satellite instruments with citizen science observations has opened up a unique avenue for exploring this phenomenon. In this seminar, we will review our current understanding of STEVE, highlight recent findings, and discuss the many open questions that remain. These questions present exciting opportunities for future research and interdisciplinary collaboration.