Overview
- Researchers report in Geophysical Research Letters that a blue aurora over Kiruna, Sweden, reached maximum intensity near 200 kilometers, far above the ~125 kilometers expected by models.
- Using the HySCAI hyperspectral camera, the team separated faint nitrogen emission from scattered sunlight to retrieve the aurora’s altitude profile for the first time.
- The physical cause of the high ionized-nitrogen density at that altitude remains unclear, with candidates including upward transport of N+ or charge exchange from abundant oxygen ions.
- The Space Weather Prediction Center measured a G3 geomagnetic storm that arrived on November 4, raising near-term viewing chances, especially across northern Germany and potentially into Berlin, Brandenburg, Saxony-Anhalt, Saxony and North Rhine-Westphalia through Friday.
- Observers are advised to seek dark locations and use long‑exposure photography, and recent activity comes during a solar‑cycle maximum that has already produced notable displays, including a G5 event in May 2024.