In May 2024, Japan witnessed an extraordinary auroral display unlike anything scientists have observed before. The event, driven by a powerful geomagnetic storm, featured blue-dominant auroras and a salmon-pink glow, challenging long-established theories about their formation.
Researchers from Japan and Sweden investigated the phenomenon using public contributions and scientific data, unveiling new details about the spatial and structural characteristics of the blue auroras. Published in December 2024, the study has opened up a new chapter in understanding auroral processes.
Typically, auroras are produced by charged particles from the sun interacting with Earth’s magnetosphere. However, the blue auroras observed over Japan defied expectations by glowing at altitudes between 400 and 900 km, much higher than usual. This raised questions about what caused this peculiar phenomenon.
According to Professor Kazuo Shiokawa of Nagoya University, nitrogen molecular ions may have accelerated upward and were responsible for the formation of the blue-dominant aurora. However, there is still much scientists don’t understand about how these ions can persist in the upper atmosphere at high altitudes.
The study’s findings suggest that traditional models of aurora formation may not fully explain this new type of aurora. The blue auroras observed exhibited longitudinal structures, arranged along Earth’s magnetic field lines—a feature not previously identified in low-latitude auroras. This discovery further complicates current understanding and raises questions about unidentified atmospheric processes at higher altitudes.
The presence of nitrogen molecular ions remains shrouded in mystery. While their behavior is still unclear, the observation defies conventional scientific understanding. The study highlights the possibility of a previously unknown atmospheric mechanism that could accelerate these ions to extreme heights.
Source: https://dailygalaxy.com/2024/12/mysterious-blue-aurora-in-japan