On certain nights in Japan, people may notice a faint red glow spreading low across the horizon. The dim crimson haze can be easy to overlook, but it is created by powerful activity taking place far above Earth. Streams of charged particles from the Sun travel toward our planet and interact with Earth's magnetic field. When these particles collide with oxygen atoms high in the atmosphere, the atoms release energy as soft red light, producing rare auroras visible from the ground.
A new study published in the Journal of Space Weather and Space Climate reports that researchers from Hokkaido University and the Okinawa Institute of Science and Technology observed unusual red auroras above Japan at far greater heights than expected. The glowing displays extended roughly 500 to 800 kilometers above Earth's surface.
Rare Red Auroras Reach Extreme Heights
Auroras are most commonly seen near the polar regions, where charged solar particles interact with Earth's atmosphere to create shimmering lights in the sky. In Japan and other areas farther south, auroras are much less common and are usually linked to powerful geomagnetic storms. These events typically occur at altitudes of around 200 to 400 kilometers.
