Stunning Aurora Substorm Captured by Stargazers
Many planets, including Earth, are surrounded by a magnetosphere—an immense magnetic shield created by the motion of molten metal within their cores. This shield stretches into space and protects the planet by deflecting harmful charged particles from the solar wind.
How Geomagnetic Storms Form
When regions of Earth’s magnetosphere become overloaded with absorbed energy, geomagnetic storms can form, much like thunderclouds before rainfall. During such storms, energy travels along magnetic field lines and cascades into the atmosphere, triggering brilliant auroral displays even far from the poles.
"The particle precipitation during geomagnetic storms injects millions of amps into the atmosphere, creating spectacular auroral displays far from the poles."
Solar Activity and Coronal Mass Ejections
At times, the Sun releases immense bursts of plasma and magnetic fields known as coronal mass ejections (CMEs). These eruptions hurl clouds of solar material into space, and when they reach Earth, they can amplify auroras and generate striking lights in the night sky.
Colors of the Northern Lights
Green auroras are the most common, created when electrons excite oxygen atoms at altitudes of 100–200 km.
Blue auroras appear when nitrogen gas is energized at similar heights.
Reddish-purple or pink glows arise when nitrogen is excited below 100 km.
Author’s Summary
Energetic solar activity and Earth’s magnetic field together produce the mesmerizing light curtains of the aurora, revealing our planet’s delicate balance with cosmic forces.