News: Sky-watchers worldwide witnessed breathtaking auroras as a severe G4 geomagnetic storm pushed the dazzling lights far beyond their typical polar regions.
About G4 Geomagnetic Storm
- Geomagnetic Storm: A geomagnetic storm is a severe disturbance of Earth’s magnetosphere.
- How it is caused: Energy produced by nuclear fusion in the Sun is released as sunlight, radiation, and charged particles.
- These charged particles constantly flow away from the Sun as the solar wind.
- Sometimes, the Sun releases large clouds of plasma called coronal mass ejections.
- When these charged particles or plasma reach Earth, they collide with Earth’s magnetic field.
- This disturbs the magnetic field and causes a geomagnetic storm.
- Favourable conditions:
- Geomagnetic storms occur when the solar wind blows toward Earth at a very high speed for several hours.
- A southward directed solar wind magnetic field (opposite the direction of Earth’s field) at the dayside of the magnetosphere.
- Classification: Geomagnetic storms are classified on the G-scale, ranging from G1 (minor) to G5 (extreme).
- A G4 storm falls under the severe category, indicating intense geomagnetic activity.
- Impacts
- G4 geomagnetic storms can cause serious disturbances in satellite operations.
- Power systems may experience voltage instability and increased risk of damage.
- Radio communications, especially on the sunlit side of Earth, can be disrupted.
- GPS and navigation systems may show reduced accuracy during the storm.
- Auroral Effects: During strong geomagnetic storms, the auroral oval expands, allowing auroras to be visible at much lower latitudes than usual.
