While a severe G4 geomagnetic storm impressed sky watchers with Vivid auroras around the world. A much less visible, but historically significant, space weather event was also underway this week.
Solar radiation storms occur when a powerful magnetic flare on the sun, often involving a coronal mass ejection (CME), accelerates charged particles, mainly protons, to extreme speeds. These particles can reach a significant fraction of the speed of lightallowing them to traverse the approximately 93 million miles (150 million kilometers) between the sun and Land in tens of minutes or less, according to NOAA. When they arrive, the most energetic protons They can penetrate Earth’s magnetic defenses and travel along our planet’s magnetic field lines toward the polar regions, where they plunge into the upper atmosphere.
NOAA classifies solar radiation storms on a scale from S1 (minor) to S5 (extreme) based on GOES satellite measurements of incoming high-energy protons. The January 19 event reached S4 (severe) levels.
While it may seem dramatic, this type of storm poses no threat to people on Earth, thanks to Earth’s thick atmosphere and magnetic field, which absorb radiation before it reaches the surface.
Notably, this was not a “ground-level event,” in which the particles have enough energy to be detected on the Earth’s surface. As a space weather physicist Tamitha SkovThis storm had a relatively “soft” particle spectrum, of historic strength, but lacked the extreme energies necessary to reach the ground.
Well above the surface, the story is slightly different.
Severe radiation storms increase exposure risks for astronauts and for airline crews and passengers flying along polar routes, where the Earth’s magnetic shielding is weakest. Satellites are also vulnerable: Energetic particles can interfere with onboard electronics, disrupt sensors and overwhelm instruments. During this storm, some space weather forecasters reported temporary data losses, likely caused by intense proton fluxes. degrading spacecraft measurements.
Is a solar radiation storm the same as a geomagnetic storm?
No, they are different space weather phenomena with different effects. Solar radiation storms are driven by fast-moving particles from the sunwhile geomagnetic storms occur when disturbances in the solar wind interact with Earth’s magnetic field.
Geomagnetic storms occur most often when a CME’s magnetic field collides with Earth’s, but sometimes also when fast streams of solar wind flow outward from coronal holes. These interactions can trigger auroras and cause disruption to navigation, radio communications and power systems.
