Severe solar storm alert: NASA tracks CME as NOAA upgrades G4 geomagnetic storm
A severe G4 geomagnetic storm struck early Tuesday after a coronal mass ejection from a Jan. 18 X-class solar flare, NOAA said. A rare S4 solar radiation storm is also underway, raising risks for polar flights, satellites, and astronauts. The geomagnetic storm first reached G4 on Monday afternoon and peaked again overnight. NASA reported gaps in SOHO data but confirmed the event with other instruments.
