What is Space Weather?
The term space weather refers to events beyond the Earth's atmosphere that impact upon our technology and the near-Earth space environment. The primary source of space weather is the sun, with the greatest disturbances usually caused by solar flares and subsequent geomagnetic storms.
Solar flare eruptions are sometimes associated with:
- increased X-ray and radio emissions that reach Earth within eight minutes (sometimes up into the ultra-high frequency (UHF) band);
- an increase in the flux of energetic protons typically reaching Earth in 30 minutes to six hours (referred to as solar energetic protons or solar energetic particles or SEPs) and
- an increase in the mass and velocity of solar wind particles and magnetic field strength reaching Earth typically within half a day to three days (collectively termed a coronal mass ejection or CME).
On reaching Earth, a CME may cause geomagnetic and ionospheric storms. All these phenomena can have an impact on technologies in the near-Earth space environment.
Extreme space weather can disrupt, damage or cause the loss of critical infrastructure.
Subscribe to the Bureau's Severe Space Weather Warning service.