On Sunday, the sun’s corona, or gas atmosphere, discharged a massive outburst of particles, which sped towards Earth at speeds up to 2,000 kilometres per second. Disturbances recorded in the magnetic field around 5pm on Tuesday were the first signs that the magnetic cloud was reaching Earth.
The Finnish Meteorological Institute says such a strong sun storm could even damage satellites orbiting the Earth.
Delta Air Lines said it was diverting some flights on polar routes between Detroit and Asia to avoid disruptions to aircraft communications by the strong solar radiation storm.