What will happen when the solar storm strikes earth?
The Earth is currently being battered by a storm of charged particles from the Sun, which could disrupt power grids, satellite navigation and plane routes.
The storm was triggered by a pair of solar flares - the largest of their kind - earlier this week.
The effects will be most intense in polar regions, and aircraft may be advised to change their routings to avoid these areas.
Paul Cally, a professor of solar physics at Monash University in Australia, explains why.